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
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; only version 2
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
26 #include <semaphore.h>
32 #include <sys/mount.h>
33 #include <sys/resource.h>
34 #include <sys/socket.h>
36 #include <sys/types.h>
38 #include <urcu/futex.h>
41 #include <ltt-kconsumerd.h>
42 #include <lttng-sessiond-comm.h>
43 #include <lttng/lttng-kconsumerd.h>
46 #include "compat/poll.h"
49 #include "kernel-ctl.h"
50 #include "ltt-sessiond.h"
52 #include "traceable-app.h"
57 #include "benchmark.h"
60 const char default_home_dir
[] = DEFAULT_HOME_DIR
;
61 const char default_tracing_group
[] = LTTNG_DEFAULT_TRACING_GROUP
;
62 const char default_ust_sock_dir
[] = DEFAULT_UST_SOCK_DIR
;
63 const char default_global_apps_pipe
[] = DEFAULT_GLOBAL_APPS_PIPE
;
66 int opt_verbose
; /* Not static for lttngerr.h */
67 int opt_verbose_kconsumerd
; /* Not static for lttngerr.h */
68 int opt_quiet
; /* Not static for lttngerr.h */
71 const char *opt_tracing_group
;
72 static int opt_sig_parent
;
73 static int opt_daemon
;
74 static int is_root
; /* Set to 1 if the daemon is running as root */
75 static pid_t ppid
; /* Parent PID for --sig-parent option */
76 static pid_t kconsumerd_pid
;
77 static int dispatch_thread_exit
;
79 static char apps_unix_sock_path
[PATH_MAX
]; /* Global application Unix socket path */
80 static char client_unix_sock_path
[PATH_MAX
]; /* Global client Unix socket path */
81 static char kconsumerd_err_unix_sock_path
[PATH_MAX
]; /* kconsumerd error Unix socket path */
82 static char kconsumerd_cmd_unix_sock_path
[PATH_MAX
]; /* kconsumerd command Unix socket path */
83 static char wait_shm_path
[PATH_MAX
]; /* global wait shm path for UST */
86 static int client_sock
;
88 static int kconsumerd_err_sock
;
89 static int kconsumerd_cmd_sock
;
90 static int kernel_tracer_fd
;
91 static int kernel_poll_pipe
[2];
94 * Quit pipe for all threads. This permits a single cancellation point
95 * for all threads when receiving an event on the pipe.
97 static int thread_quit_pipe
[2];
100 * This pipe is used to inform the thread managing application communication
101 * that a command is queued and ready to be processed.
103 static int apps_cmd_pipe
[2];
105 /* Pthread, Mutexes and Semaphores */
106 static pthread_t kconsumerd_thread
;
107 static pthread_t apps_thread
;
108 static pthread_t reg_apps_thread
;
109 static pthread_t client_thread
;
110 static pthread_t kernel_thread
;
111 static pthread_t dispatch_thread
;
112 static sem_t kconsumerd_sem
;
115 /* Mutex to control kconsumerd pid assignation */
116 static pthread_mutex_t kconsumerd_pid_mutex
;
119 * UST registration command queue. This queue is tied with a futex and uses a N
120 * wakers / 1 waiter implemented and detailed in futex.c/.h
122 * The thread_manage_apps and thread_dispatch_ust_registration interact with
123 * this queue and the wait/wake scheme.
125 static struct ust_cmd_queue ust_cmd_queue
;
128 * Pointer initialized before thread creation.
130 * This points to the tracing session list containing the session count and a
131 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
132 * MUST NOT be taken if you call a public function in session.c.
134 * The lock is nested inside the structure: session_list_ptr->lock. Please use
135 * lock_session_list and unlock_session_list for lock acquisition.
137 static struct ltt_session_list
*session_list_ptr
;
140 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
142 static int create_thread_poll_set(struct lttng_poll_event
*events
,
147 if (events
== NULL
|| size
== 0) {
152 ret
= lttng_poll_create(events
, size
, LTTNG_CLOEXEC
);
158 ret
= lttng_poll_add(events
, thread_quit_pipe
[0], LPOLLIN
);
170 * Check if the thread quit pipe was triggered.
172 * Return 1 if it was triggered else 0;
174 static int check_thread_quit_pipe(int fd
, uint32_t events
)
176 if (fd
== thread_quit_pipe
[0] && (events
& LPOLLIN
)) {
184 * Remove modules in reverse load order.
186 static int modprobe_remove_kernel_modules(void)
191 for (i
= ARRAY_SIZE(kernel_modules_list
) - 1; i
>= 0; i
--) {
192 ret
= snprintf(modprobe
, sizeof(modprobe
),
193 "/sbin/modprobe --remove --quiet %s",
194 kernel_modules_list
[i
].name
);
196 perror("snprintf modprobe --remove");
199 modprobe
[sizeof(modprobe
) - 1] = '\0';
200 ret
= system(modprobe
);
202 ERR("Unable to launch modprobe --remove for module %s",
203 kernel_modules_list
[i
].name
);
204 } else if (kernel_modules_list
[i
].required
205 && WEXITSTATUS(ret
) != 0) {
206 ERR("Unable to remove module %s",
207 kernel_modules_list
[i
].name
);
209 DBG("Modprobe removal successful %s",
210 kernel_modules_list
[i
].name
);
219 * Return group ID of the tracing group or -1 if not found.
221 static gid_t
allowed_group(void)
225 if (opt_tracing_group
) {
226 grp
= getgrnam(opt_tracing_group
);
228 grp
= getgrnam(default_tracing_group
);
238 * Init thread quit pipe.
240 * Return -1 on error or 0 if all pipes are created.
242 static int init_thread_quit_pipe(void)
246 ret
= pipe2(thread_quit_pipe
, O_CLOEXEC
);
248 perror("thread quit pipe");
257 * Complete teardown of a kernel session. This free all data structure related
258 * to a kernel session and update counter.
260 static void teardown_kernel_session(struct ltt_session
*session
)
262 if (session
->kernel_session
!= NULL
) {
263 DBG("Tearing down kernel session");
266 * If a custom kernel consumer was registered, close the socket before
267 * tearing down the complete kernel session structure
269 if (session
->kernel_session
->consumer_fd
!= kconsumerd_cmd_sock
) {
270 lttcomm_close_unix_sock(session
->kernel_session
->consumer_fd
);
273 trace_kernel_destroy_session(session
->kernel_session
);
274 /* Extra precaution */
275 session
->kernel_session
= NULL
;
280 * Stop all threads by closing the thread quit pipe.
282 static void stop_threads(void)
286 /* Stopping all threads */
287 DBG("Terminating all threads");
288 ret
= write(thread_quit_pipe
[1], "!", 1);
290 ERR("write error on thread quit pipe");
293 /* Dispatch thread */
294 dispatch_thread_exit
= 1;
295 futex_nto1_wake(&ust_cmd_queue
.futex
);
301 static void cleanup(void)
305 struct ltt_session
*sess
, *stmp
;
310 MSG("%c[%d;%dm*** assert failed *** ==> %c[%dm%c[%d;%dm"
311 "Matthew, BEET driven development works!%c[%dm",
312 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
316 DBG("Removing %s directory", LTTNG_RUNDIR
);
317 ret
= asprintf(&cmd
, "rm -rf " LTTNG_RUNDIR
);
319 ERR("asprintf failed. Something is really wrong!");
322 /* Remove lttng run directory */
325 ERR("Unable to clean " LTTNG_RUNDIR
);
329 DBG("Cleaning up all session");
331 /* Destroy session list mutex */
332 if (session_list_ptr
!= NULL
) {
333 pthread_mutex_destroy(&session_list_ptr
->lock
);
335 /* Cleanup ALL session */
336 cds_list_for_each_entry_safe(sess
, stmp
, &session_list_ptr
->head
, list
) {
337 teardown_kernel_session(sess
);
338 // TODO complete session cleanup (including UST)
342 DBG("Closing all UST sockets");
343 clean_traceable_apps_list();
345 pthread_mutex_destroy(&kconsumerd_pid_mutex
);
347 DBG("Closing kernel fd");
348 close(kernel_tracer_fd
);
351 DBG("Unloading kernel modules");
352 modprobe_remove_kernel_modules();
355 close(thread_quit_pipe
[0]);
356 close(thread_quit_pipe
[1]);
358 /* OUTPUT BENCHMARK RESULTS */
361 if (getenv("BENCH_UST_NOTIFY")) {
362 bench_print_ust_notification();
365 if (getenv("BENCH_UST_REGISTER")) {
366 bench_print_ust_register();
369 if (getenv("BENCH_BOOT_PROCESS")) {
370 bench_print_boot_process();
378 * Send data on a unix socket using the liblttsessiondcomm API.
380 * Return lttcomm error code.
382 static int send_unix_sock(int sock
, void *buf
, size_t len
)
384 /* Check valid length */
389 return lttcomm_send_unix_sock(sock
, buf
, len
);
393 * Free memory of a command context structure.
395 static void clean_command_ctx(struct command_ctx
**cmd_ctx
)
397 DBG("Clean command context structure");
399 if ((*cmd_ctx
)->llm
) {
400 free((*cmd_ctx
)->llm
);
402 if ((*cmd_ctx
)->lsm
) {
403 free((*cmd_ctx
)->lsm
);
411 * Send all stream fds of kernel channel to the consumer.
413 static int send_kconsumerd_channel_fds(int sock
, struct ltt_kernel_channel
*channel
)
417 struct ltt_kernel_stream
*stream
;
418 struct lttcomm_kconsumerd_header lkh
;
419 struct lttcomm_kconsumerd_msg lkm
;
421 DBG("Sending fds of channel %s to kernel consumer", channel
->channel
->name
);
423 nb_fd
= channel
->stream_count
;
426 lkh
.payload_size
= nb_fd
* sizeof(struct lttcomm_kconsumerd_msg
);
427 lkh
.cmd_type
= ADD_STREAM
;
429 DBG("Sending kconsumerd header");
431 ret
= lttcomm_send_unix_sock(sock
, &lkh
, sizeof(struct lttcomm_kconsumerd_header
));
433 perror("send kconsumerd header");
437 cds_list_for_each_entry(stream
, &channel
->stream_list
.head
, list
) {
438 if (stream
->fd
!= 0) {
440 lkm
.state
= stream
->state
;
441 lkm
.max_sb_size
= channel
->channel
->attr
.subbuf_size
;
442 lkm
.output
= channel
->channel
->attr
.output
;
443 strncpy(lkm
.path_name
, stream
->pathname
, PATH_MAX
);
444 lkm
.path_name
[PATH_MAX
- 1] = '\0';
446 DBG("Sending fd %d to kconsumerd", lkm
.fd
);
448 ret
= lttcomm_send_fds_unix_sock(sock
, &lkm
, &lkm
.fd
, 1, sizeof(lkm
));
450 perror("send kconsumerd fd");
456 DBG("Kconsumerd channel fds sent");
465 * Send all stream fds of the kernel session to the consumer.
