2 * SPDX-License-Identifier: LGPL-2.1-only
4 * Copyright (C) 2011 EfficiOS Inc.
5 * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
11 #include <sys/types.h>
12 #include <sys/socket.h>
15 #include <sys/types.h>
22 #include <semaphore.h>
27 #include <urcu/uatomic.h>
28 #include <urcu/compiler.h>
29 #include <lttng/urcu/urcu-ust.h>
31 #include <lttng/ust-utils.h>
32 #include <lttng/ust-events.h>
33 #include <lttng/ust-abi.h>
34 #include <lttng/ust-fork.h>
35 #include <lttng/ust-error.h>
36 #include <lttng/ust-ctl.h>
37 #include <lttng/ust-libc-wrapper.h>
38 #include <lttng/ust-thread.h>
39 #include <lttng/ust-tracer.h>
40 #include <lttng/ust-common.h>
41 #include <lttng/ust-cancelstate.h>
42 #include <urcu/tls-compat.h>
43 #include "lib/lttng-ust/futex.h"
44 #include "common/ustcomm.h"
45 #include "common/ust-fd.h"
46 #include "common/logging.h"
47 #include "common/macros.h"
48 #include "common/tracepoint.h"
49 #include "lttng-tracer-core.h"
50 #include "common/compat/pthread.h"
51 #include "common/procname.h"
52 #include "common/ringbuffer/rb-init.h"
53 #include "lttng-ust-statedump.h"
54 #include "common/clock.h"
55 #include "common/getenv.h"
56 #include "lib/lttng-ust/events.h"
57 #include "context-internal.h"
58 #include "common/align.h"
59 #include "common/counter-clients/clients.h"
60 #include "common/ringbuffer-clients/clients.h"
63 * Has lttng ust comm constructor been called ?
65 static int initialized
;
68 * The ust_lock/ust_unlock lock is used as a communication thread mutex.
69 * Held when handling a command, also held by fork() to deal with
70 * removal of threads, and by exit path.
72 * The UST lock is the centralized mutex across UST tracing control and
75 * ust_exit_mutex must never nest in ust_mutex.
77 * ust_fork_mutex must never nest in ust_mutex.
79 * ust_mutex_nest is a per-thread nesting counter, allowing the perf
80 * counter lazy initialization called by events within the statedump,
81 * which traces while the ust_mutex is held.
83 * ust_lock nests within the dynamic loader lock (within glibc) because
84 * it is taken within the library constructor.
86 * The ust fd tracker lock nests within the ust_mutex.
88 static pthread_mutex_t ust_mutex
= PTHREAD_MUTEX_INITIALIZER
;
90 /* Allow nesting the ust_mutex within the same thread. */
91 static DEFINE_URCU_TLS(int, ust_mutex_nest
);
94 * ust_exit_mutex protects thread_active variable wrt thread exit. It
95 * cannot be done by ust_mutex because pthread_cancel(), which takes an
96 * internal libc lock, cannot nest within ust_mutex.
98 * It never nests within a ust_mutex.
100 static pthread_mutex_t ust_exit_mutex
= PTHREAD_MUTEX_INITIALIZER
;
103 * ust_fork_mutex protects base address statedump tracing against forks. It
104 * prevents the dynamic loader lock to be taken (by base address statedump
105 * tracing) while a fork is happening, thus preventing deadlock issues with
106 * the dynamic loader lock.
108 static pthread_mutex_t ust_fork_mutex
= PTHREAD_MUTEX_INITIALIZER
;
110 /* Should the ust comm thread quit ? */
111 static int lttng_ust_comm_should_quit
;
114 * This variable can be tested by applications to check whether
115 * lttng-ust is loaded. They simply have to define their own
116 * "lttng_ust_loaded" weak symbol, and test it. It is set to 1 by the
117 * library constructor.
