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) {
704 ret
= update_kernel_poll(&events
);
708 update_poll_flag
= 0;
711 nb_fd
= LTTNG_POLL_GETNB(&events
);
713 DBG("Thread kernel polling on %d fds", nb_fd
);
715 /* Zeroed the poll events */
716 lttng_poll_reset(&events
);
718 /* Poll infinite value of time */
719 ret
= lttng_poll_wait(&events
, -1);
722 } else if (ret
== 0) {
723 /* Should not happen since timeout is infinite */
724 ERR("Return value of poll is 0 with an infinite timeout.\n"
725 "This should not have happened! Continuing...");
729 for (i
= 0; i
< nb_fd
; i
++) {
730 /* Fetch once the poll data */
731 revents
= LTTNG_POLL_GETEV(&events
, i
);
732 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
734 /* Thread quit pipe has been closed. Killing thread. */
735 ret
= check_thread_quit_pipe(pollfd
, revents
);
740 /* Check for data on kernel pipe */
741 if (pollfd
== kernel_poll_pipe
[0] && (revents
& LPOLLIN
)) {
742 ret
= read(kernel_poll_pipe
[0], &tmp
, 1);
743 update_poll_flag
= 1;
747 * New CPU detected by the kernel. Adding kernel stream to
748 * kernel session and updating the kernel consumer
750 if (revents
& LPOLLIN
) {
751 ret
= update_kernel_stream(pollfd
);
757 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
758 * and unregister kernel stream at this point.
766 DBG("Kernel thread dying");
767 close(kernel_poll_pipe
[0]);
768 close(kernel_poll_pipe
[1]);
770 lttng_poll_clean(&events
);
776 * This thread manage the kconsumerd error sent back to the session daemon.
778 static void *thread_manage_kconsumerd(void *data
)
780 int sock
= 0, i
, ret
, pollfd
;
781 uint32_t revents
, nb_fd
;
782 enum lttcomm_return_code code
;
783 struct lttng_poll_event events
;
785 DBG("[thread] Manage kconsumerd started");
787 ret
= lttcomm_listen_unix_sock(kconsumerd_err_sock
);
793 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
794 * Nothing more will be added to this poll set.
796 ret
= create_thread_poll_set(&events
, 2);
801 ret
= lttng_poll_add(&events
, kconsumerd_err_sock
, LPOLLIN
| LPOLLRDHUP
);
806 nb_fd
= LTTNG_POLL_GETNB(&events
);
808 /* Inifinite blocking call, waiting for transmission */
809 ret
= lttng_poll_wait(&events
, -1);
814 for (i
= 0; i
< nb_fd
; i
++) {
815 /* Fetch once the poll data */
816 revents
= LTTNG_POLL_GETEV(&events
, i
);
817 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
819 /* Thread quit pipe has been closed. Killing thread. */
820 ret
= check_thread_quit_pipe(pollfd
, revents
);
825 /* Event on the registration socket */
826 if (pollfd
== kconsumerd_err_sock
) {
827 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
828 ERR("Kconsumerd err socket poll error");
834 sock
= lttcomm_accept_unix_sock(kconsumerd_err_sock
);
839 /* Getting status code from kconsumerd */
840 ret
= lttcomm_recv_unix_sock(sock
, &code
,
841 sizeof(enum lttcomm_return_code
));
846 if (code
== KCONSUMERD_COMMAND_SOCK_READY
) {
847 kconsumerd_cmd_sock
=
848 lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path
);
849 if (kconsumerd_cmd_sock
< 0) {
850 sem_post(&kconsumerd_sem
);
851 perror("kconsumerd connect");
854 /* Signal condition to tell that the kconsumerd is ready */
855 sem_post(&kconsumerd_sem
);
856 DBG("Kconsumerd command socket ready");
858 DBG("Kconsumerd error when waiting for SOCK_READY : %s",
859 lttcomm_get_readable_code(-code
));
863 /* Remove the kconsumerd error sock since we've established a connexion */
864 ret
= lttng_poll_del(&events
, kconsumerd_err_sock
);
869 ret
= lttng_poll_add(&events
, sock
, LPOLLIN
| LPOLLRDHUP
);
874 /* Update number of fd */
875 nb_fd
= LTTNG_POLL_GETNB(&events
);
877 /* Inifinite blocking call, waiting for transmission */
878 ret
= lttng_poll_wait(&events
, -1);
883 for (i
= 0; i
< nb_fd
; i
++) {
884 /* Fetch once the poll data */
885 revents
= LTTNG_POLL_GETEV(&events
, i
);
886 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
888 /* Thread quit pipe has been closed. Killing thread. */
889 ret
= check_thread_quit_pipe(pollfd
, revents
);
894 /* Event on the kconsumerd socket */
895 if (pollfd
== sock
) {
896 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
897 ERR("Kconsumerd err socket second poll error");
903 /* Wait for any kconsumerd error */
904 ret
= lttcomm_recv_unix_sock(sock
, &code
,
905 sizeof(enum lttcomm_return_code
));
907 ERR("Kconsumerd closed the command socket");
911 ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code
));
914 DBG("Kconsumerd thread dying");
915 close(kconsumerd_err_sock
);
916 close(kconsumerd_cmd_sock
);
919 unlink(kconsumerd_err_unix_sock_path
);
920 unlink(kconsumerd_cmd_unix_sock_path
);
923 lttng_poll_clean(&events
);
929 * This thread manage application communication.
931 static void *thread_manage_apps(void *data
)
934 uint32_t revents
, nb_fd
;
935 struct ust_command ust_cmd
;
936 struct lttng_poll_event events
;
938 DBG("[thread] Manage application started");
940 ret
= create_thread_poll_set(&events
, 2);
945 ret
= lttng_poll_add(&events
, apps_cmd_pipe
[0], LPOLLIN
| LPOLLRDHUP
);
951 /* Zeroed the events structure */
952 lttng_poll_reset(&events
);
954 nb_fd
= LTTNG_POLL_GETNB(&events
);
956 DBG("Apps thread polling on %d fds", nb_fd
);
958 /* Inifinite blocking call, waiting for transmission */
959 ret
= lttng_poll_wait(&events
, -1);
964 for (i
= 0; i
< nb_fd
; i
++) {
965 /* Fetch once the poll data */
966 revents
= LTTNG_POLL_GETEV(&events
, i
);
967 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
969 /* Thread quit pipe has been closed. Killing thread. */
970 ret
= check_thread_quit_pipe(pollfd
, revents
);
975 /* Inspect the apps cmd pipe */
976 if (pollfd
== apps_cmd_pipe
[0]) {
977 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
978 ERR("Apps command pipe error");
980 } else if (revents
& LPOLLIN
) {
982 ret
= read(apps_cmd_pipe
[0], &ust_cmd
, sizeof(ust_cmd
));
983 if (ret
< 0 || ret
< sizeof(ust_cmd
)) {
984 perror("read apps cmd pipe");
988 /* Register applicaton to the session daemon */
989 ret
= ust_app_register(&ust_cmd
.reg_msg
,
992 /* Only critical ENOMEM error can be returned here */
996 ret
= ustctl_register_done(ust_cmd
.sock
);
999 * If the registration is not possible, we simply
1000 * unregister the apps and continue
1002 ust_app_unregister(ust_cmd
.sock
);
1005 * We just need here to monitor the close of the UST
1006 * socket and poll set monitor those by default.
1008 ret
= lttng_poll_add(&events
, ust_cmd
.sock
, 0);
1013 DBG("Apps with sock %d added to poll set",
1020 * At this point, we know that a registered application made
1021 * the event at poll_wait.
1023 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1024 /* Removing from the poll set */
1025 ret
= lttng_poll_del(&events
, pollfd
);
1031 ust_app_unregister(pollfd
);
1039 DBG("Application communication apps dying");
1040 close(apps_cmd_pipe
[0]);
1041 close(apps_cmd_pipe
[1]);
1043 lttng_poll_clean(&events
);
1049 * Dispatch request from the registration threads to the application
1050 * communication thread.