467 static int send_kconsumerd_fds(struct ltt_kernel_session
*session
)
470 struct ltt_kernel_channel
*chan
;
471 struct lttcomm_kconsumerd_header lkh
;
472 struct lttcomm_kconsumerd_msg lkm
;
475 lkh
.payload_size
= sizeof(struct lttcomm_kconsumerd_msg
);
476 lkh
.cmd_type
= ADD_STREAM
;
478 DBG("Sending kconsumerd header for metadata");
480 ret
= lttcomm_send_unix_sock(session
->consumer_fd
, &lkh
, sizeof(struct lttcomm_kconsumerd_header
));
482 perror("send kconsumerd header");
486 DBG("Sending metadata stream fd");
488 /* Extra protection. It's NOT suppose to be set to 0 at this point */
489 if (session
->consumer_fd
== 0) {
490 session
->consumer_fd
= kconsumerd_cmd_sock
;
493 if (session
->metadata_stream_fd
!= 0) {
494 /* Send metadata stream fd first */
495 lkm
.fd
= session
->metadata_stream_fd
;
496 lkm
.state
= ACTIVE_FD
;
497 lkm
.max_sb_size
= session
->metadata
->conf
->attr
.subbuf_size
;
498 lkm
.output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
499 strncpy(lkm
.path_name
, session
->metadata
->pathname
, PATH_MAX
);
500 lkm
.path_name
[PATH_MAX
- 1] = '\0';
502 ret
= lttcomm_send_fds_unix_sock(session
->consumer_fd
, &lkm
, &lkm
.fd
, 1, sizeof(lkm
));
504 perror("send kconsumerd fd");
509 cds_list_for_each_entry(chan
, &session
->channel_list
.head
, list
) {
510 ret
= send_kconsumerd_channel_fds(session
->consumer_fd
, chan
);
516 DBG("Kconsumerd fds (metadata and channel streams) sent");
525 * Notify UST applications using the shm mmap futex.
527 static int notify_ust_apps(int active
)
531 DBG("Notifying applications of session daemon state: %d", active
);
533 tracepoint(ust_notify_apps_start
);
535 /* See shm.c for this call implying mmap, shm and futex calls */
536 wait_shm_mmap
= shm_ust_get_mmap(wait_shm_path
, is_root
);
537 if (wait_shm_mmap
== NULL
) {
541 /* Wake waiting process */
542 futex_wait_update((int32_t *) wait_shm_mmap
, active
);
544 tracepoint(ust_notify_apps_stop
);
546 /* Apps notified successfully */
554 * Setup the outgoing data buffer for the response (llm) by allocating the
555 * right amount of memory and copying the original information from the lsm
558 * Return total size of the buffer pointed by buf.
560 static int setup_lttng_msg(struct command_ctx
*cmd_ctx
, size_t size
)
566 cmd_ctx
->llm
= malloc(sizeof(struct lttcomm_lttng_msg
) + buf_size
);
567 if (cmd_ctx
->llm
== NULL
) {
573 /* Copy common data */
574 cmd_ctx
->llm
->cmd_type
= cmd_ctx
->lsm
->cmd_type
;
575 cmd_ctx
->llm
->pid
= cmd_ctx
->lsm
->domain
.attr
.pid
;
577 cmd_ctx
->llm
->data_size
= size
;
578 cmd_ctx
->lttng_msg_size
= sizeof(struct lttcomm_lttng_msg
) + buf_size
;
587 * Update the kernel poll set of all channel fd available over all tracing
588 * session. Add the wakeup pipe at the end of the set.
590 static int update_kernel_poll(struct lttng_poll_event
*events
)
593 struct ltt_session
*session
;
594 struct ltt_kernel_channel
*channel
;
596 DBG("Updating kernel poll set");
599 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
600 lock_session(session
);
601 if (session
->kernel_session
== NULL
) {
602 unlock_session(session
);
606 cds_list_for_each_entry(channel
, &session
->kernel_session
->channel_list
.head
, list
) {
607 /* Add channel fd to the kernel poll set */
608 ret
= lttng_poll_add(events
, channel
->fd
, LPOLLIN
| LPOLLRDNORM
);
610 unlock_session(session
);
613 DBG("Channel fd %d added to kernel set", channel
->fd
);
615 unlock_session(session
);
617 unlock_session_list();
622 unlock_session_list();
627 * Find the channel fd from 'fd' over all tracing session. When found, check
628 * for new channel stream and send those stream fds to the kernel consumer.
630 * Useful for CPU hotplug feature.
632 static int update_kernel_stream(int fd
)
635 struct ltt_session
*session
;
636 struct ltt_kernel_channel
*channel
;
638 DBG("Updating kernel streams for channel fd %d", fd
);
641 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
642 lock_session(session
);
643 if (session
->kernel_session
== NULL
) {
644 unlock_session(session
);
648 /* This is not suppose to be 0 but this is an extra security check */
649 if (session
->kernel_session
->consumer_fd
== 0) {
650 session
->kernel_session
->consumer_fd
= kconsumerd_cmd_sock
;
653 cds_list_for_each_entry(channel
,
654 &session
->kernel_session
->channel_list
.head
, list
) {
655 if (channel
->fd
== fd
) {
656 DBG("Channel found, updating kernel streams");
657 ret
= kernel_open_channel_stream(channel
);
663 * Have we already sent fds to the consumer? If yes, it means
664 * that tracing is started so it is safe to send our updated
667 if (session
->kernel_session
->kconsumer_fds_sent
== 1) {
668 ret
= send_kconsumerd_channel_fds(
669 session
->kernel_session
->consumer_fd
, channel
);
677 unlock_session(session
);
679 unlock_session_list();
683 unlock_session(session
);
684 unlock_session_list();
689 * This thread manage event coming from the kernel.
691 * Features supported in this thread:
694 static void *thread_manage_kernel(void *data
)
696 int ret
, i
, pollfd
, update_poll_flag
= 1;
697 uint32_t revents
, nb_fd
;
699 struct lttng_poll_event events
;
701 tracepoint(sessiond_th_kern_start
);
703 DBG("Thread manage kernel started");
705 ret
= create_thread_poll_set(&events
, 2);
710 ret
= lttng_poll_add(&events
, kernel_poll_pipe
[0], LPOLLIN
);
716 if (update_poll_flag
== 1) {
717 ret
= update_kernel_poll(&events
);
721 update_poll_flag
= 0;
724 nb_fd
= LTTNG_POLL_GETNB(&events
);
726 DBG("Thread kernel polling on %d fds", nb_fd
);
728 /* Zeroed the poll events */
729 lttng_poll_reset(&events
);
731 tracepoint(sessiond_th_kern_poll
);
733 /* Poll infinite value of time */
734 ret
= lttng_poll_wait(&events
, -1);
737 } else if (ret
== 0) {
738 /* Should not happen since timeout is infinite */
739 ERR("Return value of poll is 0 with an infinite timeout.\n"
740 "This should not have happened! Continuing...");
744 for (i
= 0; i
< nb_fd
; i
++) {
745 /* Fetch once the poll data */
746 revents
= LTTNG_POLL_GETEV(&events
, i
);
747 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
749 /* Thread quit pipe has been closed. Killing thread. */
750 ret
= check_thread_quit_pipe(pollfd
, revents
);
755 /* Check for data on kernel pipe */
756 if (pollfd
== kernel_poll_pipe
[0] && (revents
& LPOLLIN
)) {
757 ret
= read(kernel_poll_pipe
[0], &tmp
, 1);
758 update_poll_flag
= 1;
762 * New CPU detected by the kernel. Adding kernel stream to
763 * kernel session and updating the kernel consumer
765 if (revents
& LPOLLIN
) {
766 ret
= update_kernel_stream(pollfd
);
772 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
773 * and unregister kernel stream at this point.
781 DBG("Kernel thread dying");
782 close(kernel_poll_pipe
[0]);
783 close(kernel_poll_pipe
[1]);
785 lttng_poll_clean(&events
);
791 * This thread manage the kconsumerd error sent back to the session daemon.
793 static void *thread_manage_kconsumerd(void *data
)
795 int sock
= 0, i
, ret
, pollfd
;
796 uint32_t revents
, nb_fd
;
797 enum lttcomm_return_code code
;
798 struct lttng_poll_event events
;
800 tracepoint(sessiond_th_kcon_start
);
802 DBG("[thread] Manage kconsumerd started");
804 ret
= lttcomm_listen_unix_sock(kconsumerd_err_sock
);
810 * Pass 2 as size here for the thread quit pipe and kconsumerd_err_sock.
811 * Nothing more will be added to this poll set.
813 ret
= create_thread_poll_set(&events
, 2);
818 ret
= lttng_poll_add(&events
, kconsumerd_err_sock
, LPOLLIN
| LPOLLRDHUP
);
823 nb_fd
= LTTNG_POLL_GETNB(&events
);
825 tracepoint(sessiond_th_kcon_poll
);
827 /* Inifinite blocking call, waiting for transmission */
828 ret
= lttng_poll_wait(&events
, -1);
833 for (i
= 0; i
< nb_fd
; i
++) {
834 /* Fetch once the poll data */
835 revents
= LTTNG_POLL_GETEV(&events
, i
);
836 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
838 /* Thread quit pipe has been closed. Killing thread. */
839 ret
= check_thread_quit_pipe(pollfd
, revents
);
844 /* Event on the registration socket */
845 if (pollfd
== kconsumerd_err_sock
) {
846 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
847 ERR("Kconsumerd err socket poll error");
853 sock
= lttcomm_accept_unix_sock(kconsumerd_err_sock
);
858 /* Getting status code from kconsumerd */
859 ret
= lttcomm_recv_unix_sock(sock
, &code
, sizeof(enum lttcomm_return_code
));
864 if (code
== KCONSUMERD_COMMAND_SOCK_READY
) {
865 kconsumerd_cmd_sock
= lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path
);
866 if (kconsumerd_cmd_sock
< 0) {
867 sem_post(&kconsumerd_sem
);
868 perror("kconsumerd connect");
871 /* Signal condition to tell that the kconsumerd is ready */
872 sem_post(&kconsumerd_sem
);
873 DBG("Kconsumerd command socket ready");
875 DBG("Kconsumerd error when waiting for SOCK_READY : %s",
876 lttcomm_get_readable_code(-code
));
880 /* Remove the kconsumerd error socket since we have established a connexion */
881 ret
= lttng_poll_del(&events
, kconsumerd_err_sock
);
886 ret
= lttng_poll_add(&events
, sock
, LPOLLIN
| LPOLLRDHUP
);
891 /* Update number of fd */
892 nb_fd
= LTTNG_POLL_GETNB(&events
);
894 /* Inifinite blocking call, waiting for transmission */
895 ret
= lttng_poll_wait(&events
, -1);
900 for (i
= 0; i
< nb_fd
; i
++) {
901 /* Fetch once the poll data */
902 revents
= LTTNG_POLL_GETEV(&events
, i
);
903 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
905 /* Thread quit pipe has been closed. Killing thread. */
906 ret
= check_thread_quit_pipe(pollfd
, revents
);
911 /* Event on the kconsumerd socket */
912 if (pollfd
== sock
) {
913 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
914 ERR("Kconsumerd err socket second poll error");
920 /* Wait for any kconsumerd error */
921 ret
= lttcomm_recv_unix_sock(sock
, &code
, sizeof(enum lttcomm_return_code
));
923 ERR("Kconsumerd closed the command socket");
927 ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code
));
930 DBG("Kconsumerd thread dying");
931 close(kconsumerd_err_sock
);
932 close(kconsumerd_cmd_sock
);
935 unlink(kconsumerd_err_unix_sock_path
);
936 unlink(kconsumerd_cmd_unix_sock_path
);
939 lttng_poll_clean(&events
);
945 * This thread manage application communication.