119 int lttng_ust_loaded
__attribute__((weak
));
122 * Notes on async-signal-safety of ust lock: a few libc functions are used
123 * which are not strictly async-signal-safe:
125 * - pthread_setcancelstate
126 * - pthread_mutex_lock
127 * - pthread_mutex_unlock
129 * As of glibc 2.35, the implementation of pthread_setcancelstate only
130 * touches TLS data, and it appears to be safe to use from signal
131 * handlers. If the libc implementation changes, this will need to be
132 * revisited, and we may ask glibc to provide an async-signal-safe
133 * pthread_setcancelstate.
135 * As of glibc 2.35, the implementation of pthread_mutex_lock/unlock
136 * for fast mutexes only relies on the pthread_mutex_t structure.
137 * Disabling signals around all uses of this mutex ensures
138 * signal-safety. If the libc implementation changes and eventually uses
139 * other global resources, this will need to be revisited and we may
140 * need to implement our own mutex.
144 * Return 0 on success, -1 if should quit.
145 * The lock is taken in both cases.
150 sigset_t sig_all_blocked
, orig_mask
;
153 if (lttng_ust_cancelstate_disable_push()) {
154 ERR("lttng_ust_cancelstate_disable_push");
156 sigfillset(&sig_all_blocked
);
157 ret
= pthread_sigmask(SIG_SETMASK
, &sig_all_blocked
, &orig_mask
);
159 ERR("pthread_sigmask: ret=%d", ret
);
161 if (!URCU_TLS(ust_mutex_nest
)++)
162 pthread_mutex_lock(&ust_mutex
);
163 ret
= pthread_sigmask(SIG_SETMASK
, &orig_mask
, NULL
);
165 ERR("pthread_sigmask: ret=%d", ret
);
167 if (lttng_ust_comm_should_quit
) {
175 * ust_lock_nocheck() can be used in constructors/destructors, because
176 * they are already nested within the dynamic loader lock, and therefore
177 * have exclusive access against execution of liblttng-ust destructor.
180 void ust_lock_nocheck(void)
182 sigset_t sig_all_blocked
, orig_mask
;
185 if (lttng_ust_cancelstate_disable_push()) {
186 ERR("lttng_ust_cancelstate_disable_push");
188 sigfillset(&sig_all_blocked
);
189 ret
= pthread_sigmask(SIG_SETMASK
, &sig_all_blocked
, &orig_mask
);
191 ERR("pthread_sigmask: ret=%d", ret
);
193 if (!URCU_TLS(ust_mutex_nest
)++)
194 pthread_mutex_lock(&ust_mutex
);
195 ret
= pthread_sigmask(SIG_SETMASK
, &orig_mask
, NULL
);
197 ERR("pthread_sigmask: ret=%d", ret
);
204 void ust_unlock(void)
206 sigset_t sig_all_blocked
, orig_mask
;
209 sigfillset(&sig_all_blocked
);
210 ret
= pthread_sigmask(SIG_SETMASK
, &sig_all_blocked
, &orig_mask
);
212 ERR("pthread_sigmask: ret=%d", ret
);
214 if (!--URCU_TLS(ust_mutex_nest
))
215 pthread_mutex_unlock(&ust_mutex
);
216 ret
= pthread_sigmask(SIG_SETMASK
, &orig_mask
, NULL
);
218 ERR("pthread_sigmask: ret=%d", ret
);
220 if (lttng_ust_cancelstate_disable_pop()) {
221 ERR("lttng_ust_cancelstate_disable_pop");
226 * Wait for either of these before continuing to the main
228 * - the register_done message from sessiond daemon
229 * (will let the sessiond daemon enable sessions before main
231 * - sessiond daemon is not reachable.
232 * - timeout (ensuring applications are resilient to session
235 static sem_t constructor_wait
;
237 * Doing this for the ust_app, global and local sessiond.
240 sem_count_initial_value
= 6,
243 static int sem_count
= sem_count_initial_value
;
246 * Counting nesting within lttng-ust. Used to ensure that calling fork()
247 * from liblttng-ust does not execute the pre/post fork handlers.