1052 static void *thread_dispatch_ust_registration(void *data
)
1055 struct cds_wfq_node
*node
;
1056 struct ust_command
*ust_cmd
= NULL
;
1058 DBG("[thread] Dispatch UST command started");
1060 while (!dispatch_thread_exit
) {
1061 /* Atomically prepare the queue futex */
1062 futex_nto1_prepare(&ust_cmd_queue
.futex
);
1065 /* Dequeue command for registration */
1066 node
= cds_wfq_dequeue_blocking(&ust_cmd_queue
.queue
);
1068 DBG("Waked up but nothing in the UST command queue");
1069 /* Continue thread execution */
1073 ust_cmd
= caa_container_of(node
, struct ust_command
, node
);
1075 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1076 " gid:%d sock:%d name:%s (version %d.%d)",
1077 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1078 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1079 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1080 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1082 * Inform apps thread of the new application registration. This
1083 * call is blocking so we can be assured that the data will be read
1084 * at some point in time or wait to the end of the world :)
1086 ret
= write(apps_cmd_pipe
[1], ust_cmd
,
1087 sizeof(struct ust_command
));
1089 perror("write apps cmd pipe");
1090 if (errno
== EBADF
) {
1092 * We can't inform the application thread to process
1093 * registration. We will exit or else application
1094 * registration will not occur and tracing will never
1101 } while (node
!= NULL
);
1103 /* Futex wait on queue. Blocking call on futex() */
1104 futex_nto1_wait(&ust_cmd_queue
.futex
);
1108 DBG("Dispatch thread dying");
1113 * This thread manage application registration.
1115 static void *thread_registration_apps(void *data
)
1117 int sock
= 0, i
, ret
, pollfd
;
1118 uint32_t revents
, nb_fd
;
1119 struct lttng_poll_event events
;
1121 * Get allocated in this thread, enqueued to a global queue, dequeued and
1122 * freed in the manage apps thread.
1124 struct ust_command
*ust_cmd
= NULL
;
1126 DBG("[thread] Manage application registration started");
1128 ret
= lttcomm_listen_unix_sock(apps_sock
);
1134 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1135 * more will be added to this poll set.
1137 ret
= create_thread_poll_set(&events
, 2);
1142 /* Add the application registration socket */
1143 ret
= lttng_poll_add(&events
, apps_sock
, LPOLLIN
| LPOLLRDHUP
);
1148 /* Notify all applications to register */
1149 ret
= notify_ust_apps(1);
1151 ERR("Failed to notify applications or create the wait shared memory.\n"
1152 "Execution continues but there might be problem for already\n"
1153 "running applications that wishes to register.");
1157 DBG("Accepting application registration");
1159 nb_fd
= LTTNG_POLL_GETNB(&events
);
1161 /* Inifinite blocking call, waiting for transmission */
1162 ret
= lttng_poll_wait(&events
, -1);
1167 for (i
= 0; i
< nb_fd
; i
++) {
1168 /* Fetch once the poll data */
1169 revents
= LTTNG_POLL_GETEV(&events
, i
);
1170 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
1172 /* Thread quit pipe has been closed. Killing thread. */
1173 ret
= check_thread_quit_pipe(pollfd
, revents
);
1178 /* Event on the registration socket */
1179 if (pollfd
== apps_sock
) {
1180 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1181 ERR("Register apps socket poll error");
1183 } else if (revents
& LPOLLIN
) {
1184 sock
= lttcomm_accept_unix_sock(apps_sock
);
1189 /* Create UST registration command for enqueuing */
1190 ust_cmd
= malloc(sizeof(struct ust_command
));
1191 if (ust_cmd
== NULL
) {
1192 perror("ust command malloc");
1197 * Using message-based transmissions to ensure we don't
1198 * have to deal with partially received messages.
1200 ret
= lttcomm_recv_unix_sock(sock
, &ust_cmd
->reg_msg
,
1201 sizeof(struct ust_register_msg
));
1202 if (ret
< 0 || ret
< sizeof(struct ust_register_msg
)) {
1204 perror("lttcomm_recv_unix_sock register apps");
1206 ERR("Wrong size received on apps register");
1213 ust_cmd
->sock
= sock
;
1215 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1216 " gid:%d sock:%d name:%s (version %d.%d)",
1217 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1218 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1219 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1220 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1223 * Lock free enqueue the registration request. The red pill
1224 * has been taken! This apps will be part of the *system*.
1226 cds_wfq_enqueue(&ust_cmd_queue
.queue
, &ust_cmd
->node
);
1229 * Wake the registration queue futex. Implicit memory
1230 * barrier with the exchange in cds_wfq_enqueue.
1232 futex_nto1_wake(&ust_cmd_queue
.futex
);
1239 DBG("UST Registration thread dying");
1241 /* Notify that the registration thread is gone */
1246 unlink(apps_unix_sock_path
);
1248 lttng_poll_clean(&events
);
1254 * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
1255 * exec or it will fails.
1257 static int spawn_kconsumerd_thread(void)
1261 /* Setup semaphore */
1262 sem_init(&kconsumerd_sem
, 0, 0);
1264 ret
= pthread_create(&kconsumerd_thread
, NULL
,
1265 thread_manage_kconsumerd
, (void *) NULL
);
1267 perror("pthread_create kconsumerd");
1271 /* Wait for the kconsumerd thread to be ready */
1272 sem_wait(&kconsumerd_sem
);
1274 if (kconsumerd_pid
== 0) {
1275 ERR("Kconsumerd did not start");
1282 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1287 * Join kernel consumer thread
1289 static int join_kconsumerd_thread(void)
1294 if (kconsumerd_pid
!= 0) {
1295 ret
= kill(kconsumerd_pid
, SIGTERM
);
1297 ERR("Error killing kconsumerd");
1300 return pthread_join(kconsumerd_thread
, &status
);
1307 * Fork and exec a kernel consumer daemon (kconsumerd).
1309 * Return pid if successful else -1.
1311 static pid_t
spawn_kconsumerd(void)
1315 const char *verbosity
;
1317 DBG("Spawning kconsumerd");
1324 if (opt_verbose
> 1 || opt_verbose_kconsumerd
) {
1325 verbosity
= "--verbose";
1327 verbosity
= "--quiet";
1329 execl(INSTALL_BIN_PATH
"/ltt-kconsumerd",
1330 "ltt-kconsumerd", verbosity
, NULL
);
1332 perror("kernel start consumer exec");
1335 } else if (pid
> 0) {
1339 perror("kernel start consumer fork");
1349 * Spawn the kconsumerd daemon and session daemon thread.
1351 static int start_kconsumerd(void)
1355 pthread_mutex_lock(&kconsumerd_pid_mutex
);
1356 if (kconsumerd_pid
!= 0) {
1357 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1361 ret
= spawn_kconsumerd();
1363 ERR("Spawning kconsumerd failed");
1364 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1365 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1369 /* Setting up the global kconsumerd_pid */
1370 kconsumerd_pid
= ret
;
1371 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1373 DBG("Kconsumerd pid %d", ret
);
1375 DBG("Spawning kconsumerd thread");
1376 ret
= spawn_kconsumerd_thread();
1378 ERR("Fatal error spawning kconsumerd thread");
1390 * modprobe_kernel_modules
1392 static int modprobe_kernel_modules(void)
1397 for (i
= 0; i
< ARRAY_SIZE(kernel_modules_list
); i
++) {
1398 ret
= snprintf(modprobe
, sizeof(modprobe
),
1399 "/sbin/modprobe %s%s",
1400 kernel_modules_list
[i
].required
? "" : "--quiet ",
1401 kernel_modules_list
[i
].name
);
1403 perror("snprintf modprobe");
1406 modprobe
[sizeof(modprobe
) - 1] = '\0';
1407 ret
= system(modprobe
);
1409 ERR("Unable to launch modprobe for module %s",
1410 kernel_modules_list
[i
].name
);
1411 } else if (kernel_modules_list
[i
].required
1412 && WEXITSTATUS(ret
) != 0) {
1413 ERR("Unable to load module %s",
1414 kernel_modules_list
[i
].name
);
1416 DBG("Modprobe successfully %s",
1417 kernel_modules_list
[i
].name
);
1428 static int mount_debugfs(char *path
)
1431 char *type
= "debugfs";
1433 ret
= mkdir_recursive(path
, S_IRWXU
| S_IRWXG
, geteuid(), getegid());
1438 ret
= mount(type
, path
, type
, 0, NULL
);
1440 perror("mount debugfs");
1444 DBG("Mounted debugfs successfully at %s", path
);
1451 * Setup necessary data for kernel tracer action.