947 static void *thread_manage_apps(void *data
)
950 uint32_t revents
, nb_fd
;
951 struct ust_command ust_cmd
;
952 struct lttng_poll_event events
;
954 tracepoint(sessiond_th_apps_start
);
956 DBG("[thread] Manage application started");
958 ret
= create_thread_poll_set(&events
, 2);
963 ret
= lttng_poll_add(&events
, apps_cmd_pipe
[0], LPOLLIN
| LPOLLRDHUP
);
969 /* Zeroed the events structure */
970 lttng_poll_reset(&events
);
972 nb_fd
= LTTNG_POLL_GETNB(&events
);
974 DBG("Apps thread polling on %d fds", nb_fd
);
976 tracepoint(sessiond_th_apps_poll
);
978 /* Inifinite blocking call, waiting for transmission */
979 ret
= lttng_poll_wait(&events
, -1);
984 for (i
= 0; i
< nb_fd
; i
++) {
985 /* Fetch once the poll data */
986 revents
= LTTNG_POLL_GETEV(&events
, i
);
987 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
989 /* Thread quit pipe has been closed. Killing thread. */
990 ret
= check_thread_quit_pipe(pollfd
, revents
);
995 /* Inspect the apps cmd pipe */
996 if (pollfd
== apps_cmd_pipe
[0]) {
997 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
998 ERR("Apps command pipe error");
1000 } else if (revents
& LPOLLIN
) {
1001 tracepoint(ust_register_read_start
);
1003 ret
= read(apps_cmd_pipe
[0], &ust_cmd
, sizeof(ust_cmd
));
1004 if (ret
< 0 || ret
< sizeof(ust_cmd
)) {
1005 perror("read apps cmd pipe");
1008 tracepoint(ust_register_read_stop
);
1010 tracepoint(ust_register_add_start
);
1011 /* Register applicaton to the session daemon */
1012 ret
= register_traceable_app(&ust_cmd
.reg_msg
, ust_cmd
.sock
);
1014 /* Only critical ENOMEM error can be returned here */
1017 tracepoint(ust_register_add_stop
);
1019 tracepoint(ust_register_done_start
);
1020 ret
= ustctl_register_done(ust_cmd
.sock
);
1023 * If the registration is not possible, we simply
1024 * unregister the apps and continue
1026 unregister_traceable_app(ust_cmd
.sock
);
1029 * We just need here to monitor the close of the UST
1030 * socket and poll set monitor those by default.
1032 ret
= lttng_poll_add(&events
, ust_cmd
.sock
, 0);
1037 DBG("Apps with sock %d added to poll set", ust_cmd
.sock
);
1039 tracepoint(ust_register_done_stop
);
1044 * At this point, we know that a registered application made the
1045 * event at poll_wait.
1047 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1048 /* Removing from the poll set */
1049 ret
= lttng_poll_del(&events
, pollfd
);
1055 unregister_traceable_app(pollfd
);
1063 DBG("Application communication apps dying");
1064 close(apps_cmd_pipe
[0]);
1065 close(apps_cmd_pipe
[1]);
1067 lttng_poll_clean(&events
);
1073 * Dispatch request from the registration threads to the application
1074 * communication thread.
1076 static void *thread_dispatch_ust_registration(void *data
)
1079 struct cds_wfq_node
*node
;
1080 struct ust_command
*ust_cmd
= NULL
;
1082 tracepoint(sessiond_th_dispatch_start
);
1084 DBG("[thread] Dispatch UST command started");
1086 while (!dispatch_thread_exit
) {
1087 /* Atomically prepare the queue futex */
1088 futex_nto1_prepare(&ust_cmd_queue
.futex
);
1091 tracepoint(sessiond_th_dispatch_block
);
1093 /* Dequeue command for registration */
1094 node
= cds_wfq_dequeue_blocking(&ust_cmd_queue
.queue
);
1096 DBG("Waked up but nothing in the UST command queue");
1097 /* Continue thread execution */
1101 tracepoint(ust_dispatch_register_start
);
1103 ust_cmd
= caa_container_of(node
, struct ust_command
, node
);
1105 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1106 " gid:%d sock:%d name:%s (version %d.%d)",
1107 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1108 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1109 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1110 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1112 * Inform apps thread of the new application registration. This
1113 * call is blocking so we can be assured that the data will be read
1114 * at some point in time or wait to the end of the world :)
1116 ret
= write(apps_cmd_pipe
[1], ust_cmd
,
1117 sizeof(struct ust_command
));
1119 perror("write apps cmd pipe");
1120 if (errno
== EBADF
) {
1122 * We can't inform the application thread to process
1123 * registration. We will exit or else application
1124 * registration will not occur and tracing will never
1131 } while (node
!= NULL
);
1133 tracepoint(ust_dispatch_register_stop
);
1135 /* Futex wait on queue. Blocking call on futex() */
1136 futex_nto1_wait(&ust_cmd_queue
.futex
);
1140 DBG("Dispatch thread dying");
1145 * This thread manage application registration.
1147 static void *thread_registration_apps(void *data
)
1149 int sock
= 0, i
, ret
, pollfd
;
1150 uint32_t revents
, nb_fd
;
1151 struct lttng_poll_event events
;
1153 * Get allocated in this thread, enqueued to a global queue, dequeued and
1154 * freed in the manage apps thread.
1156 struct ust_command
*ust_cmd
= NULL
;
1158 tracepoint(sessiond_th_reg_start
);
1160 DBG("[thread] Manage application registration started");
1162 ret
= lttcomm_listen_unix_sock(apps_sock
);
1168 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
1169 * more will be added to this poll set.
1171 ret
= create_thread_poll_set(&events
, 2);
1176 /* Add the application registration socket */
1177 ret
= lttng_poll_add(&events
, apps_sock
, LPOLLIN
| LPOLLRDHUP
);
1182 /* Notify all applications to register */
1183 ret
= notify_ust_apps(1);
1185 ERR("Failed to notify applications or create the wait shared memory.\n"
1186 "Execution continues but there might be problem for already running\n"
1187 "applications that wishes to register.");
1191 DBG("Accepting application registration");
1193 tracepoint(sessiond_th_reg_poll
);
1195 nb_fd
= LTTNG_POLL_GETNB(&events
);
1197 /* Inifinite blocking call, waiting for transmission */
1198 ret
= lttng_poll_wait(&events
, -1);
1203 for (i
= 0; i
< nb_fd
; i
++) {
1204 /* Fetch once the poll data */
1205 revents
= LTTNG_POLL_GETEV(&events
, i
);
1206 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
1208 /* Thread quit pipe has been closed. Killing thread. */
1209 ret
= check_thread_quit_pipe(pollfd
, revents
);
1214 /* Event on the registration socket */
1215 if (pollfd
== apps_sock
) {
1216 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
1217 ERR("Register apps socket poll error");
1219 } else if (revents
& LPOLLIN
) {
1220 /* Registration starts here. Recording cycles */
1221 tracepoint(ust_register_start
);
1223 sock
= lttcomm_accept_unix_sock(apps_sock
);
1228 /* Create UST registration command for enqueuing */
1229 ust_cmd
= malloc(sizeof(struct ust_command
));
1230 if (ust_cmd
== NULL
) {
1231 perror("ust command malloc");
1236 * Using message-based transmissions to ensure we don't
1237 * have to deal with partially received messages.
1239 ret
= lttcomm_recv_unix_sock(sock
, &ust_cmd
->reg_msg
,
1240 sizeof(struct ust_register_msg
));
1241 if (ret
< 0 || ret
< sizeof(struct ust_register_msg
)) {
1243 perror("lttcomm_recv_unix_sock register apps");
1245 ERR("Wrong size received on apps register");
1252 ust_cmd
->sock
= sock
;
1254 DBG("UST registration received with pid:%d ppid:%d uid:%d"
1255 " gid:%d sock:%d name:%s (version %d.%d)",
1256 ust_cmd
->reg_msg
.pid
, ust_cmd
->reg_msg
.ppid
,
1257 ust_cmd
->reg_msg
.uid
, ust_cmd
->reg_msg
.gid
,
1258 ust_cmd
->sock
, ust_cmd
->reg_msg
.name
,
1259 ust_cmd
->reg_msg
.major
, ust_cmd
->reg_msg
.minor
);
1261 * Lock free enqueue the registration request. The red pill
1262 * has been taken! This apps will be part of the *system* :)
1264 cds_wfq_enqueue(&ust_cmd_queue
.queue
, &ust_cmd
->node
);
1267 * Wake the registration queue futex. Implicit memory
1268 * barrier with the exchange in cds_wfq_enqueue.
1270 futex_nto1_wake(&ust_cmd_queue
.futex
);
1272 tracepoint(ust_register_stop
);
1279 DBG("UST Registration thread dying");
1281 /* Notify that the registration thread is gone */
1286 unlink(apps_unix_sock_path
);
1288 lttng_poll_clean(&events
);
1294 * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
1295 * exec or it will fails.
1297 static int spawn_kconsumerd_thread(void)
1301 /* Setup semaphore */
1302 sem_init(&kconsumerd_sem
, 0, 0);
1304 ret
= pthread_create(&kconsumerd_thread
, NULL
, thread_manage_kconsumerd
, (void *) NULL
);
1306 perror("pthread_create kconsumerd");
1310 /* Wait for the kconsumerd thread to be ready */
1311 sem_wait(&kconsumerd_sem
);
1313 if (kconsumerd_pid
== 0) {
1314 ERR("Kconsumerd did not start");
1321 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1326 * Join kernel consumer thread
1328 static int join_kconsumerd_thread(void)
1333 if (kconsumerd_pid
!= 0) {
1334 ret
= kill(kconsumerd_pid
, SIGTERM
);
1336 ERR("Error killing kconsumerd");
1339 return pthread_join(kconsumerd_thread
, &status
);
1346 * Fork and exec a kernel consumer daemon (kconsumerd).