249 static DEFINE_URCU_TLS(int, lttng_ust_nest_count
);
252 * Info about socket and associated listener thread.
256 pthread_t ust_listener
; /* listener thread */
258 int registration_done
;
263 char sock_path
[PATH_MAX
];
268 * If wait_shm_is_file is true, use standard open to open and
269 * create the shared memory used for waiting on session daemon.
270 * Otherwise, use shm_open to create this file.
272 bool wait_shm_is_file
;
273 char wait_shm_path
[PATH_MAX
];
276 /* Keep track of lazy state dump not performed yet. */
277 int statedump_pending
;
278 int initial_statedump_done
;
279 /* Keep procname for statedump */
280 char procname
[LTTNG_UST_CONTEXT_PROCNAME_LEN
];
283 /* Socket from app (connect) to session daemon (listen) for communication */
284 static struct sock_info ust_app
= {
289 .registration_done
= 0,
296 .wait_shm_is_file
= true,
298 .statedump_pending
= 0,
299 .initial_statedump_done
= 0,
304 static struct sock_info global_apps
= {
309 .registration_done
= 0,
313 .sock_path
= LTTNG_DEFAULT_RUNDIR
"/" LTTNG_UST_SOCK_FILENAME
,
317 .wait_shm_is_file
= false,
318 .wait_shm_path
= "/" LTTNG_UST_WAIT_FILENAME
,
320 .statedump_pending
= 0,
321 .initial_statedump_done
= 0,
325 static struct sock_info local_apps
= {
329 .registration_done
= 0,
330 .allowed
= 0, /* Check setuid bit first */
336 .wait_shm_is_file
= false,
338 .statedump_pending
= 0,
339 .initial_statedump_done
= 0,
343 static int wait_poll_fallback
;
345 static const char *cmd_name_mapping
[] = {
346 [ LTTNG_UST_ABI_RELEASE
] = "Release",
347 [ LTTNG_UST_ABI_SESSION
] = "Create Session",
348 [ LTTNG_UST_ABI_TRACER_VERSION
] = "Get Tracer Version",
350 [ LTTNG_UST_ABI_TRACEPOINT_LIST
] = "Create Tracepoint List",
351 [ LTTNG_UST_ABI_WAIT_QUIESCENT
] = "Wait for Quiescent State",
352 [ LTTNG_UST_ABI_REGISTER_DONE
] = "Registration Done",
353 [ LTTNG_UST_ABI_TRACEPOINT_FIELD_LIST
] = "Create Tracepoint Field List",
355 [ LTTNG_UST_ABI_EVENT_NOTIFIER_GROUP_CREATE
] = "Create event notifier group",
357 /* Session FD commands */
358 [ LTTNG_UST_ABI_CHANNEL
] = "Create Channel",
359 [ LTTNG_UST_ABI_SESSION_START
] = "Start Session",
360 [ LTTNG_UST_ABI_SESSION_STOP
] = "Stop Session",
362 /* Channel FD commands */
363 [ LTTNG_UST_ABI_STREAM
] = "Create Stream",
364 [ LTTNG_UST_ABI_EVENT
] = "Create Event",
366 /* Event and Channel FD commands */
367 [ LTTNG_UST_ABI_CONTEXT
] = "Create Context",
368 [ LTTNG_UST_ABI_FLUSH_BUFFER
] = "Flush Buffer",
370 /* Event, Channel and Session commands */
371 [ LTTNG_UST_ABI_ENABLE
] = "Enable",
372 [ LTTNG_UST_ABI_DISABLE
] = "Disable",
374 /* Tracepoint list commands */
375 [ LTTNG_UST_ABI_TRACEPOINT_LIST_GET
] = "List Next Tracepoint",
376 [ LTTNG_UST_ABI_TRACEPOINT_FIELD_LIST_GET
] = "List Next Tracepoint Field",
378 /* Event FD commands */
379 [ LTTNG_UST_ABI_FILTER
] = "Create Filter",
380 [ LTTNG_UST_ABI_EXCLUSION
] = "Add exclusions to event",
382 /* Event notifier group commands */
383 [ LTTNG_UST_ABI_EVENT_NOTIFIER_CREATE
] = "Create event notifier",
385 /* Session and event notifier group commands */
386 [ LTTNG_UST_ABI_COUNTER
] = "Create Counter",
388 /* Counter commands */
389 [ LTTNG_UST_ABI_COUNTER_GLOBAL
] = "Create Counter Global",
390 [ LTTNG_UST_ABI_COUNTER_CPU
] = "Create Counter CPU",
393 static const char *str_timeout
;
394 static int got_timeout_env
;
396 static char *get_map_shm(struct sock_info
*sock_info
);
399 * Returns the HOME directory path. Caller MUST NOT free(3) the returned
403 const char *get_lttng_home_dir(void)
407 val
= (const char *) lttng_ust_getenv("LTTNG_HOME");
411 return (const char *) lttng_ust_getenv("HOME");
415 * Returns the LTTNG_UST_APP_PATH path. If environment variable exists
416 * and contains a ':', the first path before the ':' separator is returned.