1453 static void init_kernel_tracer(void)
1456 char *proc_mounts
= "/proc/mounts";
1458 char *debugfs_path
= NULL
, *lttng_path
= NULL
;
1461 /* Detect debugfs */
1462 fp
= fopen(proc_mounts
, "r");
1464 ERR("Unable to probe %s", proc_mounts
);
1468 while (fgets(line
, sizeof(line
), fp
) != NULL
) {
1469 if (strstr(line
, "debugfs") != NULL
) {
1470 /* Remove first string */
1472 /* Dup string here so we can reuse line later on */
1473 debugfs_path
= strdup(strtok(NULL
, " "));
1474 DBG("Got debugfs path : %s", debugfs_path
);
1481 /* Mount debugfs if needded */
1482 if (debugfs_path
== NULL
) {
1483 ret
= asprintf(&debugfs_path
, "/mnt/debugfs");
1485 perror("asprintf debugfs path");
1488 ret
= mount_debugfs(debugfs_path
);
1494 /* Modprobe lttng kernel modules */
1495 ret
= modprobe_kernel_modules();
1500 /* Setup lttng kernel path */
1501 ret
= asprintf(<tng_path
, "%s/lttng", debugfs_path
);
1503 perror("asprintf lttng path");
1507 /* Open debugfs lttng */
1508 kernel_tracer_fd
= open(lttng_path
, O_RDWR
);
1509 if (kernel_tracer_fd
< 0) {
1510 DBG("Failed to open %s", lttng_path
);
1516 DBG("Kernel tracer fd %d", kernel_tracer_fd
);
1526 WARN("No kernel tracer available");
1527 kernel_tracer_fd
= 0;
1532 * Init tracing by creating trace directory and sending fds kernel consumer.
1534 static int init_kernel_tracing(struct ltt_kernel_session
*session
)
1538 if (session
->kconsumer_fds_sent
== 0) {
1540 * Assign default kernel consumer socket if no consumer assigned to the
1541 * kernel session. At this point, it's NOT suppose to be 0 but this is
1542 * an extra security check.
1544 if (session
->consumer_fd
== 0) {
1545 session
->consumer_fd
= kconsumerd_cmd_sock
;
1548 ret
= send_kconsumerd_fds(session
);
1550 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1554 session
->kconsumer_fds_sent
= 1;
1562 * Create an UST session and add it to the session ust list.
1564 static int create_ust_session(struct ltt_session
*session
,
1565 struct lttng_domain
*domain
)
1568 struct ltt_ust_session
*lus
;
1569 struct ust_app
*app
;
1571 switch (domain
->type
) {
1572 case LTTNG_DOMAIN_UST_PID
:
1573 app
= ust_app_get_by_pid(domain
->attr
.pid
);
1575 ret
= LTTCOMM_APP_NOT_FOUND
;
1583 DBG("Creating UST session");
1585 lus
= trace_ust_create_session(session
->path
, domain
->attr
.pid
, domain
);
1587 ret
= LTTCOMM_UST_SESS_FAIL
;
1591 ret
= mkdir_recursive(lus
->path
, S_IRWXU
| S_IRWXG
,
1592 geteuid(), allowed_group());
1594 if (ret
!= -EEXIST
) {
1595 ERR("Trace directory creation error");
1596 ret
= LTTCOMM_UST_SESS_FAIL
;
1601 /* Create session on the UST tracer */
1602 ret
= ustctl_create_session(app
->sock
, lus
);
1604 ret
= LTTCOMM_UST_SESS_FAIL
;
1608 cds_list_add(&lus
->list
, &session
->ust_session_list
.head
);
1609 session
->ust_session_list
.count
++;
1619 * Create a kernel tracer session then create the default channel.
1621 static int create_kernel_session(struct ltt_session
*session
)
1625 DBG("Creating kernel session");
1627 ret
= kernel_create_session(session
, kernel_tracer_fd
);
1629 ret
= LTTCOMM_KERN_SESS_FAIL
;
1633 /* Set kernel consumer socket fd */
1634 if (kconsumerd_cmd_sock
) {
1635 session
->kernel_session
->consumer_fd
= kconsumerd_cmd_sock
;
1638 ret
= mkdir_recursive(session
->kernel_session
->trace_path
,
1639 S_IRWXU
| S_IRWXG
, geteuid(), allowed_group());
1641 if (ret
!= -EEXIST
) {
1642 ERR("Trace directory creation error");
1652 * Using the session list, filled a lttng_session array to send back to the
1653 * client for session listing.
1655 * The session list lock MUST be acquired before calling this function. Use
1656 * session_lock_list() and session_unlock_list().
1658 static void list_lttng_sessions(struct lttng_session
*sessions
)
1661 struct ltt_session
*session
;
1663 DBG("Getting all available session");
1665 * Iterate over session list and append data after the control struct in
1668 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
1669 strncpy(sessions
[i
].path
, session
->path
, PATH_MAX
);
1670 sessions
[i
].path
[PATH_MAX
- 1] = '\0';
1671 strncpy(sessions
[i
].name
, session
->name
, NAME_MAX
);
1672 sessions
[i
].name
[NAME_MAX
- 1] = '\0';
1678 * Fill lttng_channel array of all channels.
1680 static void list_lttng_channels(struct ltt_session
*session
,
1681 struct lttng_channel
*channels
)
1684 struct ltt_kernel_channel
*kchan
;
1686 DBG("Listing channels for session %s", session
->name
);
1688 /* Kernel channels */
1689 if (session
->kernel_session
!= NULL
) {
1690 cds_list_for_each_entry(kchan
,
1691 &session
->kernel_session
->channel_list
.head
, list
) {
1692 /* Copy lttng_channel struct to array */
1693 memcpy(&channels
[i
], kchan
->channel
, sizeof(struct lttng_channel
));
1694 channels
[i
].enabled
= kchan
->enabled
;
1699 /* TODO: Missing UST listing */
1703 * Fill lttng_event array of all events in the channel.
1705 static void list_lttng_events(struct ltt_kernel_channel
*kchan
,
1706 struct lttng_event
*events
)
1709 * TODO: This is ONLY kernel. Need UST support.
1712 struct ltt_kernel_event
*event
;
1714 DBG("Listing events for channel %s", kchan
->channel
->name
);
1716 /* Kernel channels */
1717 cds_list_for_each_entry(event
, &kchan
->events_list
.head
, list
) {
1718 strncpy(events
[i
].name
, event
->event
->name
, LTTNG_SYMBOL_NAME_LEN
);
1719 events
[i
].name
[LTTNG_SYMBOL_NAME_LEN
- 1] = '\0';
1720 events
[i
].enabled
= event
->enabled
;
1721 switch (event
->event
->instrumentation
) {
1722 case LTTNG_KERNEL_TRACEPOINT
:
1723 events
[i
].type
= LTTNG_EVENT_TRACEPOINT
;
1725 case LTTNG_KERNEL_KPROBE
:
1726 case LTTNG_KERNEL_KRETPROBE
:
1727 events
[i
].type
= LTTNG_EVENT_PROBE
;
1728 memcpy(&events
[i
].attr
.probe
, &event
->event
->u
.kprobe
,
1729 sizeof(struct lttng_kernel_kprobe
));
1731 case LTTNG_KERNEL_FUNCTION
:
1732 events
[i
].type
= LTTNG_EVENT_FUNCTION
;
1733 memcpy(&events
[i
].attr
.ftrace
, &event
->event
->u
.ftrace
,
1734 sizeof(struct lttng_kernel_function
));
1736 case LTTNG_KERNEL_NOOP
:
1737 events
[i
].type
= LTTNG_EVENT_NOOP
;
1739 case LTTNG_KERNEL_SYSCALL
:
1740 events
[i
].type
= LTTNG_EVENT_SYSCALL
;
1748 * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
1750 static int cmd_disable_channel(struct ltt_session
*session
,
1751 int domain
, char *channel_name
)
1756 case LTTNG_DOMAIN_KERNEL
:
1757 ret
= channel_kernel_disable(session
->kernel_session
,
1759 if (ret
!= LTTCOMM_OK
) {
1763 kernel_wait_quiescent(kernel_tracer_fd
);
1765 case LTTNG_DOMAIN_UST_PID
:
1768 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
1779 * Copy channel from attributes and set it in the application channel list.