1348 * Return pid if successful else -1.
1350 static pid_t
spawn_kconsumerd(void)
1354 const char *verbosity
;
1356 DBG("Spawning kconsumerd");
1363 if (opt_verbose
> 1 || opt_verbose_kconsumerd
) {
1364 verbosity
= "--verbose";
1366 verbosity
= "--quiet";
1368 execl(INSTALL_BIN_PATH
"/ltt-kconsumerd", "ltt-kconsumerd", verbosity
, NULL
);
1370 perror("kernel start consumer exec");
1373 } else if (pid
> 0) {
1377 perror("kernel start consumer fork");
1387 * Spawn the kconsumerd daemon and session daemon thread.
1389 static int start_kconsumerd(void)
1393 pthread_mutex_lock(&kconsumerd_pid_mutex
);
1394 if (kconsumerd_pid
!= 0) {
1395 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1399 ret
= spawn_kconsumerd();
1401 ERR("Spawning kconsumerd failed");
1402 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1403 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1407 /* Setting up the global kconsumerd_pid */
1408 kconsumerd_pid
= ret
;
1409 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
1411 DBG("Kconsumerd pid %d", ret
);
1413 DBG("Spawning kconsumerd thread");
1414 ret
= spawn_kconsumerd_thread();
1416 ERR("Fatal error spawning kconsumerd thread");
1428 * modprobe_kernel_modules
1430 static int modprobe_kernel_modules(void)
1435 for (i
= 0; i
< ARRAY_SIZE(kernel_modules_list
); i
++) {
1436 ret
= snprintf(modprobe
, sizeof(modprobe
),
1437 "/sbin/modprobe %s%s",
1438 kernel_modules_list
[i
].required
? "" : "--quiet ",
1439 kernel_modules_list
[i
].name
);
1441 perror("snprintf modprobe");
1444 modprobe
[sizeof(modprobe
) - 1] = '\0';
1445 ret
= system(modprobe
);
1447 ERR("Unable to launch modprobe for module %s",
1448 kernel_modules_list
[i
].name
);
1449 } else if (kernel_modules_list
[i
].required
1450 && WEXITSTATUS(ret
) != 0) {
1451 ERR("Unable to load module %s",
1452 kernel_modules_list
[i
].name
);
1454 DBG("Modprobe successfully %s",
1455 kernel_modules_list
[i
].name
);
1466 static int mount_debugfs(char *path
)
1469 char *type
= "debugfs";
1471 ret
= mkdir_recursive(path
, S_IRWXU
| S_IRWXG
, geteuid(), getegid());
1476 ret
= mount(type
, path
, type
, 0, NULL
);
1478 perror("mount debugfs");
1482 DBG("Mounted debugfs successfully at %s", path
);
1489 * Setup necessary data for kernel tracer action.
1491 static void init_kernel_tracer(void)
1494 char *proc_mounts
= "/proc/mounts";
1496 char *debugfs_path
= NULL
, *lttng_path
;
1499 /* Detect debugfs */
1500 fp
= fopen(proc_mounts
, "r");
1502 ERR("Unable to probe %s", proc_mounts
);
1506 while (fgets(line
, sizeof(line
), fp
) != NULL
) {
1507 if (strstr(line
, "debugfs") != NULL
) {
1508 /* Remove first string */
1510 /* Dup string here so we can reuse line later on */
1511 debugfs_path
= strdup(strtok(NULL
, " "));
1512 DBG("Got debugfs path : %s", debugfs_path
);
1519 /* Mount debugfs if needded */
1520 if (debugfs_path
== NULL
) {
1521 ret
= asprintf(&debugfs_path
, "/mnt/debugfs");
1523 perror("asprintf debugfs path");
1526 ret
= mount_debugfs(debugfs_path
);
1532 /* Modprobe lttng kernel modules */
1533 ret
= modprobe_kernel_modules();
1538 /* Setup lttng kernel path */
1539 ret
= asprintf(<tng_path
, "%s/lttng", debugfs_path
);
1541 perror("asprintf lttng path");
1545 /* Open debugfs lttng */
1546 kernel_tracer_fd
= open(lttng_path
, O_RDWR
);
1547 if (kernel_tracer_fd
< 0) {
1548 DBG("Failed to open %s", lttng_path
);
1554 DBG("Kernel tracer fd %d", kernel_tracer_fd
);
1564 WARN("No kernel tracer available");
1565 kernel_tracer_fd
= 0;
1570 * Start tracing by creating trace directory and sending FDs to the kernel
1573 static int start_kernel_trace(struct ltt_kernel_session
*session
)
1577 if (session
->kconsumer_fds_sent
== 0) {
1579 * Assign default kernel consumer if no consumer assigned to the kernel
1580 * session. At this point, it's NOT suppose to be 0 but this is an extra
1583 if (session
->consumer_fd
== 0) {
1584 session
->consumer_fd
= kconsumerd_cmd_sock
;
1587 ret
= send_kconsumerd_fds(session
);
1589 ERR("Send kconsumerd fds failed");
1590 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
1594 session
->kconsumer_fds_sent
= 1;
1602 * Notify kernel thread to update it's poll set.
1604 static int notify_kernel_channels_update(void)
1608 /* Inform kernel thread of the new kernel channel */
1609 ret
= write(kernel_poll_pipe
[1], "!", 1);
1611 perror("write kernel poll pipe");
1618 * Allocate a channel structure and fill it.
1620 static struct lttng_channel
*init_default_channel(enum lttng_domain_type domain_type
,
1623 struct lttng_channel
*chan
;
1625 chan
= malloc(sizeof(struct lttng_channel
));
1627 perror("init channel malloc");
1631 if (snprintf(chan
->name
, NAME_MAX
, "%s", name
) < 0) {
1632 perror("snprintf channel name");
1636 chan
->attr
.overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
1637 chan
->attr
.switch_timer_interval
= DEFAULT_CHANNEL_SWITCH_TIMER
;
1638 chan
->attr
.read_timer_interval
= DEFAULT_CHANNEL_READ_TIMER
;
1640 switch (domain_type
) {
1641 case LTTNG_DOMAIN_KERNEL
:
1642 chan
->attr
.subbuf_size
= DEFAULT_KERNEL_CHANNEL_SUBBUF_SIZE
;
1643 chan
->attr
.num_subbuf
= DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM
;
1644 chan
->attr
.output
= DEFAULT_KERNEL_CHANNEL_OUTPUT
;
1648 goto error
; /* Not implemented */
1659 * Create an UST session and add it to the session ust list.
1661 static int create_ust_session(pid_t pid
, struct ltt_session
*session
)
1664 struct ltt_ust_session
*lus
;
1666 DBG("Creating UST session");
1668 lus
= trace_ust_create_session(session
->path
, pid
);
1673 ret
= mkdir_recursive(lus
->path
, S_IRWXU
| S_IRWXG
,
1674 geteuid(), allowed_group());
1676 if (ret
!= -EEXIST
) {
1677 ERR("Trace directory creation error");
1682 /* Create session on the UST tracer */
1683 ret
= ustctl_create_session(lus
);
1696 * Create a kernel tracer session then create the default channel.
1698 static int create_kernel_session(struct ltt_session
*session
)
1702 DBG("Creating kernel session");
1704 ret
= kernel_create_session(session
, kernel_tracer_fd
);
1706 ret
= LTTCOMM_KERN_SESS_FAIL
;
1710 /* Set kernel consumer socket fd */
1711 if (kconsumerd_cmd_sock
) {
1712 session
->kernel_session
->consumer_fd
= kconsumerd_cmd_sock
;
1715 ret
= mkdir_recursive(session
->kernel_session
->trace_path
,
1716 S_IRWXU
| S_IRWXG
, geteuid(), allowed_group());
1718 if (ret
!= -EEXIST
) {
1719 ERR("Trace directory creation error");
1729 * Using the session list, filled a lttng_session array to send back to the
1730 * client for session listing.
1732 * The session list lock MUST be acquired before calling this function. Use
1733 * lock_session_list() and unlock_session_list().
1735 static void list_lttng_sessions(struct lttng_session
*sessions
)
1738 struct ltt_session
*session
;
1740 DBG("Getting all available session");
1742 * Iterate over session list and append data after the control struct in
1745 cds_list_for_each_entry(session
, &session_list_ptr
->head
, list
) {
1746 strncpy(sessions
[i
].path
, session
->path
, PATH_MAX
);
1747 sessions
[i
].path
[PATH_MAX
- 1] = '\0';
1748 strncpy(sessions
[i
].name
, session
->name
, NAME_MAX
);
1749 sessions
[i
].name
[NAME_MAX
- 1] = '\0';
1755 * Fill lttng_channel array of all channels.
1757 static void list_lttng_channels(struct ltt_session
*session
,
1758 struct lttng_channel
*channels
)
1761 struct ltt_kernel_channel
*kchan
;
1763 DBG("Listing channels for session %s", session
->name
);
1765 /* Kernel channels */
1766 if (session
->kernel_session
!= NULL
) {
1767 cds_list_for_each_entry(kchan
, &session
->kernel_session
->channel_list
.head
, list
) {
1768 /* Copy lttng_channel struct to array */
1769 memcpy(&channels
[i
], kchan
->channel
, sizeof(struct lttng_channel
));
1770 channels
[i
].enabled
= kchan
->enabled
;
1775 /* TODO: Missing UST listing */
1779 * Fill lttng_event array of all events in the channel.
1781 static void list_lttng_events(struct ltt_kernel_channel
*kchan
,
1782 struct lttng_event
*events
)
1785 * TODO: This is ONLY kernel. Need UST support.
1788 struct ltt_kernel_event
*event
;
1790 DBG("Listing events for channel %s", kchan
->channel
->name
);
1792 /* Kernel channels */
1793 cds_list_for_each_entry(event
, &kchan
->events_list
.head
, list
) {
1794 strncpy(events
[i
].name
, event
->event
->name
, LTTNG_SYMBOL_NAME_LEN
);
1795 events
[i
].name
[LTTNG_SYMBOL_NAME_LEN
- 1] = '\0';
1796 events
[i
].enabled
= event
->enabled
;
1797 switch (event
->event
->instrumentation
) {
1798 case LTTNG_KERNEL_TRACEPOINT
:
1799 events
[i
].type
= LTTNG_EVENT_TRACEPOINT
;
1801 case LTTNG_KERNEL_KPROBE
:
1802 case LTTNG_KERNEL_KRETPROBE
:
1803 events
[i
].type
= LTTNG_EVENT_PROBE
;
1804 memcpy(&events
[i
].attr
.probe
, &event
->event
->u
.kprobe
,
1805 sizeof(struct lttng_kernel_kprobe
));
1807 case LTTNG_KERNEL_FUNCTION
:
1808 events
[i
].type
= LTTNG_EVENT_FUNCTION
;
1809 memcpy(&events
[i
].attr
.ftrace
, &event
->event
->u
.ftrace
,
1810 sizeof(struct lttng_kernel_function
));
1818 * Process the command requested by the lttng client within the command
1819 * context structure. This function make sure that the return structure (llm)
1820 * is set and ready for transmission before returning.
