2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25 #include <semaphore.h>
32 #include <sys/socket.h>
34 #include <sys/types.h>
36 #include <sys/resource.h>
39 #include <urcu/list.h> /* URCU list library (-lurcu) */
40 #include <lttng/lttng.h>
42 #include "liblttsessiondcomm.h"
43 #include "ltt-sessiond.h"
45 #include "kernel-ctl.h"
48 #include "traceable-app.h"
49 #include "lttng-kconsumerd.h"
50 #include "libustctl.h"
54 * teardown: signal SIGTERM handler -> write into pipe. Threads waits
55 * with epoll on pipe and on other pipes/sockets for commands. Main
56 * simply waits on pthread join.
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_quiet
; /* Not static for lttngerr.h */
69 const char *opt_tracing_group
;
70 static int opt_sig_parent
;
71 static int opt_daemon
;
72 static int is_root
; /* Set to 1 if the daemon is running as root */
73 static pid_t ppid
; /* Parent PID for --sig-parent option */
74 static pid_t kconsumerd_pid
;
76 static char apps_unix_sock_path
[PATH_MAX
]; /* Global application Unix socket path */
77 static char client_unix_sock_path
[PATH_MAX
]; /* Global client Unix socket path */
78 static char kconsumerd_err_unix_sock_path
[PATH_MAX
]; /* kconsumerd error Unix socket path */
79 static char kconsumerd_cmd_unix_sock_path
[PATH_MAX
]; /* kconsumerd command Unix socket path */
82 static int client_sock
;
84 static int kconsumerd_err_sock
;
85 static int kconsumerd_cmd_sock
;
86 static int kernel_tracer_fd
;
88 /* Pthread, Mutexes and Semaphores */
89 static pthread_t kconsumerd_thread
;
90 static pthread_t apps_thread
;
91 static pthread_t client_thread
;
92 static sem_t kconsumerd_sem
;
94 static pthread_mutex_t kconsumerd_pid_mutex
; /* Mutex to control kconsumerd pid assignation */
97 * teardown_kernel_session
99 * Complete teardown of a kernel session. This free all data structure
100 * related to a kernel session and update counter.
102 static void teardown_kernel_session(struct ltt_session
*session
)
104 if (session
->kernel_session
!= NULL
) {
105 DBG("Tearing down kernel session");
106 trace_destroy_kernel_session(session
->kernel_session
);
107 /* Extra precaution */
108 session
->kernel_session
= NULL
;
109 /* Decrement session count */
110 session
->kern_session_count
--;
117 * Cleanup the daemon on exit
119 static void cleanup()
123 struct ltt_session
*sess
;
128 MSG("\n%c[%d;%dm*** assert failed *** ==> %c[%dm", 27,1,31,27,0);
129 MSG("%c[%d;%dmMatthew, BEET driven development works!%c[%dm",27,1,33,27,0);
132 /* Stopping all threads */
133 DBG("Terminating all threads");
134 pthread_cancel(client_thread
);
135 pthread_cancel(apps_thread
);
136 if (kconsumerd_pid
!= 0) {
137 pthread_cancel(kconsumerd_thread
);
140 DBG("Unlinking all unix socket");
141 unlink(client_unix_sock_path
);
142 unlink(apps_unix_sock_path
);
143 unlink(kconsumerd_err_unix_sock_path
);
145 DBG("Removing %s directory", LTTNG_RUNDIR
);
146 ret
= asprintf(&cmd
, "rm -rf " LTTNG_RUNDIR
);
148 ERR("asprintf failed. Something is really wrong!");
151 /* Remove lttng run directory */
154 ERR("Unable to clean " LTTNG_RUNDIR
);
157 DBG("Cleaning up all session");
158 /* Cleanup ALL session */
159 cds_list_for_each_entry(sess
, <t_session_list
.head
, list
) {
160 teardown_kernel_session(sess
);
161 // TODO complete session cleanup (including UST)
164 DBG("Closing kernel fd");
165 close(kernel_tracer_fd
);
171 * Send data on a unix socket using the liblttsessiondcomm API.
173 * Return lttcomm error code.
175 static int send_unix_sock(int sock
, void *buf
, size_t len
)
177 /* Check valid length */
182 return lttcomm_send_unix_sock(sock
, buf
, len
);
188 * Free memory of a command context structure.
190 static void clean_command_ctx(struct command_ctx
*cmd_ctx
)
192 DBG("Clean command context structure %p", cmd_ctx
);
206 * send_kconsumerd_fds
208 * Send all stream fds of the kernel session to the consumer.
210 static int send_kconsumerd_fds(int sock
, struct ltt_kernel_session
*session
)
214 struct ltt_kernel_stream
*stream
;
215 struct ltt_kernel_channel
*chan
;
216 struct lttcomm_kconsumerd_header lkh
;
217 struct lttcomm_kconsumerd_msg lkm
;
219 nb_fd
= session
->stream_count_global
;
222 lkh
.payload_size
= (nb_fd
+ 1) * sizeof(struct lttcomm_kconsumerd_msg
);
223 lkh
.cmd_type
= ADD_STREAM
;
225 DBG("Sending kconsumerd header");
227 ret
= lttcomm_send_unix_sock(sock
, &lkh
, sizeof(struct lttcomm_kconsumerd_header
));
229 perror("send kconsumerd header");
233 DBG("Sending metadata stream fd");
235 /* Send metadata stream fd first */
236 lkm
.fd
= session
->metadata_stream_fd
;
237 lkm
.state
= ACTIVE_FD
;
238 lkm
.max_sb_size
= session
->metadata
->conf
->attr
.subbuf_size
;
239 strncpy(lkm
.path_name
, session
->metadata
->pathname
, PATH_MAX
);
241 ret
= lttcomm_send_fds_unix_sock(sock
, &lkm
, &lkm
.fd
, 1, sizeof(lkm
));
243 perror("send kconsumerd fd");
247 cds_list_for_each_entry(chan
, &session
->channel_list
.head
, list
) {
248 cds_list_for_each_entry(stream
, &chan
->stream_list
.head
, list
) {
250 lkm
.state
= stream
->state
;
251 lkm
.max_sb_size
= chan
->channel
->attr
.subbuf_size
;
252 strncpy(lkm
.path_name
, stream
->pathname
, PATH_MAX
);
254 DBG("Sending fd %d to kconsumerd", lkm
.fd
);
256 ret
= lttcomm_send_fds_unix_sock(sock
, &lkm
, &lkm
.fd
, 1, sizeof(lkm
));
258 perror("send kconsumerd fd");
264 DBG("Kconsumerd fds sent");
275 * Create the trace output directory.