417 * The return value should be freed by the caller if it is not NULL.
420 char *get_lttng_ust_app_path(void)
422 const char *env_val
= lttng_ust_getenv("LTTNG_UST_APP_PATH");
427 sep
= strchr((char*)env_val
, ':');
430 * Split into multiple paths using ':' as a separator.
431 * There is no escaping of the ':' separator.
433 WARN("':' separator in LTTNG_UST_APP_PATH, only the first path will be used.");
434 val
= zmalloc(sep
- env_val
+ 1);
436 PERROR("zmalloc get_lttng_ust_app_path");
439 memcpy(val
, env_val
, sep
- env_val
);
440 val
[sep
- env_val
] = '\0';
442 val
= strdup(env_val
);
454 * Force a read (imply TLS allocation for dlopen) of TLS variables.
457 void lttng_ust_nest_count_alloc_tls(void)
459 __asm__
__volatile__ ("" : : "m" (URCU_TLS(lttng_ust_nest_count
)));
463 void lttng_ust_mutex_nest_alloc_tls(void)
465 __asm__
__volatile__ ("" : : "m" (URCU_TLS(ust_mutex_nest
)));
469 * Allocate lttng-ust urcu TLS.
472 void lttng_ust_urcu_alloc_tls(void)
474 (void) lttng_ust_urcu_read_ongoing();
477 void lttng_ust_common_init_thread(int flags
)
479 lttng_ust_urcu_alloc_tls();
480 lttng_ringbuffer_alloc_tls();
481 lttng_ust_vtid_init_thread(flags
);
482 lttng_ust_nest_count_alloc_tls();
483 lttng_ust_procname_init_thread(flags
);
484 lttng_ust_mutex_nest_alloc_tls();
485 lttng_ust_perf_counter_init_thread(flags
);
486 lttng_ust_common_alloc_tls();
487 lttng_ust_cgroup_ns_init_thread(flags
);
488 lttng_ust_ipc_ns_init_thread(flags
);
489 lttng_ust_net_ns_init_thread(flags
);
490 lttng_ust_time_ns_init_thread(flags
);
491 lttng_ust_uts_ns_init_thread(flags
);
492 lttng_ust_ring_buffer_client_discard_alloc_tls();
493 lttng_ust_ring_buffer_client_discard_rt_alloc_tls();
494 lttng_ust_ring_buffer_client_overwrite_alloc_tls();
495 lttng_ust_ring_buffer_client_overwrite_rt_alloc_tls();
499 * LTTng-UST uses Global Dynamic model TLS variables rather than IE
500 * model because many versions of glibc don't preallocate a pool large
501 * enough for TLS variables IE model defined in other shared libraries,
502 * and causes issues when using LTTng-UST for Java tracing.