1822 * Return any error encountered or 0 for success.
1824 static int process_client_msg(struct command_ctx
*cmd_ctx
)
1826 int ret
= LTTCOMM_OK
;
1828 DBG("Processing client command %d", cmd_ctx
->lsm
->cmd_type
);
1831 * Commands that DO NOT need a session.
1833 switch (cmd_ctx
->lsm
->cmd_type
) {
1834 case LTTNG_CREATE_SESSION
:
1835 case LTTNG_LIST_SESSIONS
:
1836 case LTTNG_LIST_TRACEPOINTS
:
1837 case LTTNG_CALIBRATE
:
1840 DBG("Getting session %s by name", cmd_ctx
->lsm
->session
.name
);
1841 cmd_ctx
->session
= find_session_by_name(cmd_ctx
->lsm
->session
.name
);
1842 if (cmd_ctx
->session
== NULL
) {
1843 /* If session name not found */
1844 if (cmd_ctx
->lsm
->session
.name
!= NULL
) {
1845 ret
= LTTCOMM_SESS_NOT_FOUND
;
1846 } else { /* If no session name specified */
1847 ret
= LTTCOMM_SELECT_SESS
;
1851 /* Acquire lock for the session */
1852 lock_session(cmd_ctx
->session
);
1858 * Check domain type for specific "pre-action".
1860 switch (cmd_ctx
->lsm
->domain
.type
) {
1861 case LTTNG_DOMAIN_KERNEL
:
1862 /* Kernel tracer check */
1863 if (kernel_tracer_fd
== 0) {
1864 init_kernel_tracer();
1865 if (kernel_tracer_fd
== 0) {
1866 ret
= LTTCOMM_KERN_NA
;
1870 /* Need a session for kernel command */
1871 switch (cmd_ctx
->lsm
->cmd_type
) {
1872 case LTTNG_CALIBRATE
:
1873 case LTTNG_CREATE_SESSION
:
1874 case LTTNG_LIST_SESSIONS
:
1875 case LTTNG_LIST_TRACEPOINTS
:
1878 if (cmd_ctx
->session
->kernel_session
== NULL
) {
1879 ret
= create_kernel_session(cmd_ctx
->session
);
1881 ret
= LTTCOMM_KERN_SESS_FAIL
;
1884 /* Start the kernel consumer daemon */
1885 if (kconsumerd_pid
== 0 &&
1886 cmd_ctx
->lsm
->cmd_type
!= LTTNG_REGISTER_CONSUMER
) {
1887 ret
= start_kconsumerd();
1895 case LTTNG_DOMAIN_UST_PID
:
1901 /* Process by command type */
1902 switch (cmd_ctx
->lsm
->cmd_type
) {
1903 case LTTNG_ADD_CONTEXT
:
1905 struct lttng_kernel_context kctx
;
1907 /* Setup lttng message with no payload */
1908 ret
= setup_lttng_msg(cmd_ctx
, 0);
1913 switch (cmd_ctx
->lsm
->domain
.type
) {
1914 case LTTNG_DOMAIN_KERNEL
:
1915 /* Create Kernel context */
1916 kctx
.ctx
= cmd_ctx
->lsm
->u
.context
.ctx
.ctx
;
1917 kctx
.u
.perf_counter
.type
= cmd_ctx
->lsm
->u
.context
.ctx
.u
.perf_counter
.type
;
1918 kctx
.u
.perf_counter
.config
= cmd_ctx
->lsm
->u
.context
.ctx
.u
.perf_counter
.config
;
1919 strncpy(kctx
.u
.perf_counter
.name
,
1920 cmd_ctx
->lsm
->u
.context
.ctx
.u
.perf_counter
.name
,
1921 LTTNG_SYMBOL_NAME_LEN
);
1922 kctx
.u
.perf_counter
.name
[LTTNG_SYMBOL_NAME_LEN
- 1] = '\0';
1924 /* Add kernel context to kernel tracer. See context.c */
1925 ret
= add_kernel_context(cmd_ctx
->session
->kernel_session
, &kctx
,
1926 cmd_ctx
->lsm
->u
.context
.event_name
,
1927 cmd_ctx
->lsm
->u
.context
.channel_name
);
1928 if (ret
!= LTTCOMM_OK
) {
1933 /* TODO: Userspace tracing */
1934 ret
= LTTCOMM_NOT_IMPLEMENTED
;
1941 case LTTNG_DISABLE_CHANNEL
:
1943 struct ltt_kernel_channel
*kchan
;
1945 /* Setup lttng message with no payload */
1946 ret
= setup_lttng_msg(cmd_ctx
, 0);
1951 switch (cmd_ctx
->lsm
->domain
.type
) {
1952 case LTTNG_DOMAIN_KERNEL
:
1953 kchan
= trace_kernel_get_channel_by_name(cmd_ctx
->lsm
->u
.disable
.channel_name
,
1954 cmd_ctx
->session
->kernel_session
);
1955 if (kchan
== NULL
) {
1956 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
1958 } else if (kchan
->enabled
== 1) {
1959 ret
= kernel_disable_channel(kchan
);
1961 if (ret
!= EEXIST
) {
1962 ret
= LTTCOMM_KERN_CHAN_DISABLE_FAIL
;
1967 kernel_wait_quiescent(kernel_tracer_fd
);
1970 /* TODO: Userspace tracing */
1971 ret
= LTTCOMM_NOT_IMPLEMENTED
;
1978 case LTTNG_DISABLE_EVENT
:
1980 struct ltt_kernel_channel
*kchan
;
1981 struct ltt_kernel_event
*kevent
;
1983 /* Setup lttng message with no payload */
1984 ret
= setup_lttng_msg(cmd_ctx
, 0);
1989 switch (cmd_ctx
->lsm
->domain
.type
) {
1990 case LTTNG_DOMAIN_KERNEL
:
1991 kchan
= trace_kernel_get_channel_by_name(cmd_ctx
->lsm
->u
.disable
.channel_name
,
1992 cmd_ctx
->session
->kernel_session
);
1993 if (kchan
== NULL
) {
1994 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
1998 kevent
= trace_kernel_get_event_by_name(cmd_ctx
->lsm
->u
.disable
.name
, kchan
);
1999 if (kevent
!= NULL
) {
2000 DBG("Disabling kernel event %s for channel %s.", kevent
->event
->name
,
2001 kchan
->channel
->name
);
2002 ret
= kernel_disable_event(kevent
);
2004 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
2009 kernel_wait_quiescent(kernel_tracer_fd
);
2012 /* TODO: Userspace tracing */
2013 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2020 case LTTNG_DISABLE_ALL_EVENT
:
2022 struct ltt_kernel_channel
*kchan
;
2023 struct ltt_kernel_event
*kevent
;
2025 /* Setup lttng message with no payload */
2026 ret
= setup_lttng_msg(cmd_ctx
, 0);
2031 switch (cmd_ctx
->lsm
->domain
.type
) {
2032 case LTTNG_DOMAIN_KERNEL
:
2033 DBG("Disabling all enabled kernel events");
2034 kchan
= trace_kernel_get_channel_by_name(cmd_ctx
->lsm
->u
.disable
.channel_name
,
2035 cmd_ctx
->session
->kernel_session
);
2036 if (kchan
== NULL
) {
2037 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
2041 /* For each event in the kernel session */
2042 cds_list_for_each_entry(kevent
, &kchan
->events_list
.head
, list
) {
2043 DBG("Disabling kernel event %s for channel %s.",
2044 kevent
->event
->name
, kchan
->channel
->name
);
2045 ret
= kernel_disable_event(kevent
);
2051 /* Quiescent wait after event disable */
2052 kernel_wait_quiescent(kernel_tracer_fd
);
2055 /* TODO: Userspace tracing */
2056 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2063 case LTTNG_ENABLE_CHANNEL
:
2065 struct ltt_kernel_channel
*kchan
;
2067 /* Setup lttng message with no payload */
2068 ret
= setup_lttng_msg(cmd_ctx
, 0);
2073 switch (cmd_ctx
->lsm
->domain
.type
) {
2074 case LTTNG_DOMAIN_KERNEL
:
2075 kchan
= trace_kernel_get_channel_by_name(
2076 cmd_ctx
->lsm
->u
.enable
.channel_name
,
2077 cmd_ctx
->session
->kernel_session
);
2078 if (kchan
== NULL
) {
2079 /* Channel not found, creating it */
2080 DBG("Creating kernel channel %s",
2081 cmd_ctx
->lsm
->u
.enable
.channel_name
);
2083 ret
= kernel_create_channel(cmd_ctx
->session
->kernel_session
,
2084 &cmd_ctx
->lsm
->u
.channel
.chan
,
2085 cmd_ctx
->session
->kernel_session
->trace_path
);
2087 ret
= LTTCOMM_KERN_CHAN_FAIL
;
2091 /* Notify kernel thread that there is a new channel */
2092 ret
= notify_kernel_channels_update();
2094 ret
= LTTCOMM_FATAL
;
2097 } else if (kchan
->enabled
== 0) {
2098 ret
= kernel_enable_channel(kchan
);
2100 if (ret
!= EEXIST
) {
2101 ret
= LTTCOMM_KERN_CHAN_ENABLE_FAIL
;
2107 kernel_wait_quiescent(kernel_tracer_fd
);
2109 case LTTNG_DOMAIN_UST_PID
:
2113 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2120 case LTTNG_ENABLE_EVENT
:
2123 struct ltt_kernel_channel
*kchan
;
2124 struct ltt_kernel_event
*kevent
;
2125 struct lttng_channel
*chan
;
2127 /* Setup lttng message with no payload */
2128 ret
= setup_lttng_msg(cmd_ctx
, 0);
2133 channel_name
= cmd_ctx
->lsm
->u
.enable
.channel_name
;
2135 switch (cmd_ctx
->lsm
->domain
.type
) {
2136 case LTTNG_DOMAIN_KERNEL
:
2137 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2138 cmd_ctx
->session
->kernel_session
);
2139 if (kchan
== NULL
) {
2140 DBG("Channel not found. Creating channel %s", channel_name
);
2142 chan
= init_default_channel(cmd_ctx
->lsm
->domain
.type
, channel_name
);
2144 ret
= LTTCOMM_FATAL
;
2148 ret
= kernel_create_channel(cmd_ctx
->session
->kernel_session
,
2149 chan
, cmd_ctx
->session
->kernel_session
->trace_path
);
2151 ret
= LTTCOMM_KERN_CHAN_FAIL
;
2154 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2155 cmd_ctx
->session
->kernel_session
);
2156 if (kchan
== NULL
) {
2157 ERR("Channel %s not found after creation. Internal error, giving up.",
2159 ret
= LTTCOMM_FATAL
;
2163 ret
= notify_kernel_channels_update();
2165 ret
= LTTCOMM_FATAL
;
2170 kevent
= trace_kernel_get_event_by_name(cmd_ctx
->lsm
->u
.enable
.event
.name
, kchan
);
2171 if (kevent
== NULL
) {