1781 static int copy_ust_channel_to_app(struct ltt_ust_session
*usess
,
1782 struct lttng_channel
*attr
, struct ust_app
*app
)
1785 struct ltt_ust_channel
*uchan
, *new_chan
;
1787 uchan
= trace_ust_get_channel_by_name(attr
->name
, usess
);
1788 if (uchan
== NULL
) {
1789 ret
= LTTCOMM_FATAL
;
1793 new_chan
= trace_ust_create_channel(attr
, usess
->path
);
1794 if (new_chan
== NULL
) {
1795 PERROR("malloc ltt_ust_channel");
1796 ret
= LTTCOMM_FATAL
;
1800 ret
= channel_ust_copy(new_chan
, uchan
);
1802 ret
= LTTCOMM_FATAL
;
1806 /* Add channel to the ust app channel list */
1807 cds_list_add(&new_chan
->list
, &app
->channels
.head
);
1808 app
->channels
.count
++;
1815 * Command LTTNG_ENABLE_CHANNEL processed by the client thread.
1817 static int cmd_enable_channel(struct ltt_session
*session
,
1818 struct lttng_domain
*domain
, struct lttng_channel
*attr
)
1822 switch (domain
->type
) {
1823 case LTTNG_DOMAIN_KERNEL
:
1825 struct ltt_kernel_channel
*kchan
;
1827 kchan
= trace_kernel_get_channel_by_name(attr
->name
,
1828 session
->kernel_session
);
1829 if (kchan
== NULL
) {
1830 ret
= channel_kernel_create(session
->kernel_session
,
1831 attr
, kernel_poll_pipe
[1]);
1833 ret
= channel_kernel_enable(session
->kernel_session
, kchan
);
1836 if (ret
!= LTTCOMM_OK
) {
1840 kernel_wait_quiescent(kernel_tracer_fd
);
1843 case LTTNG_DOMAIN_UST_PID
:
1846 struct ltt_ust_channel
*uchan
;
1847 struct ltt_ust_session
*usess
;
1848 struct ust_app
*app
;
1850 usess
= trace_ust_get_session_by_pid(&session
->ust_session_list
,
1852 if (usess
== NULL
) {
1853 ret
= LTTCOMM_UST_CHAN_NOT_FOUND
;
1857 app
= ust_app_get_by_pid(domain
->attr
.pid
);
1859 ret
= LTTCOMM_APP_NOT_FOUND
;
1864 uchan
= trace_ust_get_channel_by_name(attr
->name
, usess
);
1865 if (uchan
== NULL
) {
1866 ret
= channel_ust_create(usess
, attr
, sock
);
1868 ret
= channel_ust_enable(usess
, uchan
, sock
);
1871 if (ret
!= LTTCOMM_OK
) {
1875 ret
= copy_ust_channel_to_app(usess
, attr
, app
);
1876 if (ret
!= LTTCOMM_OK
) {
1880 DBG("UST channel %s created for app sock %d with pid %d",
1881 attr
->name
, app
->sock
, domain
->attr
.pid
);
1885 ret
= LTTCOMM_UNKNOWN_DOMAIN
;
1896 * Command LTTNG_DISABLE_EVENT processed by the client thread.
1898 static int cmd_disable_event(struct ltt_session
*session
, int domain
,
1899 char *channel_name
, char *event_name
)
1902 struct ltt_kernel_channel
*kchan
;
1905 case LTTNG_DOMAIN_KERNEL
:
1906 kchan
= trace_kernel_get_channel_by_name(channel_name
,
1907 session
->kernel_session
);
1908 if (kchan
== NULL
) {
1909 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
1913 ret
= event_kernel_disable(session
->kernel_session
, kchan
, event_name
);
1914 if (ret
!= LTTCOMM_OK
) {
1918 kernel_wait_quiescent(kernel_tracer_fd
);
1921 /* TODO: Userspace tracing */
1922 ret
= LTTCOMM_NOT_IMPLEMENTED
;
1933 * Command LTTNG_DISABLE_ALL_EVENT processed by the client thread.
1935 static int cmd_disable_event_all(struct ltt_session
*session
, int domain
,
1939 struct ltt_kernel_channel
*kchan
;
1942 case LTTNG_DOMAIN_KERNEL
:
1943 kchan
= trace_kernel_get_channel_by_name(channel_name
,
1944 session
->kernel_session
);
1945 if (kchan
== NULL
) {
1946 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
1950 ret
= event_kernel_disable_all(session
->kernel_session
, kchan
);
1951 if (ret
!= LTTCOMM_OK
) {
1955 kernel_wait_quiescent(kernel_tracer_fd
);
1958 /* TODO: Userspace tracing */
1959 ret
= LTTCOMM_NOT_IMPLEMENTED
;
1970 * Command LTTNG_ADD_CONTEXT processed by the client thread.
1972 static int cmd_add_context(struct ltt_session
*session
, int domain
,
1973 char *channel_name
, char *event_name
, struct lttng_event_context
*ctx
)
1978 case LTTNG_DOMAIN_KERNEL
:
1979 /* Add kernel context to kernel tracer */
1980 ret
= context_kernel_add(session
->kernel_session
, ctx
,
1981 event_name
, channel_name
);
1982 if (ret
!= LTTCOMM_OK
) {
1988 /* TODO: Userspace tracing */
1989 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2000 * Command LTTNG_ENABLE_EVENT processed by the client thread.
2002 static int cmd_enable_event(struct ltt_session
*session
, int domain
,
2003 char *channel_name
, struct lttng_event
*event
)
2006 struct ltt_kernel_channel
*kchan
;
2009 case LTTNG_DOMAIN_KERNEL
:
2010 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2011 session
->kernel_session
);
2012 if (kchan
== NULL
) {
2013 /* This call will notify the kernel thread */
2014 ret
= channel_kernel_create(session
->kernel_session
,
2015 NULL
, kernel_poll_pipe
[1]);
2016 if (ret
!= LTTCOMM_OK
) {
2021 /* Get the newly created kernel channel pointer */
2022 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2023 session
->kernel_session
);
2024 if (kchan
== NULL
) {
2025 /* This sould not happen... */
2026 ret
= LTTCOMM_FATAL
;
2030 ret
= event_kernel_enable(session
->kernel_session
, kchan
, event
);
2031 if (ret
!= LTTCOMM_OK
) {
2035 kernel_wait_quiescent(kernel_tracer_fd
);
2038 /* TODO: Userspace tracing */
2039 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2050 * Command LTTNG_ENABLE_ALL_EVENT processed by the client thread.
2052 static int cmd_enable_event_all(struct ltt_session
*session
, int domain
,
2053 char *channel_name
, int event_type
)
2056 struct ltt_kernel_channel
*kchan
;
2059 case LTTNG_DOMAIN_KERNEL
:
2060 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2061 session
->kernel_session
);
2062 if (kchan
== NULL
) {
2063 /* This call will notify the kernel thread */
2064 ret
= channel_kernel_create(session
->kernel_session
, NULL
,
2065 kernel_poll_pipe
[1]);
2066 if (ret
!= LTTCOMM_OK
) {
2071 /* Get the newly created kernel channel pointer */
2072 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2073 session
->kernel_session
);
2074 if (kchan
== NULL
) {
2075 /* This sould not happen... */
2076 ret
= LTTCOMM_FATAL
;
2080 if (event_type
== LTTNG_KERNEL_SYSCALL
) {
2081 ret
= event_kernel_enable_syscalls(session
->kernel_session
,
2082 kchan
, kernel_tracer_fd
);
2085 * This call enables all LTTNG_KERNEL_TRACEPOINTS and events
2086 * already registered to the channel.
2088 ret
= event_kernel_enable_all(session
->kernel_session
,
2089 kchan
, kernel_tracer_fd
);
2092 if (ret
!= LTTCOMM_OK
) {
2096 kernel_wait_quiescent(kernel_tracer_fd
);
2099 /* TODO: Userspace tracing */
2100 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2111 * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
2113 static ssize_t
cmd_list_tracepoints(int domain
, struct lttng_event
**events
)
2116 ssize_t nb_events
= 0;
2119 case LTTNG_DOMAIN_KERNEL
:
2120 nb_events
= kernel_list_events(kernel_tracer_fd
, events
);
2121 if (nb_events
< 0) {
2122 ret
= LTTCOMM_KERN_LIST_FAIL
;
2127 /* TODO: Userspace listing */
2128 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2135 /* Return negative value to differentiate return code */
2140 * Command LTTNG_START_TRACE processed by the client thread.