277 static int create_trace_dir(struct ltt_kernel_session
*session
)
280 struct ltt_kernel_channel
*chan
;
282 /* Create all channel directories */
283 cds_list_for_each_entry(chan
, &session
->channel_list
.head
, list
) {
284 DBG("Creating trace directory at %s", chan
->pathname
);
285 // TODO: recursive create dir
286 ret
= mkdir(chan
->pathname
, S_IRWXU
| S_IRWXG
);
289 perror("mkdir trace path");
305 * Return a socket connected to the libust communication socket
306 * of the application identified by the pid.
308 * If the pid is not found in the traceable list,
309 * return -1 to indicate error.
311 static int ust_connect_app(pid_t pid
)
314 struct ltt_traceable_app
*lta
;
316 DBG("Connect to application pid %d", pid
);
318 lta
= find_app_by_pid(pid
);
321 DBG("Application pid %d not found", pid
);
325 sock
= ustctl_connect_pid(lta
->pid
);
327 ERR("Fail connecting to the PID %d", pid
);
336 * Notify apps by writing 42 to a named pipe using name.
337 * Every applications waiting for a ltt-sessiond will be notified
338 * and re-register automatically to the session daemon.
340 * Return open or write error value.
342 static int notify_apps(const char *name
)
347 DBG("Notify the global application pipe");
349 /* Try opening the global pipe */
350 fd
= open(name
, O_WRONLY
);
355 /* Notify by writing on the pipe */
356 ret
= write(fd
, "42", 2);
368 * Setup the outgoing data buffer for the response (llm) by allocating the
369 * right amount of memory and copying the original information from the lsm
372 * Return total size of the buffer pointed by buf.
374 static int setup_lttng_msg(struct command_ctx
*cmd_ctx
, size_t size
)
380 cmd_ctx
->llm
= malloc(sizeof(struct lttcomm_lttng_msg
) + buf_size
);
381 if (cmd_ctx
->llm
== NULL
) {
387 /* Copy common data */
388 cmd_ctx
->llm
->cmd_type
= cmd_ctx
->lsm
->cmd_type
;
389 cmd_ctx
->llm
->pid
= cmd_ctx
->lsm
->pid
;
391 cmd_ctx
->llm
->data_size
= size
;
392 cmd_ctx
->lttng_msg_size
= sizeof(struct lttcomm_lttng_msg
) + buf_size
;
401 * thread_manage_kconsumerd
403 * This thread manage the kconsumerd error sent
404 * back to the session daemon.
406 static void *thread_manage_kconsumerd(void *data
)
409 enum lttcomm_return_code code
;
411 DBG("[thread] Manage kconsumerd started");
413 ret
= lttcomm_listen_unix_sock(kconsumerd_err_sock
);
418 sock
= lttcomm_accept_unix_sock(kconsumerd_err_sock
);
423 /* Getting status code from kconsumerd */
424 ret
= lttcomm_recv_unix_sock(sock
, &code
, sizeof(enum lttcomm_return_code
));
429 if (code
== KCONSUMERD_COMMAND_SOCK_READY
) {
430 kconsumerd_cmd_sock
= lttcomm_connect_unix_sock(kconsumerd_cmd_unix_sock_path
);
431 if (kconsumerd_cmd_sock
< 0) {
432 sem_post(&kconsumerd_sem
);
433 perror("kconsumerd connect");
436 /* Signal condition to tell that the kconsumerd is ready */
437 sem_post(&kconsumerd_sem
);
438 DBG("Kconsumerd command socket ready");
440 DBG("Kconsumerd error when waiting for SOCK_READY : %s",
441 lttcomm_get_readable_code(-code
));
445 /* Wait for any kconsumerd error */
446 ret
= lttcomm_recv_unix_sock(sock
, &code
, sizeof(enum lttcomm_return_code
));
448 ERR("Kconsumerd closed the command socket");
452 ERR("Kconsumerd return code : %s", lttcomm_get_readable_code(-code
));
456 DBG("Kconsumerd thread dying");
463 * This thread manage the application socket communication
465 static void *thread_manage_apps(void *data
)
469 /* TODO: Something more elegant is needed but fine for now */
470 /* FIXME: change all types to either uint8_t, uint32_t, uint64_t
471 * for 32-bit vs 64-bit compat processes. */
472 /* replicate in ust with version number */
474 int reg
; /* 1:register, 0:unregister */
479 DBG("[thread] Manage apps started");
481 ret
= lttcomm_listen_unix_sock(apps_sock
);
486 /* Notify all applications to register */
487 notify_apps(default_global_apps_pipe
);
490 DBG("Accepting application registration");
491 /* Blocking call, waiting for transmission */
492 sock
= lttcomm_accept_unix_sock(apps_sock
);
497 /* Basic recv here to handle the very simple data
498 * that the libust send to register (reg_msg).