2172 DBG("Creating kernel event %s for channel %s.",
2173 cmd_ctx
->lsm
->u
.enable
.event
.name
, channel_name
);
2174 ret
= kernel_create_event(&cmd_ctx
->lsm
->u
.enable
.event
, kchan
);
2176 DBG("Enabling kernel event %s for channel %s.",
2177 kevent
->event
->name
, channel_name
);
2178 ret
= kernel_enable_event(kevent
);
2179 if (ret
== -EEXIST
) {
2180 ret
= LTTCOMM_KERN_EVENT_EXIST
;
2186 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
2190 kernel_wait_quiescent(kernel_tracer_fd
);
2193 /* TODO: Userspace tracing */
2194 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2200 case LTTNG_ENABLE_ALL_EVENT
:
2204 struct ltt_kernel_channel
*kchan
;
2205 struct ltt_kernel_event
*kevent
;
2206 struct lttng_event
*event_list
;
2207 struct lttng_channel
*chan
;
2209 /* Setup lttng message with no payload */
2210 ret
= setup_lttng_msg(cmd_ctx
, 0);
2215 DBG("Enabling all kernel event");
2217 channel_name
= cmd_ctx
->lsm
->u
.enable
.channel_name
;
2219 switch (cmd_ctx
->lsm
->domain
.type
) {
2220 case LTTNG_DOMAIN_KERNEL
:
2221 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2222 cmd_ctx
->session
->kernel_session
);
2223 if (kchan
== NULL
) {
2224 DBG("Channel not found. Creating channel %s", channel_name
);
2226 chan
= init_default_channel(cmd_ctx
->lsm
->domain
.type
, channel_name
);
2228 ret
= LTTCOMM_FATAL
;
2232 ret
= kernel_create_channel(cmd_ctx
->session
->kernel_session
,
2233 chan
, cmd_ctx
->session
->kernel_session
->trace_path
);
2235 ret
= LTTCOMM_KERN_CHAN_FAIL
;
2238 kchan
= trace_kernel_get_channel_by_name(channel_name
,
2239 cmd_ctx
->session
->kernel_session
);
2240 if (kchan
== NULL
) {
2241 ERR("Channel %s not found after creation. Internal error, giving up.",
2243 ret
= LTTCOMM_FATAL
;
2247 ret
= notify_kernel_channels_update();
2249 ret
= LTTCOMM_FATAL
;
2254 /* For each event in the kernel session */
2255 cds_list_for_each_entry(kevent
, &kchan
->events_list
.head
, list
) {
2256 DBG("Enabling kernel event %s for channel %s.",
2257 kevent
->event
->name
, channel_name
);
2258 ret
= kernel_enable_event(kevent
);
2264 size
= kernel_list_events(kernel_tracer_fd
, &event_list
);
2266 ret
= LTTCOMM_KERN_LIST_FAIL
;
2270 for (i
= 0; i
< size
; i
++) {
2271 kevent
= trace_kernel_get_event_by_name(event_list
[i
].name
, kchan
);
2272 if (kevent
== NULL
) {
2273 /* Default event type for enable all */
2274 event_list
[i
].type
= LTTNG_EVENT_TRACEPOINT
;
2275 /* Enable each single tracepoint event */
2276 ret
= kernel_create_event(&event_list
[i
], kchan
);
2278 /* Ignore error here and continue */
2285 /* Quiescent wait after event enable */
2286 kernel_wait_quiescent(kernel_tracer_fd
);
2289 /* TODO: Userspace tracing */
2290 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2297 case LTTNG_LIST_TRACEPOINTS
:
2299 struct lttng_event
*events
;
2300 ssize_t nb_events
= 0;
2302 switch (cmd_ctx
->lsm
->domain
.type
) {
2303 case LTTNG_DOMAIN_KERNEL
:
2304 DBG("Listing kernel events");
2305 nb_events
= kernel_list_events(kernel_tracer_fd
, &events
);
2306 if (nb_events
< 0) {
2307 ret
= LTTCOMM_KERN_LIST_FAIL
;
2312 /* TODO: Userspace listing */
2313 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2318 * Setup lttng message with payload size set to the event list size in
2319 * bytes and then copy list into the llm payload.
2321 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_event
) * nb_events
);
2327 /* Copy event list into message payload */
2328 memcpy(cmd_ctx
->llm
->payload
, events
,
2329 sizeof(struct lttng_event
) * nb_events
);
2336 case LTTNG_START_TRACE
:
2338 struct ltt_kernel_channel
*chan
;
2340 /* Setup lttng message with no payload */
2341 ret
= setup_lttng_msg(cmd_ctx
, 0);
2346 /* Kernel tracing */
2347 if (cmd_ctx
->session
->kernel_session
!= NULL
) {
2348 if (cmd_ctx
->session
->kernel_session
->metadata
== NULL
) {
2349 DBG("Open kernel metadata");
2350 ret
= kernel_open_metadata(cmd_ctx
->session
->kernel_session
,
2351 cmd_ctx
->session
->kernel_session
->trace_path
);
2353 ret
= LTTCOMM_KERN_META_FAIL
;
2358 if (cmd_ctx
->session
->kernel_session
->metadata_stream_fd
== 0) {
2359 DBG("Opening kernel metadata stream");
2360 if (cmd_ctx
->session
->kernel_session
->metadata_stream_fd
== 0) {
2361 ret
= kernel_open_metadata_stream(cmd_ctx
->session
->kernel_session
);
2363 ERR("Kernel create metadata stream failed");
2364 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2370 /* For each channel */
2371 cds_list_for_each_entry(chan
,
2372 &cmd_ctx
->session
->kernel_session
->channel_list
.head
, list
) {
2373 if (chan
->stream_count
== 0) {
2374 ret
= kernel_open_channel_stream(chan
);
2376 ERR("Kernel create channel stream failed");
2377 ret
= LTTCOMM_KERN_STREAM_FAIL
;
2380 /* Update the stream global counter */
2381 cmd_ctx
->session
->kernel_session
->stream_count_global
+= ret
;
2385 ret
= start_kernel_trace(cmd_ctx
->session
->kernel_session
);
2387 ret
= LTTCOMM_KERN_START_FAIL
;
2391 DBG("Start kernel tracing");
2392 ret
= kernel_start_session(cmd_ctx
->session
->kernel_session
);
2394 ERR("Kernel start session failed");
2395 ret
= LTTCOMM_KERN_START_FAIL
;
2399 /* Quiescent wait after starting trace */
2400 kernel_wait_quiescent(kernel_tracer_fd
);
2403 /* TODO: Start all UST traces */
2408 case LTTNG_STOP_TRACE
:
2410 struct ltt_kernel_channel
*chan
;
2411 /* Setup lttng message with no payload */
2412 ret
= setup_lttng_msg(cmd_ctx
, 0);
2418 if (cmd_ctx
->session
->kernel_session
!= NULL
) {
2419 DBG("Stop kernel tracing");
2421 ret
= kernel_metadata_flush_buffer(cmd_ctx
->session
->kernel_session
->metadata_stream_fd
);
2423 ERR("Kernel metadata flush failed");
2426 cds_list_for_each_entry(chan
, &cmd_ctx
->session
->kernel_session
->channel_list
.head
, list
) {
2427 ret
= kernel_flush_buffer(chan
);
2429 ERR("Kernel flush buffer error");
2433 ret
= kernel_stop_session(cmd_ctx
->session
->kernel_session
);
2435 ERR("Kernel stop session failed");
2436 ret
= LTTCOMM_KERN_STOP_FAIL
;
2440 /* Quiescent wait after stopping trace */
2441 kernel_wait_quiescent(kernel_tracer_fd
);
2444 /* TODO : User-space tracer */
2449 case LTTNG_CREATE_SESSION
:
2451 /* Setup lttng message with no payload */
2452 ret
= setup_lttng_msg(cmd_ctx
, 0);
2457 tracepoint(create_session_start
);
2458 ret
= create_session(cmd_ctx
->lsm
->session
.name
, cmd_ctx
->lsm
->session
.path
);
2459 tracepoint(create_session_end
);
2461 if (ret
== -EEXIST
) {
2462 ret
= LTTCOMM_EXIST_SESS
;
2464 ret
= LTTCOMM_FATAL
;
2472 case LTTNG_DESTROY_SESSION
:
2474 /* Setup lttng message with no payload */
2475 ret
= setup_lttng_msg(cmd_ctx
, 0);
2480 /* Clean kernel session teardown */
2481 teardown_kernel_session(cmd_ctx
->session
);
2483 tracepoint(destroy_session_start
);
2484 ret
= destroy_session(cmd_ctx
->lsm
->session
.name
);
2485 tracepoint(destroy_session_end
);
2487 ret
= LTTCOMM_FATAL
;
2492 * Must notify the kernel thread here to update it's poll setin order
2493 * to remove the channel(s)' fd just destroyed.
2495 ret
= notify_kernel_channels_update();
2497 ret
= LTTCOMM_FATAL
;
2504 case LTTNG_LIST_DOMAINS
:
2508 if (cmd_ctx
->session
->kernel_session
!= NULL
) {
2512 nb_dom
+= cmd_ctx
->session
->ust_session_list
.count
;
2514 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_domain
) * nb_dom
);
2519 ((struct lttng_domain
*)(cmd_ctx
->llm
->payload
))[0].type
=
2520 LTTNG_DOMAIN_KERNEL
;
2522 /* TODO: User-space tracer domain support */
2526 case LTTNG_LIST_CHANNELS
:
2529 * TODO: Only kernel channels are listed here. UST listing
2530 * is needed on lttng-ust 2.0 release.
2533 if (cmd_ctx
->session
->kernel_session
!= NULL
) {
2534 nb_chan
+= cmd_ctx
->session
->kernel_session
->channel_count
;
2537 ret
= setup_lttng_msg(cmd_ctx
,
2538 sizeof(struct lttng_channel
) * nb_chan
);
2543 list_lttng_channels(cmd_ctx
->session
,
2544 (struct lttng_channel
*)(cmd_ctx
->llm
->payload
));
2549 case LTTNG_LIST_EVENTS
:
2552 * TODO: Only kernel events are listed here. UST listing
2553 * is needed on lttng-ust 2.0 release.