504 * Because of this use of Global Dynamic TLS variables, users wishing to
505 * trace from signal handlers need to explicitly trigger the lazy
506 * allocation of those variables for each thread before using them.
507 * This can be triggered by calling lttng_ust_init_thread().
509 void lttng_ust_init_thread(void)
512 * Because those TLS variables are global dynamic, we need to
513 * ensure those are initialized before a signal handler nesting over
514 * this thread attempts to use them.
516 lttng_ust_common_init_thread(LTTNG_UST_INIT_THREAD_MASK
);
518 lttng_ust_urcu_register_thread();
521 int lttng_get_notify_socket(void *owner
)
523 struct sock_info
*info
= owner
;
525 return info
->notify_socket
;
529 char* lttng_ust_sockinfo_get_procname(void *owner
)
531 struct sock_info
*info
= owner
;
533 return info
->procname
;
537 void print_cmd(int cmd
, int handle
)
539 const char *cmd_name
= "Unknown";
541 if (cmd
>= 0 && cmd
< LTTNG_ARRAY_SIZE(cmd_name_mapping
)
542 && cmd_name_mapping
[cmd
]) {
543 cmd_name
= cmd_name_mapping
[cmd
];
545 DBG("Message Received \"%s\" (%d), Handle \"%s\" (%d)",
547 lttng_ust_obj_get_name(handle
), handle
);
551 int setup_ust_apps(void)
553 char *ust_app_path
= NULL
;
557 assert(!ust_app
.wait_shm_mmap
);
561 * Disallow ust apps tracing for setuid binaries, because we
562 * cannot use the environment variables anyway.
564 if (uid
!= geteuid()) {
565 DBG("UST app tracing disabled for setuid binary.");
566 assert(ust_app
.allowed
== 0);
570 ust_app_path
= get_lttng_ust_app_path();
572 DBG("LTTNG_UST_APP_PATH environment variable not set.");
573 assert(ust_app
.allowed
== 0);
578 * The LTTNG_UST_APP_PATH env. var. disables global and local
579 * sessiond connections.
582 snprintf(ust_app
.sock_path
, PATH_MAX
, "%s/%s",
583 ust_app_path
, LTTNG_UST_SOCK_FILENAME
);
584 snprintf(ust_app
.wait_shm_path
, PATH_MAX
, "%s/%s",
586 LTTNG_UST_WAIT_FILENAME
);
588 ust_app
.wait_shm_mmap
= get_map_shm(&ust_app
);
589 if (!ust_app
.wait_shm_mmap
) {
590 WARN("Unable to get map shm for ust_app. Disabling LTTng-UST ust_app tracing.");
596 lttng_pthread_getname_np(ust_app
.procname
, LTTNG_UST_CONTEXT_PROCNAME_LEN
);
604 int setup_global_apps(void)
607 assert(!global_apps
.wait_shm_mmap
);
610 * The LTTNG_UST_APP_PATH env. var. disables global sessiond
616 global_apps
.wait_shm_mmap
= get_map_shm(&global_apps
);
617 if (!global_apps
.wait_shm_mmap
) {
618 WARN("Unable to get map shm for global apps. Disabling LTTng-UST global tracing.");
619 global_apps
.allowed
= 0;
624 global_apps
.allowed
= 1;
625 lttng_pthread_getname_np(global_apps
.procname
, LTTNG_UST_CONTEXT_PROCNAME_LEN
);
631 int setup_local_apps(void)
634 const char *home_dir
;
637 assert(!local_apps
.wait_shm_mmap
);
640 * The LTTNG_UST_APP_PATH env. var. disables local sessiond
648 * Disallow per-user tracing for setuid binaries.