500 ret
= recv(sock
, ®_msg
, sizeof(reg_msg
), 0);
506 /* Add application to the global traceable list */
507 if (reg_msg
.reg
== 1) {
509 ret
= register_traceable_app(reg_msg
.pid
, reg_msg
.uid
);
511 /* register_traceable_app only return an error with
512 * ENOMEM. At this point, we better stop everything.
518 unregister_traceable_app(reg_msg
.pid
);
528 * spawn_kconsumerd_thread
530 * Start the thread_manage_kconsumerd. This must be done after a kconsumerd
531 * exec or it will fails.
533 static int spawn_kconsumerd_thread(void)
537 /* Setup semaphore */
538 sem_init(&kconsumerd_sem
, 0, 0);
540 ret
= pthread_create(&kconsumerd_thread
, NULL
, thread_manage_kconsumerd
, (void *) NULL
);
542 perror("pthread_create kconsumerd");
546 /* Wait for the kconsumerd thread to be ready */
547 sem_wait(&kconsumerd_sem
);
549 if (kconsumerd_pid
== 0) {
550 ERR("Kconsumerd did not start");
557 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
564 * Fork and exec a kernel consumer daemon (kconsumerd).
566 * NOTE: It is very important to fork a kconsumerd BEFORE opening any kernel
567 * file descriptor using the libkernelctl or kernel-ctl functions. So, a
568 * kernel consumer MUST only be spawned before creating a kernel session.
570 * Return pid if successful else -1.
572 static pid_t
spawn_kconsumerd(void)
577 DBG("Spawning kconsumerd");
584 execlp("kconsumerd", "kconsumerd", "--verbose", NULL
);
586 perror("kernel start consumer exec");
589 } else if (pid
> 0) {
593 perror("kernel start consumer fork");
605 * Spawn the kconsumerd daemon and session daemon thread.
607 static int start_kconsumerd(void)
611 pthread_mutex_lock(&kconsumerd_pid_mutex
);
612 if (kconsumerd_pid
!= 0) {
616 ret
= spawn_kconsumerd();
618 ERR("Spawning kconsumerd failed");
619 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
620 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
624 /* Setting up the global kconsumerd_pid */
625 kconsumerd_pid
= ret
;
626 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
628 DBG("Kconsumerd pid %d", ret
);
630 DBG("Spawning kconsumerd thread");
631 ret
= spawn_kconsumerd_thread();
633 ERR("Fatal error spawning kconsumerd thread");
638 pthread_mutex_unlock(&kconsumerd_pid_mutex
);
648 * Setup necessary data for kernel tracer action.
650 static void init_kernel_tracer(void)
652 /* Set the global kernel tracer fd */
653 kernel_tracer_fd
= open(DEFAULT_KERNEL_TRACER_PATH
, O_RDWR
);
654 if (kernel_tracer_fd
< 0) {
655 WARN("No kernel tracer available");
656 kernel_tracer_fd
= 0;
659 DBG("Kernel tracer fd %d", kernel_tracer_fd
);
665 * Start tracing by creating trace directory and sending FDs to the kernel
668 static int start_kernel_trace(struct ltt_kernel_session
*session
)
672 /* Create trace directory */
673 ret
= create_trace_dir(session
);
675 if (ret
== -EEXIST
) {
676 ret
= LTTCOMM_KERN_DIR_EXIST
;
678 ret
= LTTCOMM_KERN_DIR_FAIL
;
683 if (session
->kconsumer_fds_sent
== 0) {
684 ret
= send_kconsumerd_fds(kconsumerd_cmd_sock
, session
);
686 ERR("Send kconsumerd fds failed");
687 ret
= LTTCOMM_KERN_CONSUMER_FAIL
;
691 session
->kconsumer_fds_sent
= 1;
699 * init_default_channel
701 * Allocate a channel structure and fill it.
703 static struct lttng_channel
*init_default_channel(void)
705 struct lttng_channel
*chan
;
707 chan
= malloc(sizeof(struct lttng_channel
));
709 perror("init channel malloc");
713 if (snprintf(chan
->name
, NAME_MAX
, DEFAULT_CHANNEL_NAME
) < 0) {
714 perror("snprintf defautl channel name");
718 chan
->attr
.overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
719 chan
->attr
.subbuf_size
= DEFAULT_CHANNEL_SUBBUF_SIZE
;
720 chan
->attr
.num_subbuf
= DEFAULT_CHANNEL_SUBBUF_NUM
;
721 chan
->attr
.switch_timer_interval
= DEFAULT_CHANNEL_SWITCH_TIMER
;
722 chan
->attr
.read_timer_interval
= DEFAULT_CHANNEL_READ_TIMER
;
729 * create_kernel_session
731 * Create a kernel tracer session then create the default channel.
733 static int create_kernel_session(struct ltt_session
*session
)
736 struct lttng_channel
*chan
;
738 DBG("Creating kernel session");
740 ret
= kernel_create_session(session
, kernel_tracer_fd
);
742 ret
= LTTCOMM_KERN_SESS_FAIL
;
746 chan
= init_default_channel();
752 DBG("Creating default kernel channel %s", DEFAULT_CHANNEL_NAME
);
754 ret
= kernel_create_channel(session
->kernel_session
, chan
);
756 ret
= LTTCOMM_KERN_CHAN_FAIL
;
767 * Process the command requested by the lttng client within the command
768 * context structure. This function make sure that the return structure (llm)
769 * is set and ready for transmission before returning.
771 * Return any error encountered or 0 for success.