2555 size_t nb_event
= 0;
2556 struct ltt_kernel_channel
*kchan
= NULL
;
2558 if (cmd_ctx
->session
->kernel_session
!= NULL
) {
2559 kchan
= trace_kernel_get_channel_by_name(cmd_ctx
->lsm
->u
.list
.channel_name
,
2560 cmd_ctx
->session
->kernel_session
);
2561 if (kchan
== NULL
) {
2562 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
2565 nb_event
+= kchan
->event_count
;
2568 ret
= setup_lttng_msg(cmd_ctx
,
2569 sizeof(struct lttng_event
) * nb_event
);
2574 DBG("Listing events (%zu events)", nb_event
);
2576 list_lttng_events(kchan
,
2577 (struct lttng_event
*)(cmd_ctx
->llm
->payload
));
2582 case LTTNG_LIST_SESSIONS
:
2584 lock_session_list();
2586 if (session_list_ptr
->count
== 0) {
2587 ret
= LTTCOMM_NO_SESSION
;
2588 unlock_session_list();
2592 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_session
) *
2593 session_list_ptr
->count
);
2595 unlock_session_list();
2599 /* Filled the session array */
2600 list_lttng_sessions((struct lttng_session
*)(cmd_ctx
->llm
->payload
));
2602 unlock_session_list();
2607 case LTTNG_CALIBRATE
:
2609 /* Setup lttng message with no payload */
2610 ret
= setup_lttng_msg(cmd_ctx
, 0);
2615 switch (cmd_ctx
->lsm
->domain
.type
) {
2616 case LTTNG_DOMAIN_KERNEL
:
2618 struct lttng_kernel_calibrate kcalibrate
;
2620 kcalibrate
.type
= cmd_ctx
->lsm
->u
.calibrate
.type
;
2621 ret
= kernel_calibrate(kernel_tracer_fd
, &kcalibrate
);
2623 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
2629 /* TODO: Userspace tracing */
2630 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2636 case LTTNG_REGISTER_CONSUMER
:
2640 /* Setup lttng message with no payload */
2641 ret
= setup_lttng_msg(cmd_ctx
, 0);
2646 switch (cmd_ctx
->lsm
->domain
.type
) {
2647 case LTTNG_DOMAIN_KERNEL
:
2649 /* Can't register a consumer if there is already one */
2650 if (cmd_ctx
->session
->kernel_session
->consumer_fd
!= 0) {
2651 ret
= LTTCOMM_CONNECT_FAIL
;
2655 sock
= lttcomm_connect_unix_sock(cmd_ctx
->lsm
->u
.reg
.path
);
2657 ret
= LTTCOMM_CONNECT_FAIL
;
2661 cmd_ctx
->session
->kernel_session
->consumer_fd
= sock
;
2665 /* TODO: Userspace tracing */
2666 ret
= LTTCOMM_NOT_IMPLEMENTED
;
2675 /* Undefined command */
2676 ret
= setup_lttng_msg(cmd_ctx
, 0);
2685 /* Set return code */
2686 cmd_ctx
->llm
->ret_code
= ret
;
2688 if (cmd_ctx
->session
) {
2689 unlock_session(cmd_ctx
->session
);
2695 if (cmd_ctx
->llm
== NULL
) {
2696 DBG("Missing llm structure. Allocating one.");
2697 if (setup_lttng_msg(cmd_ctx
, 0) < 0) {
2701 /* Notify client of error */
2702 cmd_ctx
->llm
->ret_code
= ret
;
2705 if (cmd_ctx
->session
) {
2706 unlock_session(cmd_ctx
->session
);
2712 * This thread manage all clients request using the unix client socket for
2715 static void *thread_manage_clients(void *data
)
2717 int sock
= 0, ret
, i
, pollfd
;
2718 uint32_t revents
, nb_fd
;
2719 struct command_ctx
*cmd_ctx
= NULL
;
2720 struct lttng_poll_event events
;
2722 tracepoint(sessiond_th_cli_start
);
2724 DBG("[thread] Manage client started");
2726 ret
= lttcomm_listen_unix_sock(client_sock
);
2732 * Pass 2 as size here for the thread quit pipe and client_sock. Nothing
2733 * more will be added to this poll set.
2735 ret
= create_thread_poll_set(&events
, 2);
2740 /* Add the application registration socket */
2741 ret
= lttng_poll_add(&events
, client_sock
, LPOLLIN
| LPOLLPRI
);
2747 * Notify parent pid that we are ready to accept command for client side.
2749 if (opt_sig_parent
) {
2750 kill(ppid
, SIGCHLD
);
2754 DBG("Accepting client command ...");
2756 tracepoint(sessiond_th_cli_poll
);
2758 nb_fd
= LTTNG_POLL_GETNB(&events
);
2760 /* Inifinite blocking call, waiting for transmission */
2761 ret
= lttng_poll_wait(&events
, -1);
2766 for (i
= 0; i
< nb_fd
; i
++) {
2767 /* Fetch once the poll data */
2768 revents
= LTTNG_POLL_GETEV(&events
, i
);
2769 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
2771 /* Thread quit pipe has been closed. Killing thread. */
2772 ret
= check_thread_quit_pipe(pollfd
, revents
);
2777 /* Event on the registration socket */
2778 if (pollfd
== client_sock
) {
2779 if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
2780 ERR("Client socket poll error");
2786 DBG("Wait for client response");
2788 sock
= lttcomm_accept_unix_sock(client_sock
);
2793 /* Allocate context command to process the client request */
2794 cmd_ctx
= malloc(sizeof(struct command_ctx
));
2795 if (cmd_ctx
== NULL
) {
2796 perror("malloc cmd_ctx");
2800 /* Allocate data buffer for reception */
2801 cmd_ctx
->lsm
= malloc(sizeof(struct lttcomm_session_msg
));
2802 if (cmd_ctx
->lsm
== NULL
) {
2803 perror("malloc cmd_ctx->lsm");
2807 cmd_ctx
->llm
= NULL
;
2808 cmd_ctx
->session
= NULL
;
2811 * Data is received from the lttng client. The struct
2812 * lttcomm_session_msg (lsm) contains the command and data request of
2815 DBG("Receiving data from client ...");
2816 ret
= lttcomm_recv_unix_sock(sock
, cmd_ctx
->lsm
,
2817 sizeof(struct lttcomm_session_msg
));
2819 DBG("Nothing recv() from client... continuing");
2825 // TODO: Validate cmd_ctx including sanity check for
2826 // security purpose.
2829 * This function dispatch the work to the kernel or userspace tracer
2830 * libs and fill the lttcomm_lttng_msg data structure of all the needed
2831 * informations for the client. The command context struct contains
2832 * everything this function may needs.
2834 ret
= process_client_msg(cmd_ctx
);
2837 * TODO: Inform client somehow of the fatal error. At
2838 * this point, ret < 0 means that a malloc failed
2839 * (ENOMEM). Error detected but still accept command.
2841 clean_command_ctx(&cmd_ctx
);
2845 DBG("Sending response (size: %d, retcode: %d)",
2846 cmd_ctx
->lttng_msg_size
, cmd_ctx
->llm
->ret_code
);
2847 ret
= send_unix_sock(sock
, cmd_ctx
->llm
,
2848 cmd_ctx
->lttng_msg_size
);
2850 ERR("Failed to send data back to client");
2853 clean_command_ctx(&cmd_ctx
);
2855 /* End of transmission */
2860 DBG("Client thread dying");
2861 unlink(client_unix_sock_path
);
2865 lttng_poll_clean(&events
);
2866 clean_command_ctx(&cmd_ctx
);
2872 * usage function on stderr
2874 static void usage(void)
2876 fprintf(stderr
, "Usage: %s OPTIONS\n\nOptions:\n", progname
);
2877 fprintf(stderr
, " -h, --help Display this usage.\n");
2878 fprintf(stderr
, " -c, --client-sock PATH Specify path for the client unix socket\n");
2879 fprintf(stderr
, " -a, --apps-sock PATH Specify path for apps unix socket\n");
2880 fprintf(stderr
, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
2881 fprintf(stderr
, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
2882 fprintf(stderr
, " -d, --daemonize Start as a daemon.\n");
2883 fprintf(stderr
, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
2884 fprintf(stderr
, " -V, --version Show version number.\n");
2885 fprintf(stderr
, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
2886 fprintf(stderr
, " -q, --quiet No output at all.\n");
2887 fprintf(stderr
, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
2888 fprintf(stderr
, " --verbose-kconsumerd Verbose mode for kconsumerd. Activate DBG() macro.\n");
2892 * daemon argument parsing
2894 static int parse_args(int argc
, char **argv
)
2898 static struct option long_options
[] = {
2899 { "client-sock", 1, 0, 'c' },
2900 { "apps-sock", 1, 0, 'a' },
2901 { "kconsumerd-cmd-sock", 1, 0, 0 },
2902 { "kconsumerd-err-sock", 1, 0, 0 },
2903 { "daemonize", 0, 0, 'd' },
2904 { "sig-parent", 0, 0, 'S' },
2905 { "help", 0, 0, 'h' },
2906 { "group", 1, 0, 'g' },
2907 { "version", 0, 0, 'V' },
2908 { "quiet", 0, 0, 'q' },
2909 { "verbose", 0, 0, 'v' },
2910 { "verbose-kconsumerd", 0, 0, 'Z' },
2915 int option_index
= 0;
2916 c
= getopt_long(argc
, argv
, "dhqvVS" "a:c:g:s:E:C:Z", long_options
, &option_index
);
2923 fprintf(stderr
, "option %s", long_options
[option_index
].name
);
2925 fprintf(stderr
, " with arg %s\n", optarg
);
2929 snprintf(client_unix_sock_path
, PATH_MAX
, "%s", optarg
);
2932 snprintf(apps_unix_sock_path
, PATH_MAX
, "%s", optarg
);
2938 opt_tracing_group
= strdup(optarg
);
2944 fprintf(stdout
, "%s\n", VERSION
);
2950 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
, "%s", optarg
);
2953 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
, "%s", optarg
);
2959 /* Verbose level can increase using multiple -v */
2963 opt_verbose_kconsumerd
+= 1;
2966 /* Unknown option or other error.
2967 * Error is printed by getopt, just return */
2976 * Creates the two needed socket by the daemon.
2977 * apps_sock - The communication socket for all UST apps.
2978 * client_sock - The communication of the cli tool (lttng).