2142 static int cmd_start_trace(struct ltt_session
*session
)
2145 struct ltt_kernel_channel
*kchan
;
2146 struct ltt_kernel_session
*ksession
;
2149 ksession
= session
->kernel_session
;
2151 /* Kernel tracing */
2152 if (ksession
!= NULL
) {
2153 /* Open kernel metadata */
2154 if (ksession
->metadata
== NULL
) {
2155 ret
= kernel_open_metadata(ksession
, ksession
->trace_path
);
2157 ret
= LTTCOMM_KERN_META_FAIL
;
2162 /* Open kernel metadata stream */
2163 if (ksession
->metadata_stream_fd
== 0) {
2164 ret
= kernel_open_metadata_stream(ksession
);
2166 ERR("Kernel create metadata stream failed");
2167 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2172 /* For each channel */
2173 cds_list_for_each_entry(kchan
, &ksession
->channel_list
.head
, list
) {
2174 if (kchan
->stream_count
== 0) {
2175 ret
= kernel_open_channel_stream(kchan
);
2177 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2180 /* Update the stream global counter */
2181 ksession
->stream_count_global
+= ret
;
2185 /* Setup kernel consumer socket and send fds to it */
2186 ret
= init_kernel_tracing(ksession
);
2188 ret
= LTTCOMM_KERN_START_FAIL
;
2192 /* This start the kernel tracing */
2193 ret
= kernel_start_session(ksession
);
2195 ret
= LTTCOMM_KERN_START_FAIL
;
2199 /* Quiescent wait after starting trace */
2200 kernel_wait_quiescent(kernel_tracer_fd
);
2203 /* TODO: Start all UST traces */
2212 * Command LTTNG_STOP_TRACE processed by the client thread.
2214 static int cmd_stop_trace(struct ltt_session
*session
)
2217 struct ltt_kernel_channel
*kchan
;
2218 struct ltt_kernel_session
*ksession
;
2221 ksession
= session
->kernel_session
;
2224 if (ksession
!= NULL
) {
2225 DBG("Stop kernel tracing");
2227 /* Flush all buffers before stopping */
2228 ret
= kernel_metadata_flush_buffer(ksession
->metadata_stream_fd
);
2230 ERR("Kernel metadata flush failed");
2233 cds_list_for_each_entry(kchan
, &ksession
->channel_list
.head
, list
) {
2234 ret
= kernel_flush_buffer(kchan
);
2236 ERR("Kernel flush buffer error");
2240 ret
= kernel_stop_session(ksession
);
2242 ret
= LTTCOMM_KERN_STOP_FAIL
;
2246 kernel_wait_quiescent(kernel_tracer_fd
);
2249 /* TODO : User-space tracer */
2258 * Command LTTNG_CREATE_SESSION processed by the client thread.
2260 static int cmd_create_session(char *name
, char *path
)
2264 ret
= session_create(name
, path
);
2265 if (ret
!= LTTCOMM_OK
) {
2276 * Command LTTNG_DESTROY_SESSION processed by the client thread.
2278 static int cmd_destroy_session(struct ltt_session
*session
, char *name
)
2282 /* Clean kernel session teardown */
2283 teardown_kernel_session(session
);
2286 * Must notify the kernel thread here to update it's poll setin order
2287 * to remove the channel(s)' fd just destroyed.
2289 ret
= notify_thread_pipe(kernel_poll_pipe
[1]);
2291 perror("write kernel poll pipe");
2294 ret
= session_destroy(name
);
2300 * Command LTTNG_CALIBRATE processed by the client thread.
2302 static int cmd_calibrate(int domain
, struct lttng_calibrate
*calibrate
)
2307 case LTTNG_DOMAIN_KERNEL
:
2309 struct lttng_kernel_calibrate kcalibrate
;
2311 kcalibrate
.type
= calibrate
->type
;
2312 ret
= kernel_calibrate(kernel_tracer_fd
, &kcalibrate
);
2314 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
2320 /* TODO: Userspace tracing */
2321 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2332 * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
2334 static int cmd_register_consumer(struct ltt_session
*session
, int domain
,
2340 case LTTNG_DOMAIN_KERNEL
:
2341 /* Can't register a consumer if there is already one */
2342 if (session
->kernel_session
->consumer_fd
!= 0) {
2343 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
2347 sock
= lttcomm_connect_unix_sock(sock_path
);
2349 ret
= LTTCOMM_CONNECT_FAIL
;
2353 session
->kernel_session
->consumer_fd
= sock
;
2356 /* TODO: Userspace tracing */
2357 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2368 * Command LTTNG_LIST_DOMAINS processed by the client thread.
2370 static ssize_t
cmd_list_domains(struct ltt_session
*session
,
2371 struct lttng_domain
**domains
)
2376 if (session
->kernel_session
!= NULL
) {
2380 nb_dom
+= session
->ust_session_list
.count
;
2382 *domains
= malloc(nb_dom
* sizeof(struct lttng_domain
));
2383 if (*domains
== NULL
) {
2384 ret
= -LTTCOMM_FATAL
;
2388 (*domains
)[0].type
= LTTNG_DOMAIN_KERNEL
;
2390 /* TODO: User-space tracer domain support */
2399 * Command LTTNG_LIST_CHANNELS processed by the client thread.
2401 static ssize_t
cmd_list_channels(struct ltt_session
*session
,
2402 struct lttng_channel
**channels
)
2405 ssize_t nb_chan
= 0;
2407 if (session
->kernel_session
!= NULL
) {
2408 nb_chan
+= session
->kernel_session
->channel_count
;
2411 *channels
= malloc(nb_chan
* sizeof(struct lttng_channel
));
2412 if (*channels
== NULL
) {
2413 ret
= -LTTCOMM_FATAL
;
2417 list_lttng_channels(session
, *channels
);
2426 * Command LTTNG_LIST_EVENTS processed by the client thread.
2428 static ssize_t
cmd_list_events(struct ltt_session
*session
,
2429 char *channel_name
, struct lttng_event
**events
)
2432 ssize_t nb_event
= 0;
2433 struct ltt_kernel_channel
*kchan
= NULL
;
2435 if (session
->kernel_session
!= NULL
) {
2436 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2437 session
->kernel_session
);
2438 if (kchan
== NULL
) {
2439 ret
= -LTTCOMM_KERN_CHAN_NOT_FOUND
;
2442 nb_event
+= kchan
->event_count
;
2445 *events
= malloc(nb_event
* sizeof(struct lttng_event
));
2446 if (*events
== NULL
) {
2447 ret
= -LTTCOMM_FATAL
;
2451 list_lttng_events(kchan
, *events
);
2453 /* TODO: User-space tracer support */
2462 * Process the command requested by the lttng client within the command
2463 * context structure. This function make sure that the return structure (llm)
2464 * is set and ready for transmission before returning.
2466 * Return any error encountered or 0 for success.
2468 static int process_client_msg(struct command_ctx
*cmd_ctx
)
2470 int ret
= LTTCOMM_OK
;
2471 int need_tracing_session
= 1;
2473 DBG("Processing client command %d", cmd_ctx
->lsm
->cmd_type
);
2476 * Check for command that don't needs to allocate a returned payload. We do
2477 * this here so we don't have to make the call for no payload at each
2480 switch(cmd_ctx
->lsm
->cmd_type
) {
2481 case LTTNG_LIST_SESSIONS
:
2482 case LTTNG_LIST_TRACEPOINTS
:
2483 case LTTNG_LIST_DOMAINS
:
2484 case LTTNG_LIST_CHANNELS
:
2485 case LTTNG_LIST_EVENTS
:
2488 /* Setup lttng message with no payload */
2489 ret
= setup_lttng_msg(cmd_ctx
, 0);
2491 /* This label does not try to unlock the session */
2492 goto init_setup_error
;
2496 /* Commands that DO NOT need a session. */
2497 switch (cmd_ctx
->lsm
->cmd_type
) {
2498 case LTTNG_CALIBRATE
:
2499 case LTTNG_CREATE_SESSION
:
2500 case LTTNG_LIST_SESSIONS
:
2501 case LTTNG_LIST_TRACEPOINTS
:
2502 need_tracing_session
= 0;
2505 DBG("Getting session %s by name", cmd_ctx
->lsm
->session
.name
);
2506 cmd_ctx
->session
= session_find_by_name(cmd_ctx
->lsm
->session
.name
);
2507 if (cmd_ctx
->session
== NULL
) {
2508 if (cmd_ctx
->lsm
->session
.name
!= NULL
) {
2509 ret
= LTTCOMM_SESS_NOT_FOUND
;
2511 /* If no session name specified */
2512 ret
= LTTCOMM_SELECT_SESS
;
2516 /* Acquire lock for the session */
2517 session_lock(cmd_ctx
->session
);
2523 * Check domain type for specific "pre-action".