773 static int process_client_msg(struct command_ctx
*cmd_ctx
)
777 DBG("Processing client command %d", cmd_ctx
->lsm
->cmd_type
);
779 /* Listing commands don't need a session */
780 switch (cmd_ctx
->lsm
->cmd_type
) {
781 case LTTNG_CREATE_SESSION
:
782 case LTTNG_LIST_SESSIONS
:
783 case LTTNG_LIST_EVENTS
:
784 case LTTNG_KERNEL_LIST_EVENTS
:
785 case LTTNG_LIST_TRACEABLE_APPS
:
788 DBG("Getting session %s by name", cmd_ctx
->lsm
->session_name
);
789 cmd_ctx
->session
= find_session_by_name(cmd_ctx
->lsm
->session_name
);
790 if (cmd_ctx
->session
== NULL
) {
791 /* If session name not found */
792 if (cmd_ctx
->lsm
->session_name
!= NULL
) {
793 ret
= LTTCOMM_SESS_NOT_FOUND
;
794 } else { /* If no session name specified */
795 ret
= LTTCOMM_SELECT_SESS
;
803 * Check kernel command for kernel session.
805 switch (cmd_ctx
->lsm
->cmd_type
) {
806 case LTTNG_KERNEL_CREATE_CHANNEL
:
807 case LTTNG_KERNEL_DISABLE_ALL_EVENT
:
808 case LTTNG_KERNEL_DISABLE_CHANNEL
:
809 case LTTNG_KERNEL_DISABLE_EVENT
:
810 case LTTNG_KERNEL_ENABLE_ALL_EVENT
:
811 case LTTNG_KERNEL_ENABLE_CHANNEL
:
812 case LTTNG_KERNEL_ENABLE_EVENT
:
813 case LTTNG_KERNEL_LIST_EVENTS
:
814 /* Kernel tracer check */
815 if (kernel_tracer_fd
== 0) {
816 init_kernel_tracer();
817 if (kernel_tracer_fd
== 0) {
818 ret
= LTTCOMM_KERN_NA
;
823 /* Need a session for kernel command */
824 if (cmd_ctx
->lsm
->cmd_type
!= LTTNG_KERNEL_LIST_EVENTS
&&
825 cmd_ctx
->session
->kernel_session
== NULL
) {
827 ret
= create_kernel_session(cmd_ctx
->session
);
829 ret
= LTTCOMM_KERN_SESS_FAIL
;
833 /* Start the kernel consumer daemon */
834 if (kconsumerd_pid
== 0) {
835 ret
= start_kconsumerd();
843 /* Connect to ust apps if available pid */
844 if (cmd_ctx
->lsm
->pid
> 0) {
845 /* Connect to app using ustctl API */
846 cmd_ctx
->ust_sock
= ust_connect_app(cmd_ctx
->lsm
->pid
);
847 if (cmd_ctx
->ust_sock
< 0) {
848 ret
= LTTCOMM_NO_TRACEABLE
;
853 /* Process by command type */
854 switch (cmd_ctx
->lsm
->cmd_type
) {
855 case LTTNG_KERNEL_CREATE_CHANNEL
:
857 /* Setup lttng message with no payload */
858 ret
= setup_lttng_msg(cmd_ctx
, 0);
864 DBG("Creating kernel channel");
866 ret
= kernel_create_channel(cmd_ctx
->session
->kernel_session
,
867 &cmd_ctx
->lsm
->u
.channel
.chan
);
869 ret
= LTTCOMM_KERN_CHAN_FAIL
;
876 case LTTNG_KERNEL_DISABLE_EVENT
:
878 struct ltt_kernel_channel
*chan
;
879 struct ltt_kernel_event
*ev
;
881 /* Setup lttng message with no payload */
882 ret
= setup_lttng_msg(cmd_ctx
, 0);
887 chan
= get_kernel_channel_by_name(cmd_ctx
->lsm
->u
.disable
.channel_name
,
888 cmd_ctx
->session
->kernel_session
);
890 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
894 ev
= get_kernel_event_by_name(cmd_ctx
->lsm
->u
.disable
.name
, chan
);
896 DBG("Disabling kernel event %s for channel %s.",
897 cmd_ctx
->lsm
->u
.disable
.name
, cmd_ctx
->lsm
->u
.disable
.channel_name
);
898 ret
= kernel_disable_event(ev
);
900 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
905 kernel_wait_quiescent(kernel_tracer_fd
);
909 case LTTNG_KERNEL_ENABLE_EVENT
:
911 struct ltt_kernel_channel
*chan
;
912 struct ltt_kernel_event
*ev
;
914 /* Setup lttng message with no payload */
915 ret
= setup_lttng_msg(cmd_ctx
, 0);
920 chan
= get_kernel_channel_by_name(cmd_ctx
->lsm
->u
.enable
.channel_name
,
921 cmd_ctx
->session
->kernel_session
);
923 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
927 ev
= get_kernel_event_by_name(cmd_ctx
->lsm
->u
.enable
.event
.name
, chan
);
929 DBG("Creating kernel event %s for channel %s.",
930 cmd_ctx
->lsm
->u
.enable
.event
.name
, cmd_ctx
->lsm
->u
.enable
.channel_name
);
931 ret
= kernel_create_event(&cmd_ctx
->lsm
->u
.enable
.event
, chan
);
933 DBG("Enabling kernel event %s for channel %s.",
934 cmd_ctx
->lsm
->u
.enable
.event
.name
, cmd_ctx
->lsm
->u
.enable
.channel_name
);
935 ret
= kernel_enable_event(ev
);
939 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