2980 static int init_daemon_socket(void)
2985 old_umask
= umask(0);
2987 /* Create client tool unix socket */
2988 client_sock
= lttcomm_create_unix_sock(client_unix_sock_path
);
2989 if (client_sock
< 0) {
2990 ERR("Create unix sock failed: %s", client_unix_sock_path
);
2995 /* File permission MUST be 660 */
2996 ret
= chmod(client_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
2998 ERR("Set file permissions failed: %s", client_unix_sock_path
);
3003 /* Create the application unix socket */
3004 apps_sock
= lttcomm_create_unix_sock(apps_unix_sock_path
);
3005 if (apps_sock
< 0) {
3006 ERR("Create unix sock failed: %s", apps_unix_sock_path
);
3011 /* File permission MUST be 666 */
3012 ret
= chmod(apps_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
| S_IROTH
| S_IWOTH
);
3014 ERR("Set file permissions failed: %s", apps_unix_sock_path
);
3025 * Check if the global socket is available, and if a daemon is answering
3026 * at the other side. If yes, error is returned.
3028 static int check_existing_daemon(void)
3030 if (access(client_unix_sock_path
, F_OK
) < 0 &&
3031 access(apps_unix_sock_path
, F_OK
) < 0) {
3034 /* Is there anybody out there ? */
3035 if (lttng_session_daemon_alive()) {
3043 * Set the tracing group gid onto the client socket.
3045 * Race window between mkdir and chown is OK because we are going from more
3046 * permissive (root.root) to les permissive (root.tracing).
3048 static int set_permissions(void)
3053 gid
= allowed_group();
3056 WARN("No tracing group detected");
3059 ERR("Missing tracing group. Aborting execution.");
3065 /* Set lttng run dir */
3066 ret
= chown(LTTNG_RUNDIR
, 0, gid
);
3068 ERR("Unable to set group on " LTTNG_RUNDIR
);
3072 /* lttng client socket path */
3073 ret
= chown(client_unix_sock_path
, 0, gid
);
3075 ERR("Unable to set group on %s", client_unix_sock_path
);
3079 /* kconsumerd error socket path */
3080 ret
= chown(kconsumerd_err_unix_sock_path
, 0, gid
);
3082 ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path
);
3086 DBG("All permissions are set");
3093 * Create the pipe used to wake up the kernel thread.
3095 static int create_kernel_poll_pipe(void)
3097 return pipe2(kernel_poll_pipe
, O_CLOEXEC
);
3101 * Create the application command pipe to wake thread_manage_apps.
3103 static int create_apps_cmd_pipe(void)
3105 return pipe2(apps_cmd_pipe
, O_CLOEXEC
);
3109 * Create the lttng run directory needed for all global sockets and pipe.
3111 static int create_lttng_rundir(void)
3115 ret
= mkdir(LTTNG_RUNDIR
, S_IRWXU
| S_IRWXG
);
3117 if (errno
!= EEXIST
) {
3118 ERR("Unable to create " LTTNG_RUNDIR
);
3130 * Setup sockets and directory needed by the kconsumerd communication with the
3133 static int set_kconsumerd_sockets(void)
3137 if (strlen(kconsumerd_err_unix_sock_path
) == 0) {
3138 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
, KCONSUMERD_ERR_SOCK_PATH
);
3141 if (strlen(kconsumerd_cmd_unix_sock_path
) == 0) {
3142 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
, KCONSUMERD_CMD_SOCK_PATH
);
3145 ret
= mkdir(KCONSUMERD_PATH
, S_IRWXU
| S_IRWXG
);
3147 if (errno
!= EEXIST
) {
3148 ERR("Failed to create " KCONSUMERD_PATH
);
3154 /* Create the kconsumerd error unix socket */
3155 kconsumerd_err_sock
= lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path
);
3156 if (kconsumerd_err_sock
< 0) {
3157 ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path
);
3162 /* File permission MUST be 660 */
3163 ret
= chmod(kconsumerd_err_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
3165 ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path
);
3175 * Signal handler for the daemon
3177 * Simply stop all worker threads, leaving main() return gracefully
3178 * after joining all threads and calling cleanup().
3180 static void sighandler(int sig
)
3184 DBG("SIGPIPE catched");
3187 DBG("SIGINT catched");
3191 DBG("SIGTERM catched");
3200 * Setup signal handler for :
3201 * SIGINT, SIGTERM, SIGPIPE
3203 static int set_signal_handler(void)
3206 struct sigaction sa
;
3209 if ((ret
= sigemptyset(&sigset
)) < 0) {
3210 perror("sigemptyset");
3214 sa
.sa_handler
= sighandler
;
3215 sa
.sa_mask
= sigset
;
3217 if ((ret
= sigaction(SIGTERM
, &sa
, NULL
)) < 0) {
3218 perror("sigaction");
3222 if ((ret
= sigaction(SIGINT
, &sa
, NULL
)) < 0) {
3223 perror("sigaction");
3227 if ((ret
= sigaction(SIGPIPE
, &sa
, NULL
)) < 0) {
3228 perror("sigaction");
3232 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
3238 * Set open files limit to unlimited. This daemon can open a large number of
3239 * file descriptors in order to consumer multiple kernel traces.
3241 static void set_ulimit(void)
3246 /* The kernel does not allowed an infinite limit for open files */
3247 lim
.rlim_cur
= 65535;
3248 lim
.rlim_max
= 65535;
3250 ret
= setrlimit(RLIMIT_NOFILE
, &lim
);
3252 perror("failed to set open files limit");
3259 int main(int argc
, char **argv
)
3263 const char *home_path
;
3265 tracepoint(sessiond_boot_start
);
3267 /* Create thread quit pipe */
3268 if ((ret
= init_thread_quit_pipe()) < 0) {
3272 /* Parse arguments */
3274 if ((ret
= parse_args(argc
, argv
) < 0)) {
3287 /* Check if daemon is UID = 0 */
3288 is_root
= !getuid();
3291 ret
= create_lttng_rundir();
3296 if (strlen(apps_unix_sock_path
) == 0) {
3297 snprintf(apps_unix_sock_path
, PATH_MAX
,
3298 DEFAULT_GLOBAL_APPS_UNIX_SOCK
);
3301 if (strlen(client_unix_sock_path
) == 0) {
3302 snprintf(client_unix_sock_path
, PATH_MAX
,
3303 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
);
3306 /* Set global SHM for ust */
3307 if (strlen(wait_shm_path
) == 0) {
3308 snprintf(wait_shm_path
, PATH_MAX
,
3309 DEFAULT_GLOBAL_APPS_WAIT_SHM_PATH
);
3312 home_path
= get_home_dir();
3313 if (home_path
== NULL
) {
3314 /* TODO: Add --socket PATH option */
3315 ERR("Can't get HOME directory for sockets creation.");
3320 if (strlen(apps_unix_sock_path
) == 0) {
3321 snprintf(apps_unix_sock_path
, PATH_MAX
,
3322 DEFAULT_HOME_APPS_UNIX_SOCK
, home_path
);
3325 /* Set the cli tool unix socket path */
3326 if (strlen(client_unix_sock_path
) == 0) {
3327 snprintf(client_unix_sock_path
, PATH_MAX
,
3328 DEFAULT_HOME_CLIENT_UNIX_SOCK
, home_path
);
3331 /* Set global SHM for ust */
3332 if (strlen(wait_shm_path
) == 0) {
3333 snprintf(wait_shm_path
, PATH_MAX
,
3334 DEFAULT_HOME_APPS_WAIT_SHM_PATH
, geteuid());
3338 DBG("Client socket path %s", client_unix_sock_path
);
3339 DBG("Application socket path %s", apps_unix_sock_path
);
3342 * See if daemon already exist.
3344 if ((ret
= check_existing_daemon()) < 0) {
3345 ERR("Already running daemon.\n");
3347 * We do not goto exit because we must not cleanup()
3348 * because a daemon is already running.
3353 /* After this point, we can safely call cleanup() so goto error is used */
3356 * These actions must be executed as root. We do that *after* setting up
3357 * the sockets path because we MUST make the check for another daemon using
3358 * those paths *before* trying to set the kernel consumer sockets and init
3362 ret
= set_kconsumerd_sockets();
3367 /* Setup kernel tracer */
3368 init_kernel_tracer();
3370 /* Set ulimit for open files */
3374 if ((ret
= set_signal_handler()) < 0) {
3378 /* Setup the needed unix socket */
3379 if ((ret
= init_daemon_socket()) < 0) {
3383 /* Set credentials to socket */
3384 if (is_root
&& ((ret
= set_permissions()) < 0)) {
3388 /* Get parent pid if -S, --sig-parent is specified. */
3389 if (opt_sig_parent
) {
3393 /* Setup the kernel pipe for waking up the kernel thread */
3394 if ((ret
= create_kernel_poll_pipe()) < 0) {
3398 /* Setup the thread apps communication pipe. */
3399 if ((ret
= create_apps_cmd_pipe()) < 0) {
3403 /* Init UST command queue. */
3404 cds_wfq_init(&ust_cmd_queue
.queue
);
3407 * Get session list pointer. This pointer MUST NOT be free().
3408 * This list is statically declared in session.c
3410 session_list_ptr
= get_session_list();
3412 /* Set up max poll set size */
3413 lttng_poll_set_max_size();
3415 /* Create thread to manage the client socket */
3416 ret
= pthread_create(&client_thread
, NULL
,
3417 thread_manage_clients
, (void *) NULL
);
3419 perror("pthread_create clients");
3423 /* Create thread to dispatch registration */
3424 ret
= pthread_create(&dispatch_thread
, NULL
,
3425 thread_dispatch_ust_registration
, (void *) NULL
);
3427 perror("pthread_create dispatch");
3431 /* Create thread to manage application registration. */
3432 ret
= pthread_create(®_apps_thread
, NULL
,
3433 thread_registration_apps
, (void *) NULL
);
3435 perror("pthread_create registration");
3439 /* Create thread to manage application socket */
3440 ret
= pthread_create(&apps_thread
, NULL
, thread_manage_apps
, (void *) NULL
);
3442 perror("pthread_create apps");
3446 /* Create kernel thread to manage kernel event */
3447 ret
= pthread_create(&kernel_thread
, NULL
, thread_manage_kernel
, (void *) NULL
);
3449 perror("pthread_create kernel");
3453 tracepoint(sessiond_boot_end
);
3455 ret
= pthread_join(kernel_thread
, &status
);
3457 perror("pthread_join");
3458 goto error
; /* join error, exit without cleanup */
3462 ret
= pthread_join(apps_thread
, &status
);
3464 perror("pthread_join");
3465 goto error
; /* join error, exit without cleanup */
3469 ret
= pthread_join(reg_apps_thread
, &status
);
3471 perror("pthread_join");
3472 goto error
; /* join error, exit without cleanup */
3476 ret
= pthread_join(dispatch_thread
, &status
);
3478 perror("pthread_join");
3479 goto error
; /* join error, exit without cleanup */
3483 ret
= pthread_join(client_thread
, &status
);
3485 perror("pthread_join");
3486 goto error
; /* join error, exit without cleanup */
3489 ret
= join_kconsumerd_thread();
3491 perror("join_kconsumerd");
3492 goto error
; /* join error, exit without cleanup */
3498 * cleanup() is called when no other thread is running.