2525 switch (cmd_ctx
->lsm
->domain
.type
) {
2526 case LTTNG_DOMAIN_KERNEL
:
2527 /* Kernel tracer check */
2528 if (kernel_tracer_fd
== 0) {
2529 /* Basically, load kernel tracer modules */
2530 init_kernel_tracer();
2531 if (kernel_tracer_fd
== 0) {
2532 ret
= LTTCOMM_KERN_NA
;
2537 /* Need a session for kernel command */
2538 if (need_tracing_session
) {
2539 if (cmd_ctx
->session
->kernel_session
== NULL
) {
2540 ret
= create_kernel_session(cmd_ctx
->session
);
2542 ret
= LTTCOMM_KERN_SESS_FAIL
;
2547 /* Start the kernel consumer daemon */
2548 if (kconsumerd_pid
== 0 &&
2549 cmd_ctx
->lsm
->cmd_type
!= LTTNG_REGISTER_CONSUMER
) {
2550 ret
= start_kconsumerd();
2552 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
2558 case LTTNG_DOMAIN_UST_PID
:
2560 struct ltt_ust_session
*usess
;
2562 if (need_tracing_session
) {
2563 usess
= trace_ust_get_session_by_pid(
2564 &cmd_ctx
->session
->ust_session_list
,
2565 cmd_ctx
->lsm
->domain
.attr
.pid
);
2566 if (usess
== NULL
) {
2567 ret
= create_ust_session(cmd_ctx
->session
,
2568 &cmd_ctx
->lsm
->domain
);
2569 if (ret
!= LTTCOMM_OK
) {
2577 /* TODO Userspace tracer */
2581 /* Process by command type */
2582 switch (cmd_ctx
->lsm
->cmd_type
) {
2583 case LTTNG_ADD_CONTEXT
:
2585 ret
= cmd_add_context(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2586 cmd_ctx
->lsm
->u
.context
.channel_name
,
2587 cmd_ctx
->lsm
->u
.context
.event_name
,
2588 &cmd_ctx
->lsm
->u
.context
.ctx
);
2591 case LTTNG_DISABLE_CHANNEL
:
2593 ret
= cmd_disable_channel(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2594 cmd_ctx
->lsm
->u
.disable
.channel_name
);
2597 case LTTNG_DISABLE_EVENT
:
2599 ret
= cmd_disable_event(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2600 cmd_ctx
->lsm
->u
.disable
.channel_name
,
2601 cmd_ctx
->lsm
->u
.disable
.name
);
2605 case LTTNG_DISABLE_ALL_EVENT
:
2607 DBG("Disabling all kernel event");
2609 ret
= cmd_disable_event_all(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2610 cmd_ctx
->lsm
->u
.disable
.channel_name
);
2613 case LTTNG_ENABLE_CHANNEL
:
2615 ret
= cmd_enable_channel(cmd_ctx
->session
, &cmd_ctx
->lsm
->domain
,
2616 &cmd_ctx
->lsm
->u
.channel
.chan
);
2619 case LTTNG_ENABLE_EVENT
:
2621 ret
= cmd_enable_event(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2622 cmd_ctx
->lsm
->u
.enable
.channel_name
,
2623 &cmd_ctx
->lsm
->u
.enable
.event
);
2626 case LTTNG_ENABLE_ALL_EVENT
:
2628 DBG("Enabling all kernel event");
2630 ret
= cmd_enable_event_all(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2631 cmd_ctx
->lsm
->u
.enable
.channel_name
,
2632 cmd_ctx
->lsm
->u
.enable
.event
.type
);
2635 case LTTNG_LIST_TRACEPOINTS
:
2637 struct lttng_event
*events
;
2640 nb_events
= cmd_list_tracepoints(cmd_ctx
->lsm
->domain
.type
, &events
);
2641 if (nb_events
< 0) {
2647 * Setup lttng message with payload size set to the event list size in
2648 * bytes and then copy list into the llm payload.
2650 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_event
) * nb_events
);
2656 /* Copy event list into message payload */
2657 memcpy(cmd_ctx
->llm
->payload
, events
,
2658 sizeof(struct lttng_event
) * nb_events
);
2665 case LTTNG_START_TRACE
:
2667 ret
= cmd_start_trace(cmd_ctx
->session
);
2670 case LTTNG_STOP_TRACE
:
2672 ret
= cmd_stop_trace(cmd_ctx
->session
);
2675 case LTTNG_CREATE_SESSION
:
2677 ret
= cmd_create_session(cmd_ctx
->lsm
->session
.name
,
2678 cmd_ctx
->lsm
->session
.path
);
2681 case LTTNG_DESTROY_SESSION
:
2683 ret
= cmd_destroy_session(cmd_ctx
->session
,
2684 cmd_ctx
->lsm
->session
.name
);
2687 case LTTNG_LIST_DOMAINS
:
2690 struct lttng_domain
*domains
;
2692 nb_dom
= cmd_list_domains(cmd_ctx
->session
, &domains
);
2698 ret
= setup_lttng_msg(cmd_ctx
, nb_dom
* sizeof(struct lttng_domain
));
2703 /* Copy event list into message payload */
2704 memcpy(cmd_ctx
->llm
->payload
, domains
,
2705 nb_dom
* sizeof(struct lttng_domain
));
2712 case LTTNG_LIST_CHANNELS
:
2715 struct lttng_channel
*channels
;
2717 nb_chan
= cmd_list_channels(cmd_ctx
->session
, &channels
);
2723 ret
= setup_lttng_msg(cmd_ctx
, nb_chan
* sizeof(struct lttng_channel
));
2728 /* Copy event list into message payload */
2729 memcpy(cmd_ctx
->llm
->payload
, channels
,
2730 nb_chan
* sizeof(struct lttng_channel
));
2737 case LTTNG_LIST_EVENTS
:
2740 struct lttng_event
*events
= NULL
;
2742 nb_event
= cmd_list_events(cmd_ctx
->session
,
2743 cmd_ctx
->lsm
->u
.list
.channel_name
, &events
);
2749 ret
= setup_lttng_msg(cmd_ctx
, nb_event
* sizeof(struct lttng_event
));
2754 /* Copy event list into message payload */
2755 memcpy(cmd_ctx
->llm
->payload
, events
,
2756 nb_event
* sizeof(struct lttng_event
));
2763 case LTTNG_LIST_SESSIONS
:
2765 session_lock_list();
2767 if (session_list_ptr
->count
== 0) {
2768 ret
= LTTCOMM_NO_SESSION
;
2769 session_unlock_list();
2773 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_session
) *
2774 session_list_ptr
->count
);
2776 session_unlock_list();
2780 /* Filled the session array */
2781 list_lttng_sessions((struct lttng_session
*)(cmd_ctx
->llm
->payload
));
2783 session_unlock_list();
2788 case LTTNG_CALIBRATE
:
2790 ret
= cmd_calibrate(cmd_ctx
->lsm
->domain
.type
,
2791 &cmd_ctx
->lsm
->u
.calibrate
);
2794 case LTTNG_REGISTER_CONSUMER
:
2796 ret
= cmd_register_consumer(cmd_ctx
->session
, cmd_ctx
->lsm
->domain
.type
,
2797 cmd_ctx
->lsm
->u
.reg
.path
);
2806 if (cmd_ctx
->llm
== NULL
) {
2807 DBG("Missing llm structure. Allocating one.");
2808 if (setup_lttng_msg(cmd_ctx
, 0) < 0) {
2812 /* Set return code */
2813 cmd_ctx
->llm
->ret_code
= ret
;
2815 if (cmd_ctx
->session
) {
2816 session_unlock(cmd_ctx
->session
);
2823 * This thread manage all clients request using the unix client socket for
2826 static void *thread_manage_clients(void *data
)
2828 int sock
= 0, ret
, i
, pollfd
;
2829 uint32_t revents
, nb_fd
;
2830 struct command_ctx
*cmd_ctx
= NULL
;
2831 struct lttng_poll_event events
;
2833 DBG("[thread] Manage client started");
2835 ret
= lttcomm_listen_unix_sock(client_sock
);
2841 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2842 * more will be added to this poll set.
2844 ret
= create_thread_poll_set(&events
, 2);
2849 /* Add the application registration socket */
2850 ret
= lttng_poll_add(&events
, client_sock
, LPOLLIN
| LPOLLPRI
);
2856 * Notify parent pid that we are ready to accept command for client side.