943 kernel_wait_quiescent(kernel_tracer_fd
);
947 case LTTNG_KERNEL_ENABLE_ALL_EVENT
:
949 int pos
, size
, found
;
950 char *event_list
, *event
, *ptr
;
951 struct ltt_kernel_channel
*chan
;
952 struct lttng_event ev
;
954 /* Setup lttng message with no payload */
955 ret
= setup_lttng_msg(cmd_ctx
, 0);
960 DBG("Enabling all kernel event");
962 size
= kernel_list_events(kernel_tracer_fd
, &event_list
);
964 ret
= LTTCOMM_KERN_LIST_FAIL
;
968 /* Get channel by name and create event for that channel */
969 cds_list_for_each_entry(chan
, &cmd_ctx
->session
->kernel_session
->channel_list
.head
, list
) {
970 if (strcmp(cmd_ctx
->lsm
->u
.enable
.channel_name
, chan
->channel
->name
) == 0) {
977 ret
= LTTCOMM_KERN_CHAN_NOT_FOUND
;
982 while ((size
= sscanf(ptr
, "event { name = %m[^;]; };%n\n", &event
, &pos
)) == 1) {
983 strncpy(ev
.name
, event
, LTTNG_SYM_NAME_LEN
);
984 /* Default event type for enable all */
985 ev
.type
= LTTNG_EVENT_TRACEPOINTS
;
986 /* Enable each single tracepoint event */
987 ret
= kernel_create_event(&ev
, chan
);
989 ret
= LTTCOMM_KERN_ENABLE_FAIL
;
992 /* Move pointer to the next line */
999 /* Quiescent wait after event enable */
1000 kernel_wait_quiescent(kernel_tracer_fd
);
1004 case LTTNG_KERNEL_LIST_EVENTS
:
1009 DBG("Listing kernel events");
1011 size
= kernel_list_events(kernel_tracer_fd
, &event_list
);
1013 ret
= LTTCOMM_KERN_LIST_FAIL
;
1018 * Setup lttng message with payload size set to the event list size in
1019 * bytes and then copy list into the llm payload.
1021 ret
= setup_lttng_msg(cmd_ctx
, size
);
1026 /* Copy event list into message payload */
1027 memcpy(cmd_ctx
->llm
->payload
, event_list
, size
);
1034 case LTTNG_START_TRACE
:
1036 struct ltt_kernel_channel
*chan
;
1038 /* Setup lttng message with no payload */
1039 ret
= setup_lttng_msg(cmd_ctx
, 0);
1044 /* Kernel tracing */
1045 if (cmd_ctx
->session
->kernel_session
!= NULL
) {
1046 if (cmd_ctx
->session
->kernel_session
->metadata
== NULL
) {
1047 DBG("Open kernel metadata");
1048 ret
= kernel_open_metadata(cmd_ctx
->session
->kernel_session
);
1050 ret
= LTTCOMM_KERN_META_FAIL
;
1055 if (cmd_ctx
->session
->kernel_session
->metadata_stream_fd
== 0) {
1056 DBG("Opening kernel metadata stream");
1057 if (cmd_ctx
->session
->kernel_session
->metadata_stream_fd
== 0) {
1058 ret
= kernel_open_metadata_stream(cmd_ctx
->session
->kernel_session
);
1060 ERR("Kernel create metadata stream failed");
1061 ret
= LTTCOMM_KERN_STREAM_FAIL
;
1067 /* For each channel */
1068 cds_list_for_each_entry(chan
, &cmd_ctx
->session
->kernel_session
->channel_list
.head
, list
) {
1069 if (chan
->stream_count
== 0) {
1070 ret
= kernel_open_channel_stream(chan
);
1072 ERR("Kernel create channel stream failed");
1073 ret
= LTTCOMM_KERN_STREAM_FAIL
;
1076 /* Update the stream global counter */
1077 cmd_ctx
->session
->kernel_session
->stream_count_global
+= ret
;
1081 DBG("Start kernel tracing");
1082 ret
= kernel_start_session(cmd_ctx
->session
->kernel_session
);
1084 ERR("Kernel start session failed");
1085 ret
= LTTCOMM_KERN_START_FAIL
;
1089 ret
= start_kernel_trace(cmd_ctx
->session
->kernel_session
);
1091 ret
= LTTCOMM_KERN_START_FAIL
;
1095 /* Quiescent wait after starting trace */
1096 kernel_wait_quiescent(kernel_tracer_fd
);
1099 /* TODO: Start all UST traces */
1104 case LTTNG_STOP_TRACE
:
1106 struct ltt_kernel_channel
*chan
;
1107 /* Setup lttng message with no payload */
1108 ret
= setup_lttng_msg(cmd_ctx
, 0);
1114 if (cmd_ctx
->session
->kernel_session
!= NULL
) {
1115 DBG("Stop kernel tracing");
1117 ret
= kernel_metadata_flush_buffer(cmd_ctx
->session
->kernel_session
->metadata_stream_fd
);
1119 ERR("Kernel metadata flush failed");
1122 cds_list_for_each_entry(chan
, &cmd_ctx
->session
->kernel_session
->channel_list
.head
, list
) {
1123 ret
= kernel_flush_buffer(chan
);
1125 ERR("Kernel flush buffer error");
1129 ret
= kernel_stop_session(cmd_ctx
->session
->kernel_session
);
1131 ERR("Kernel stop session failed");