650 if (uid
!= geteuid()) {
651 assert(local_apps
.allowed
== 0);
655 home_dir
= get_lttng_home_dir();
657 WARN("HOME environment variable not set. Disabling LTTng-UST per-user tracing.");
658 assert(local_apps
.allowed
== 0);
662 local_apps
.allowed
= 1;
663 snprintf(local_apps
.sock_path
, PATH_MAX
, "%s/%s/%s",
665 LTTNG_DEFAULT_HOME_RUNDIR
,
666 LTTNG_UST_SOCK_FILENAME
);
667 snprintf(local_apps
.wait_shm_path
, PATH_MAX
, "/%s-%u",
668 LTTNG_UST_WAIT_FILENAME
,
671 local_apps
.wait_shm_mmap
= get_map_shm(&local_apps
);
672 if (!local_apps
.wait_shm_mmap
) {
673 WARN("Unable to get map shm for local apps. Disabling LTTng-UST per-user tracing.");
674 local_apps
.allowed
= 0;
679 lttng_pthread_getname_np(local_apps
.procname
, LTTNG_UST_CONTEXT_PROCNAME_LEN
);
685 * Get socket timeout, in ms.
686 * -1: wait forever. 0: don't wait. >0: timeout, in ms.
689 long get_timeout(void)
691 long constructor_delay_ms
= LTTNG_UST_DEFAULT_CONSTRUCTOR_TIMEOUT_MS
;
693 if (!got_timeout_env
) {
694 str_timeout
= lttng_ust_getenv("LTTNG_UST_REGISTER_TIMEOUT");
698 constructor_delay_ms
= strtol(str_timeout
, NULL
, 10);
699 /* All negative values are considered as "-1". */
700 if (constructor_delay_ms
< -1)
701 constructor_delay_ms
= -1;
702 return constructor_delay_ms
;
705 /* Timeout for notify socket send and recv. */
707 long get_notify_sock_timeout(void)
709 return get_timeout();
712 /* Timeout for connecting to cmd and notify sockets. */
714 long get_connect_sock_timeout(void)
716 return get_timeout();
720 * Return values: -1: wait forever. 0: don't wait. 1: timeout wait.
723 int get_constructor_timeout(struct timespec
*constructor_timeout
)
725 long constructor_delay_ms
;
728 constructor_delay_ms
= get_timeout();
730 switch (constructor_delay_ms
) {
731 case -1:/* fall-through */
733 return constructor_delay_ms
;
739 * If we are unable to find the current time, don't wait.
741 ret
= clock_gettime(CLOCK_REALTIME
, constructor_timeout
);
746 constructor_timeout
->tv_sec
+= constructor_delay_ms
/ 1000UL;
747 constructor_timeout
->tv_nsec
+=
748 (constructor_delay_ms
% 1000UL) * 1000000UL;
749 if (constructor_timeout
->tv_nsec
>= 1000000000UL) {
750 constructor_timeout
->tv_sec
++;
751 constructor_timeout
->tv_nsec
-= 1000000000UL;
753 /* Timeout wait (constructor_delay_ms). */
758 void get_allow_blocking(void)
760 const char *str_allow_blocking
=
761 lttng_ust_getenv("LTTNG_UST_ALLOW_BLOCKING");
763 if (str_allow_blocking
) {
764 DBG("%s environment variable is set",
765 "LTTNG_UST_ALLOW_BLOCKING");
766 lttng_ust_ringbuffer_set_allow_blocking();
771 int register_to_sessiond(int socket
, enum lttng_ust_ctl_socket_type type
,
772 const char *procname
)
774 return ustcomm_send_reg_msg(socket
,
777 lttng_ust_rb_alignof(uint8_t) * CHAR_BIT
,
778 lttng_ust_rb_alignof(uint16_t) * CHAR_BIT
,
779 lttng_ust_rb_alignof(uint32_t) * CHAR_BIT
,
780 lttng_ust_rb_alignof(uint64_t) * CHAR_BIT
,
781 lttng_ust_rb_alignof(unsigned long) * CHAR_BIT
,
786 int send_reply(int sock
, struct ustcomm_ust_reply
*lur
)
790 len
= ustcomm_send_unix_sock(sock
, lur
, sizeof(*lur
));
793 DBG("message successfully sent");
796 if (len
== -ECONNRESET
) {
797 DBG("remote end closed connection");
802 DBG("incorrect message size: %zd", len
);