2858 if (opt_sig_parent
) {
2859 kill(ppid
, SIGCHLD
);
2863 DBG("Accepting client command ...");
2865 nb_fd
= LTTNG_POLL_GETNB(&events
);
2867 /* Inifinite blocking call, waiting for transmission */
2868 ret
= lttng_poll_wait(&events
, -1);
2873 for (i
= 0; i
< nb_fd
; i
++) {
2874 /* Fetch once the poll data */
2875 revents
= LTTNG_POLL_GETEV(&events
, i
);
2876 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
2878 /* Thread quit pipe has been closed. Killing thread. */
2879 ret
= check_thread_quit_pipe(pollfd
, revents
);
2884 /* Event on the registration socket */
2885 if (pollfd
== client_sock
) {
2886 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
2887 ERR("Client socket poll error");
2893 DBG("Wait for client response");
2895 sock
= lttcomm_accept_unix_sock(client_sock
);
2900 /* Allocate context command to process the client request */
2901 cmd_ctx
= malloc(sizeof(struct command_ctx
));
2902 if (cmd_ctx
== NULL
) {
2903 perror("malloc cmd_ctx");
2907 /* Allocate data buffer for reception */
2908 cmd_ctx
->lsm
= malloc(sizeof(struct lttcomm_session_msg
));
2909 if (cmd_ctx
->lsm
== NULL
) {
2910 perror("malloc cmd_ctx->lsm");
2914 cmd_ctx
->llm
= NULL
;
2915 cmd_ctx
->session
= NULL
;
2918 * Data is received from the lttng client. The struct
2919 * lttcomm_session_msg (lsm) contains the command and data request of
2922 DBG("Receiving data from client ...");
2923 ret
= lttcomm_recv_unix_sock(sock
, cmd_ctx
->lsm
,
2924 sizeof(struct lttcomm_session_msg
));
2926 DBG("Nothing recv() from client... continuing");
2932 // TODO: Validate cmd_ctx including sanity check for
2933 // security purpose.
2936 * This function dispatch the work to the kernel or userspace tracer
2937 * libs and fill the lttcomm_lttng_msg data structure of all the needed
2938 * informations for the client. The command context struct contains
2939 * everything this function may needs.
2941 ret
= process_client_msg(cmd_ctx
);
2944 * TODO: Inform client somehow of the fatal error. At
2945 * this point, ret < 0 means that a malloc failed
2946 * (ENOMEM). Error detected but still accept command.
2948 clean_command_ctx(&cmd_ctx
);
2952 DBG("Sending response (size: %d, retcode: %s)",
2953 cmd_ctx
->lttng_msg_size
,
2954 lttng_get_readable_code(-cmd_ctx
->llm
->ret_code
));
2955 ret
= send_unix_sock(sock
, cmd_ctx
->llm
, cmd_ctx
->lttng_msg_size
);
2957 ERR("Failed to send data back to client");
2960 clean_command_ctx(&cmd_ctx
);
2962 /* End of transmission */
2967 DBG("Client thread dying");
2968 unlink(client_unix_sock_path
);
2972 lttng_poll_clean(&events
);
2973 clean_command_ctx(&cmd_ctx
);
2979 * usage function on stderr
2981 static void usage(void)
2983 fprintf(stderr
, "Usage: %s OPTIONS\n\nOptions:\n", progname
);
2984 fprintf(stderr
, " -h, --help Display this usage.\n");
2985 fprintf(stderr
, " -c, --client-sock PATH Specify path for the client unix socket\n");
2986 fprintf(stderr
, " -a, --apps-sock PATH Specify path for apps unix socket\n");
2987 fprintf(stderr
, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
2988 fprintf(stderr
, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
2989 fprintf(stderr
, " -d, --daemonize Start as a daemon.\n");
2990 fprintf(stderr
, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
2991 fprintf(stderr
, " -V, --version Show version number.\n");
2992 fprintf(stderr
, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
2993 fprintf(stderr
, " -q, --quiet No output at all.\n");
2994 fprintf(stderr
, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
2995 fprintf(stderr
, " --verbose-kconsumerd Verbose mode for kconsumerd. Activate DBG() macro.\n");
2999 * daemon argument parsing
3001 static int parse_args(int argc
, char **argv
)
3005 static struct option long_options
[] = {
3006 { "client-sock", 1, 0, 'c' },
3007 { "apps-sock", 1, 0, 'a' },
3008 { "kconsumerd-cmd-sock", 1, 0, 0 },
3009 { "kconsumerd-err-sock", 1, 0, 0 },
3010 { "daemonize", 0, 0, 'd' },
3011 { "sig-parent", 0, 0, 'S' },
3012 { "help", 0, 0, 'h' },
3013 { "group", 1, 0, 'g' },
3014 { "version", 0, 0, 'V' },
3015 { "quiet", 0, 0, 'q' },
3016 { "verbose", 0, 0, 'v' },
3017 { "verbose-kconsumerd", 0, 0, 'Z' },
3022 int option_index
= 0;
3023 c
= getopt_long(argc
, argv
, "dhqvVS" "a:c:g:s:E:C:Z",
3024 long_options
, &option_index
);
3031 fprintf(stderr
, "option %s", long_options
[option_index
].name
);
3033 fprintf(stderr
, " with arg %s\n", optarg
);
3037 snprintf(client_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3040 snprintf(apps_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3046 opt_tracing_group
= strdup(optarg
);
3052 fprintf(stdout
, "%s\n", VERSION
);
3058 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3061 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
, "%s", optarg
);
3067 /* Verbose level can increase using multiple -v */
3071 opt_verbose_kconsumerd
+= 1;
3074 /* Unknown option or other error.
3075 * Error is printed by getopt, just return */
3084 * Creates the two needed socket by the daemon.
3085 * apps_sock - The communication socket for all UST apps.
3086 * client_sock - The communication of the cli tool (lttng).
3088 static int init_daemon_socket(void)
3093 old_umask
= umask(0);
3095 /* Create client tool unix socket */
3096 client_sock
= lttcomm_create_unix_sock(client_unix_sock_path
);
3097 if (client_sock
< 0) {
3098 ERR("Create unix sock failed: %s", client_unix_sock_path
);
3103 /* File permission MUST be 660 */
3104 ret
= chmod(client_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
3106 ERR("Set file permissions failed: %s", client_unix_sock_path
);
3111 /* Create the application unix socket */
3112 apps_sock
= lttcomm_create_unix_sock(apps_unix_sock_path
);
3113 if (apps_sock
< 0) {
3114 ERR("Create unix sock failed: %s", apps_unix_sock_path
);
3119 /* File permission MUST be 666 */
3120 ret
= chmod(apps_unix_sock_path
,
3121 S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
| S_IROTH
| S_IWOTH
);
3123 ERR("Set file permissions failed: %s", apps_unix_sock_path
);
3134 * Check if the global socket is available, and if a daemon is answering at the
3135 * other side. If yes, error is returned.
3137 static int check_existing_daemon(void)
3139 if (access(client_unix_sock_path
, F_OK
) < 0 &&
3140 access(apps_unix_sock_path
, F_OK
) < 0) {
3144 /* Is there anybody out there ? */
3145 if (lttng_session_daemon_alive()) {
3153 * Set the tracing group gid onto the client socket.
3155 * Race window between mkdir and chown is OK because we are going from more
3156 * permissive (root.root) to les permissive (root.tracing).
3158 static int set_permissions(void)
3163 gid
= allowed_group();
3166 WARN("No tracing group detected");
3169 ERR("Missing tracing group. Aborting execution.");
3175 /* Set lttng run dir */
3176 ret
= chown(LTTNG_RUNDIR
, 0, gid
);
3178 ERR("Unable to set group on " LTTNG_RUNDIR
);
3182 /* lttng client socket path */
3183 ret
= chown(client_unix_sock_path
, 0, gid
);
3185 ERR("Unable to set group on %s", client_unix_sock_path
);
3189 /* kconsumerd error socket path */
3190 ret
= chown(kconsumerd_err_unix_sock_path
, 0, gid
);
3192 ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path
);
3196 DBG("All permissions are set");
3203 * Create the pipe used to wake up the kernel thread.
3205 static int create_kernel_poll_pipe(void)
3207 return pipe2(kernel_poll_pipe
, O_CLOEXEC
);
3211 * Create the application command pipe to wake thread_manage_apps.
3213 static int create_apps_cmd_pipe(void)
3215 return pipe2(apps_cmd_pipe
, O_CLOEXEC
);
3219 * Create the lttng run directory needed for all global sockets and pipe.