1132 ret
= LTTCOMM_KERN_STOP_FAIL
;
1136 /* Quiescent wait after stopping trace */
1137 kernel_wait_quiescent(kernel_tracer_fd
);
1140 /* TODO : User-space tracer */
1145 case LTTNG_CREATE_SESSION
:
1147 /* Setup lttng message with no payload */
1148 ret
= setup_lttng_msg(cmd_ctx
, 0);
1153 ret
= create_session(cmd_ctx
->lsm
->session_name
, cmd_ctx
->lsm
->path
);
1155 if (ret
== -EEXIST
) {
1156 ret
= LTTCOMM_EXIST_SESS
;
1158 ret
= LTTCOMM_FATAL
;
1166 case LTTNG_DESTROY_SESSION
:
1168 /* Setup lttng message with no payload */
1169 ret
= setup_lttng_msg(cmd_ctx
, 0);
1174 /* Clean kernel session teardown */
1175 teardown_kernel_session(cmd_ctx
->session
);
1177 ret
= destroy_session(cmd_ctx
->lsm
->session_name
);
1179 ret
= LTTCOMM_FATAL
;
1187 case LTTNG_LIST_TRACES:
1189 unsigned int trace_count;
1191 trace_count = get_trace_count_per_session(cmd_ctx->session);
1192 if (trace_count == 0) {
1193 ret = LTTCOMM_NO_TRACE;
1197 ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_trace) * trace_count);
1202 get_traces_per_session(cmd_ctx->session,
1203 (struct lttng_trace *)(cmd_ctx->llm->payload));
1210 case UST_CREATE_TRACE:
1212 ret = setup_lttng_msg(cmd_ctx, 0);
1217 ret = ust_create_trace(cmd_ctx);
1224 case LTTNG_LIST_TRACEABLE_APPS
:
1226 unsigned int app_count
;
1228 app_count
= get_app_count();
1229 DBG("Traceable application count : %d", app_count
);
1230 if (app_count
== 0) {
1231 ret
= LTTCOMM_NO_APPS
;
1235 ret
= setup_lttng_msg(cmd_ctx
, sizeof(pid_t
) * app_count
);
1240 get_app_list_pids((pid_t
*)(cmd_ctx
->llm
->payload
));
1246 case UST_START_TRACE:
1248 ret = setup_lttng_msg(cmd_ctx, 0);
1253 ret = ust_start_trace(cmd_ctx);
1259 case UST_STOP_TRACE:
1261 ret = setup_lttng_msg(cmd_ctx, 0);
1266 ret = ust_stop_trace(cmd_ctx);
1273 case LTTNG_LIST_SESSIONS
:
1275 unsigned int session_count
;
1277 session_count
= get_session_count();
1278 if (session_count
== 0) {
1279 ret
= LTTCOMM_NO_SESSION
;
1283 ret
= setup_lttng_msg(cmd_ctx
, sizeof(struct lttng_session
) * session_count
);
1288 get_lttng_session((struct lttng_session
*)(cmd_ctx
->llm
->payload
));
1294 /* Undefined command */
1295 ret
= setup_lttng_msg(cmd_ctx
, 0);
1304 /* Set return code */
1305 cmd_ctx
->llm
->ret_code
= ret
;
1310 if (cmd_ctx
->llm
== NULL
) {
1311 DBG("Missing llm structure. Allocating one.");
1312 if (setup_lttng_msg(cmd_ctx
, 0) < 0) {
1316 /* Notify client of error */
1317 cmd_ctx
->llm
->ret_code
= ret
;
1324 * thread_manage_clients
1326 * This thread manage all clients request using the unix
1327 * client socket for communication.
1329 static void *thread_manage_clients(void *data
)
1332 struct command_ctx
*cmd_ctx
;
1334 DBG("[thread] Manage client started");
1336 ret
= lttcomm_listen_unix_sock(client_sock
);
1341 /* Notify parent pid that we are ready
1342 * to accept command for client side.
1344 if (opt_sig_parent
) {
1345 kill(ppid
, SIGCHLD
);
1349 /* Blocking call, waiting for transmission */
1350 DBG("Accepting client command ...");
1351 sock
= lttcomm_accept_unix_sock(client_sock
);
1356 /* Allocate context command to process the client request */
1357 cmd_ctx
= malloc(sizeof(struct command_ctx
));
1359 /* Allocate data buffer for reception */
1360 cmd_ctx
->lsm
= malloc(sizeof(struct lttcomm_session_msg
));
1361 cmd_ctx
->llm
= NULL
;
1362 cmd_ctx
->session
= NULL
;
1365 * Data is received from the lttng client. The struct
1366 * lttcomm_session_msg (lsm) contains the command and data request of
1369 DBG("Receiving data from client ...");
1370 ret
= lttcomm_recv_unix_sock(sock
, cmd_ctx
->lsm
, sizeof(struct lttcomm_session_msg
));
1375 // TODO: Validate cmd_ctx including sanity check for security purpose.
1378 * This function dispatch the work to the kernel or userspace tracer
1379 * libs and fill the lttcomm_lttng_msg data structure of all the needed
1380 * informations for the client. The command context struct contains
1381 * everything this function may needs.