3221 static int create_lttng_rundir(void)
3225 ret
= mkdir(LTTNG_RUNDIR
, S_IRWXU
| S_IRWXG
);
3227 if (errno
!= EEXIST
) {
3228 ERR("Unable to create " LTTNG_RUNDIR
);
3240 * Setup sockets and directory needed by the kconsumerd communication with the
3243 static int set_kconsumerd_sockets(void)
3247 if (strlen(kconsumerd_err_unix_sock_path
) == 0) {
3248 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
,
3249 KCONSUMERD_ERR_SOCK_PATH
);
3252 if (strlen(kconsumerd_cmd_unix_sock_path
) == 0) {
3253 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
,
3254 KCONSUMERD_CMD_SOCK_PATH
);
3257 ret
= mkdir(KCONSUMERD_PATH
, S_IRWXU
| S_IRWXG
);
3259 if (errno
!= EEXIST
) {
3260 ERR("Failed to create " KCONSUMERD_PATH
);
3266 /* Create the kconsumerd error unix socket */
3267 kconsumerd_err_sock
=
3268 lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path
);
3269 if (kconsumerd_err_sock
< 0) {
3270 ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path
);
3275 /* File permission MUST be 660 */
3276 ret
= chmod(kconsumerd_err_unix_sock_path
,
3277 S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
3279 ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path
);
3289 * Signal handler for the daemon
3291 * Simply stop all worker threads, leaving main() return gracefully after
3292 * joining all threads and calling cleanup().
3294 static void sighandler(int sig
)
3298 DBG("SIGPIPE catched");
3301 DBG("SIGINT catched");
3305 DBG("SIGTERM catched");
3314 * Setup signal handler for :
3315 * SIGINT, SIGTERM, SIGPIPE
3317 static int set_signal_handler(void)
3320 struct sigaction sa
;
3323 if ((ret
= sigemptyset(&sigset
)) < 0) {
3324 perror("sigemptyset");
3328 sa
.sa_handler
= sighandler
;
3329 sa
.sa_mask
= sigset
;
3331 if ((ret
= sigaction(SIGTERM
, &sa
, NULL
)) < 0) {
3332 perror("sigaction");
3336 if ((ret
= sigaction(SIGINT
, &sa
, NULL
)) < 0) {
3337 perror("sigaction");
3341 if ((ret
= sigaction(SIGPIPE
, &sa
, NULL
)) < 0) {
3342 perror("sigaction");
3346 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3352 * Set open files limit to unlimited. This daemon can open a large number of
3353 * file descriptors in order to consumer multiple kernel traces.
3355 static void set_ulimit(void)
3360 /* The kernel does not allowed an infinite limit for open files */
3361 lim
.rlim_cur
= 65535;
3362 lim
.rlim_max
= 65535;
3364 ret
= setrlimit(RLIMIT_NOFILE
, &lim
);
3366 perror("failed to set open files limit");
3373 int main(int argc
, char **argv
)
3377 const char *home_path
;
3379 /* Create thread quit pipe */
3380 if ((ret
= init_thread_quit_pipe()) < 0) {
3384 /* Parse arguments */
3386 if ((ret
= parse_args(argc
, argv
) < 0)) {
3399 /* Check if daemon is UID = 0 */
3400 is_root
= !getuid();
3403 ret
= create_lttng_rundir();
3408 if (strlen(apps_unix_sock_path
) == 0) {
3409 snprintf(apps_unix_sock_path
, PATH_MAX
,
3410 DEFAULT_GLOBAL_APPS_UNIX_SOCK
);
3413 if (strlen(client_unix_sock_path
) == 0) {
3414 snprintf(client_unix_sock_path
, PATH_MAX
,
3415 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
);
3418 /* Set global SHM for ust */
3419 if (strlen(wait_shm_path
) == 0) {
3420 snprintf(wait_shm_path
, PATH_MAX
,
3421 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH
);
3424 home_path
= get_home_dir();
3425 if (home_path
== NULL
) {
3426 /* TODO: Add --socket PATH option */
3427 ERR("Can't get HOME directory for sockets creation.");
3432 if (strlen(apps_unix_sock_path
) == 0) {
3433 snprintf(apps_unix_sock_path
, PATH_MAX
,
3434 DEFAULT_HOME_APPS_UNIX_SOCK
, home_path
);
3437 /* Set the cli tool unix socket path */
3438 if (strlen(client_unix_sock_path
) == 0) {
3439 snprintf(client_unix_sock_path
, PATH_MAX
,
3440 DEFAULT_HOME_CLIENT_UNIX_SOCK
, home_path
);
3443 /* Set global SHM for ust */
3444 if (strlen(wait_shm_path
) == 0) {
3445 snprintf(wait_shm_path
, PATH_MAX
,
3446 DEFAULT_HOME_APPS_WAIT_SHM_PATH
, geteuid());
3450 DBG("Client socket path %s", client_unix_sock_path
);
3451 DBG("Application socket path %s", apps_unix_sock_path
);
3454 * See if daemon already exist.
3456 if ((ret
= check_existing_daemon()) < 0) {
3457 ERR("Already running daemon.\n");
3459 * We do not goto exit because we must not cleanup()
3460 * because a daemon is already running.
3465 /* After this point, we can safely call cleanup() with "goto exit" */
3468 * These actions must be executed as root. We do that *after* setting up
3469 * the sockets path because we MUST make the check for another daemon using
3470 * those paths *before* trying to set the kernel consumer sockets and init
3474 ret
= set_kconsumerd_sockets();
3479 /* Setup kernel tracer */
3480 init_kernel_tracer();
3482 /* Set ulimit for open files */
3486 if ((ret
= set_signal_handler()) < 0) {
3490 /* Setup the needed unix socket */
3491 if ((ret
= init_daemon_socket()) < 0) {
3495 /* Set credentials to socket */
3496 if (is_root
&& ((ret
= set_permissions()) < 0)) {
3500 /* Get parent pid if -S, --sig-parent is specified. */
3501 if (opt_sig_parent
) {
3505 /* Setup the kernel pipe for waking up the kernel thread */
3506 if ((ret
= create_kernel_poll_pipe()) < 0) {
3510 /* Setup the thread apps communication pipe. */
3511 if ((ret
= create_apps_cmd_pipe()) < 0) {
3515 /* Init UST command queue. */
3516 cds_wfq_init(&ust_cmd_queue
.queue
);
3519 * Get session list pointer. This pointer MUST NOT be free(). This list is
3520 * statically declared in session.c
3522 session_list_ptr
= session_get_list();
3524 /* Set up max poll set size */
3525 lttng_poll_set_max_size();
3527 /* Create thread to manage the client socket */
3528 ret
= pthread_create(&client_thread
, NULL
,
3529 thread_manage_clients
, (void *) NULL
);
3531 perror("pthread_create clients");
3535 /* Create thread to dispatch registration */
3536 ret
= pthread_create(&dispatch_thread
, NULL
,
3537 thread_dispatch_ust_registration
, (void *) NULL
);
3539 perror("pthread_create dispatch");
3543 /* Create thread to manage application registration. */
3544 ret
= pthread_create(®_apps_thread
, NULL
,
3545 thread_registration_apps
, (void *) NULL
);
3547 perror("pthread_create registration");
3551 /* Create thread to manage application socket */
3552 ret
= pthread_create(&apps_thread
, NULL
,
3553 thread_manage_apps
, (void *) NULL
);
3555 perror("pthread_create apps");
3559 /* Create kernel thread to manage kernel event */
3560 ret
= pthread_create(&kernel_thread
, NULL
,
3561 thread_manage_kernel
, (void *) NULL
);
3563 perror("pthread_create kernel");
3567 ret
= pthread_join(kernel_thread
, &status
);
3569 perror("pthread_join");
3570 goto error
; /* join error, exit without cleanup */
3574 ret
= pthread_join(apps_thread
, &status
);
3576 perror("pthread_join");
3577 goto error
; /* join error, exit without cleanup */
3581 ret
= pthread_join(reg_apps_thread
, &status
);
3583 perror("pthread_join");
3584 goto error
; /* join error, exit without cleanup */
3588 ret
= pthread_join(dispatch_thread
, &status
);
3590 perror("pthread_join");
3591 goto error
; /* join error, exit without cleanup */
3595 ret
= pthread_join(client_thread
, &status
);
3597 perror("pthread_join");
3598 goto error
; /* join error, exit without cleanup */
3601 ret
= join_kconsumerd_thread();
3603 perror("join_kconsumerd");
3604 goto error
; /* join error, exit without cleanup */
3610 * cleanup() is called when no other thread is running.