1383 ret
= process_client_msg(cmd_ctx
);
1385 /* TODO: Inform client somehow of the fatal error. At this point,
1386 * ret < 0 means that a malloc failed (ENOMEM). */
1387 /* Error detected but still accept command */
1388 clean_command_ctx(cmd_ctx
);
1392 DBG("Sending response (size: %d, retcode: %d)",
1393 cmd_ctx
->lttng_msg_size
, cmd_ctx
->llm
->ret_code
);
1394 ret
= send_unix_sock(sock
, cmd_ctx
->llm
, cmd_ctx
->lttng_msg_size
);
1396 ERR("Failed to send data back to client");
1399 clean_command_ctx(cmd_ctx
);
1401 /* End of transmission */
1411 * usage function on stderr
1413 static void usage(void)
1415 fprintf(stderr
, "Usage: %s OPTIONS\n\nOptions:\n", progname
);
1416 fprintf(stderr
, " -h, --help Display this usage.\n");
1417 fprintf(stderr
, " -c, --client-sock PATH Specify path for the client unix socket\n");
1418 fprintf(stderr
, " -a, --apps-sock PATH Specify path for apps unix socket\n");
1419 fprintf(stderr
, " --kconsumerd-err-sock PATH Specify path for the kernel consumer error socket\n");
1420 fprintf(stderr
, " --kconsumerd-cmd-sock PATH Specify path for the kernel consumer command socket\n");
1421 fprintf(stderr
, " -d, --daemonize Start as a daemon.\n");
1422 fprintf(stderr
, " -g, --group NAME Specify the tracing group name. (default: tracing)\n");
1423 fprintf(stderr
, " -V, --version Show version number.\n");
1424 fprintf(stderr
, " -S, --sig-parent Send SIGCHLD to parent pid to notify readiness.\n");
1425 fprintf(stderr
, " -q, --quiet No output at all.\n");
1426 fprintf(stderr
, " -v, --verbose Verbose mode. Activate DBG() macro.\n");
1430 * daemon argument parsing
1432 static int parse_args(int argc
, char **argv
)
1436 static struct option long_options
[] = {
1437 { "client-sock", 1, 0, 'c' },
1438 { "apps-sock", 1, 0, 'a' },
1439 { "kconsumerd-cmd-sock", 1, 0, 0 },
1440 { "kconsumerd-err-sock", 1, 0, 0 },
1441 { "daemonize", 0, 0, 'd' },
1442 { "sig-parent", 0, 0, 'S' },
1443 { "help", 0, 0, 'h' },
1444 { "group", 1, 0, 'g' },
1445 { "version", 0, 0, 'V' },
1446 { "quiet", 0, 0, 'q' },
1447 { "verbose", 0, 0, 'v' },
1452 int option_index
= 0;
1453 c
= getopt_long(argc
, argv
, "dhqvVS" "a:c:g:s:E:C:", long_options
, &option_index
);
1460 fprintf(stderr
, "option %s", long_options
[option_index
].name
);
1462 fprintf(stderr
, " with arg %s\n", optarg
);
1466 snprintf(client_unix_sock_path
, PATH_MAX
, "%s", optarg
);
1469 snprintf(apps_unix_sock_path
, PATH_MAX
, "%s", optarg
);
1475 opt_tracing_group
= strdup(optarg
);
1481 fprintf(stdout
, "%s\n", VERSION
);
1487 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
, "%s", optarg
);
1490 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
, "%s", optarg
);
1499 /* Unknown option or other error.
1500 * Error is printed by getopt, just return */
1509 * init_daemon_socket
1511 * Creates the two needed socket by the daemon.
1512 * apps_sock - The communication socket for all UST apps.
1513 * client_sock - The communication of the cli tool (lttng).
1515 static int init_daemon_socket()
1520 old_umask
= umask(0);
1522 /* Create client tool unix socket */
1523 client_sock
= lttcomm_create_unix_sock(client_unix_sock_path
);
1524 if (client_sock
< 0) {
1525 ERR("Create unix sock failed: %s", client_unix_sock_path
);
1530 /* File permission MUST be 660 */
1531 ret
= chmod(client_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
1533 ERR("Set file permissions failed: %s", client_unix_sock_path
);
1538 /* Create the application unix socket */
1539 apps_sock
= lttcomm_create_unix_sock(apps_unix_sock_path
);
1540 if (apps_sock
< 0) {
1541 ERR("Create unix sock failed: %s", apps_unix_sock_path
);
1546 /* File permission MUST be 666 */
1547 ret
= chmod(apps_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
| S_IROTH
| S_IWOTH
);
1549 ERR("Set file permissions failed: %s", apps_unix_sock_path
);
1560 * check_existing_daemon
1562 * Check if the global socket is available.
1563 * If yes, error is returned.
1565 static int check_existing_daemon()
1569 ret
= access(client_unix_sock_path
, F_OK
);
1571 ret
= access(apps_unix_sock_path
, F_OK
);
1580 * Return pointer to home directory path using
1581 * the env variable HOME.
1585 static const char *get_home_dir(void)
1587 const char *home_path
;
1589 if ((home_path
= (const char *) getenv("HOME")) == NULL
) {
1590 home_path
= default_home_dir
;
1599 * Set the tracing group gid onto the client socket.
1601 * Race window between mkdir and chown is OK because we are going from
1602 * less permissive (root.root) to more permissive (root.tracing).
1604 static int set_permissions(void)
1609 /* Decide which group name to use */
1610 (opt_tracing_group
!= NULL
) ?
1611 (grp
= getgrnam(opt_tracing_group
)) :
1612 (grp
= getgrnam(default_tracing_group
));
1615 ERR("Missing tracing group. Aborting execution.\n");
1620 /* Set lttng run dir */
1621 ret
= chown(LTTNG_RUNDIR
, 0, grp
->gr_gid
);
1623 ERR("Unable to set group on " LTTNG_RUNDIR
);
1627 /* lttng client socket path */
1628 ret
= chown(client_unix_sock_path
, 0, grp
->gr_gid
);
1630 ERR("Unable to set group on %s", client_unix_sock_path
);
1634 /* kconsumerd error socket path */
1635 ret
= chown(kconsumerd_err_unix_sock_path
, 0, grp
->gr_gid
);
1637 ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path
);
1641 DBG("All permissions are set");
1648 * create_lttng_rundir
1650 * Create the lttng run directory needed for all
1651 * global sockets and pipe.
1653 static int create_lttng_rundir(void)
1657 ret
= mkdir(LTTNG_RUNDIR
, S_IRWXU
| S_IRWXG
);
1659 if (errno
!= EEXIST
) {
1660 ERR("Unable to create " LTTNG_RUNDIR
);
1672 * set_kconsumerd_sockets
1674 * Setup sockets and directory needed by the kconsumerd
1675 * communication with the session daemon.
1677 static int set_kconsumerd_sockets(void)
1681 if (strlen(kconsumerd_err_unix_sock_path
) == 0) {
1682 snprintf(kconsumerd_err_unix_sock_path
, PATH_MAX
, KCONSUMERD_ERR_SOCK_PATH
);
1685 if (strlen(kconsumerd_cmd_unix_sock_path
) == 0) {
1686 snprintf(kconsumerd_cmd_unix_sock_path
, PATH_MAX
, KCONSUMERD_CMD_SOCK_PATH
);
1689 ret
= mkdir(KCONSUMERD_PATH
, S_IRWXU
| S_IRWXG
);
1691 if (errno
!= EEXIST
) {
1692 ERR("Failed to create " KCONSUMERD_PATH
);
1698 /* Create the kconsumerd error unix socket */
1699 kconsumerd_err_sock
= lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path
);
1700 if (kconsumerd_err_sock
< 0) {
1701 ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path
);
1706 /* File permission MUST be 660 */
1707 ret
= chmod(kconsumerd_err_unix_sock_path
, S_IRUSR
| S_IWUSR
| S_IRGRP
| S_IWGRP
);
1709 ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path
);
1721 * Signal handler for the daemon
1723 static void sighandler(int sig
)
1727 DBG("SIGPIPE catched");
1730 DBG("SIGINT catched");
1734 DBG("SIGTERM catched");
1745 * set_signal_handler
1747 * Setup signal handler for :
1748 * SIGINT, SIGTERM, SIGPIPE
1750 static int set_signal_handler(void)
1753 struct sigaction sa
;
1756 if ((ret
= sigemptyset(&sigset
)) < 0) {
1757 perror("sigemptyset");
1761 sa
.sa_handler
= sighandler
;
1762 sa
.sa_mask
= sigset
;
1764 if ((ret
= sigaction(SIGTERM
, &sa
, NULL
)) < 0) {
1765 perror("sigaction");
1769 if ((ret
= sigaction(SIGINT
, &sa
, NULL
)) < 0) {
1770 perror("sigaction");
1774 if ((ret
= sigaction(SIGPIPE
, &sa
, NULL
)) < 0) {
1775 perror("sigaction");
1779 DBG("Signal handler set for SIGTERM, SIGPIPE and SIGINT");
1787 * Set open files limit to unlimited. This daemon can open a large number of
1788 * file descriptors in order to consumer multiple kernel traces.
1790 static void set_ulimit(void)
1795 lim
.rlim_cur
= 65535;
1796 lim
.rlim_max
= 65535;
1798 ret
= setrlimit(RLIMIT_NOFILE
, &lim
);
1800 perror("failed to set open files limit");
1807 int main(int argc
, char **argv
)
1812 /* Parse arguments */
1814 if ((ret
= parse_args(argc
, argv
) < 0)) {
1827 /* Check if daemon is UID = 0 */
1828 is_root
= !getuid();
1830 /* Set all sockets path */
1832 ret
= create_lttng_rundir();
1837 if (strlen(apps_unix_sock_path
) == 0) {
1838 snprintf(apps_unix_sock_path
, PATH_MAX
,
1839 DEFAULT_GLOBAL_APPS_UNIX_SOCK
);
1842 if (strlen(client_unix_sock_path
) == 0) {
1843 snprintf(client_unix_sock_path
, PATH_MAX
,
1844 DEFAULT_GLOBAL_CLIENT_UNIX_SOCK
);
1847 ret
= set_kconsumerd_sockets();
1852 /* Setup kernel tracer */
1853 init_kernel_tracer();
1855 /* Set ulimit for open files */
1858 if (strlen(apps_unix_sock_path
) == 0) {
1859 snprintf(apps_unix_sock_path
, PATH_MAX
,
1860 DEFAULT_HOME_APPS_UNIX_SOCK
, get_home_dir());
1863 /* Set the cli tool unix socket path */
1864 if (strlen(client_unix_sock_path
) == 0) {
1865 snprintf(client_unix_sock_path
, PATH_MAX
,
1866 DEFAULT_HOME_CLIENT_UNIX_SOCK
, get_home_dir());
1870 DBG("Client socket path %s", client_unix_sock_path
);
1871 DBG("Application socket path %s", apps_unix_sock_path
);
1873 /* See if daemon already exist. If any of the two
1874 * socket needed by the daemon are present, this test fails
1876 if ((ret
= check_existing_daemon()) == 0) {
1877 ERR("Already running daemon.\n");
1878 /* We do not goto error because we must not
1879 * cleanup() because a daemon is already running.
1884 if (set_signal_handler() < 0) {
1888 /* Setup the needed unix socket */
1889 if (init_daemon_socket() < 0) {
1893 /* Set credentials to socket */
1894 if (is_root
&& (set_permissions() < 0)) {
1898 /* Get parent pid if -S, --sig-parent is specified. */
1899 if (opt_sig_parent
) {
1904 /* Create thread to manage the client socket */
1905 ret
= pthread_create(&client_thread
, NULL
, thread_manage_clients
, (void *) NULL
);
1907 perror("pthread_create");
1911 /* Create thread to manage application socket */
1912 ret
= pthread_create(&apps_thread
, NULL
, thread_manage_apps
, (void *) NULL
);
1914 perror("pthread_create");
1918 ret
= pthread_join(client_thread
, &status
);
1920 perror("pthread_join");