808 void decrement_sem_count(unsigned int count
)
812 assert(uatomic_read(&sem_count
) >= count
);
814 if (uatomic_read(&sem_count
) <= 0) {
818 ret
= uatomic_add_return(&sem_count
, -count
);
820 ret
= sem_post(&constructor_wait
);
826 int handle_register_done(struct sock_info
*sock_info
)
828 if (sock_info
->registration_done
)
830 sock_info
->registration_done
= 1;
832 decrement_sem_count(1);
833 if (!sock_info
->statedump_pending
) {
834 sock_info
->initial_statedump_done
= 1;
835 decrement_sem_count(1);
842 int handle_register_failed(struct sock_info
*sock_info
)
844 if (sock_info
->registration_done
)
846 sock_info
->registration_done
= 1;
847 sock_info
->initial_statedump_done
= 1;
849 decrement_sem_count(2);
855 * Only execute pending statedump after the constructor semaphore has
856 * been posted by the current listener thread. This means statedump will
857 * only be performed after the "registration done" command is received
858 * from this thread's session daemon.
860 * This ensures we don't run into deadlock issues with the dynamic
861 * loader mutex, which is held while the constructor is called and
862 * waiting on the constructor semaphore. All operations requiring this
863 * dynamic loader lock need to be postponed using this mechanism.
865 * In a scenario with two session daemons connected to the application,
866 * it is possible that the first listener thread which receives the
867 * registration done command issues its statedump while the dynamic
868 * loader lock is still held by the application constructor waiting on
869 * the semaphore. It will however be allowed to proceed when the
870 * second session daemon sends the registration done command to the
871 * second listener thread. This situation therefore does not produce
875 void handle_pending_statedump(struct sock_info
*sock_info
)
877 if (sock_info
->registration_done
&& sock_info
->statedump_pending
) {
878 sock_info
->statedump_pending
= 0;
879 pthread_mutex_lock(&ust_fork_mutex
);
880 lttng_handle_pending_statedump(sock_info
);
881 pthread_mutex_unlock(&ust_fork_mutex
);
883 if (!sock_info
->initial_statedump_done
) {
884 sock_info
->initial_statedump_done
= 1;
885 decrement_sem_count(1);
891 const char *bytecode_type_str(uint32_t cmd
)
894 case LTTNG_UST_ABI_CAPTURE
:
896 case LTTNG_UST_ABI_FILTER
:
904 int handle_bytecode_recv(struct sock_info
*sock_info
,
905 int sock
, struct ustcomm_ust_msg
*lum
)
907 struct lttng_ust_bytecode_node
*bytecode
= NULL
;
908 enum lttng_ust_bytecode_type type
;
909 const struct lttng_ust_abi_objd_ops
*ops
;
910 uint32_t data_size
, data_size_max
, reloc_offset
;
916 case LTTNG_UST_ABI_FILTER
:
917 type
= LTTNG_UST_BYTECODE_TYPE_FILTER
;
918 data_size
= lum
->u
.filter
.data_size
;
919 data_size_max
= LTTNG_UST_ABI_FILTER_BYTECODE_MAX_LEN
;
920 reloc_offset
= lum
->u
.filter
.reloc_offset
;
921 seqnum
= lum
->u
.filter
.seqnum
;
923 case LTTNG_UST_ABI_CAPTURE
:
924 type
= LTTNG_UST_BYTECODE_TYPE_CAPTURE
;
925 data_size
= lum
->u
.capture
.data_size
;
926 data_size_max
= LTTNG_UST_ABI_CAPTURE_BYTECODE_MAX_LEN
;
927 reloc_offset
= lum
->u
.capture
.reloc_offset
;
928 seqnum
= lum
->u
.capture
.seqnum
;
934 if (data_size
> data_size_max
) {
935 ERR("Bytecode %s data size is too large: %u bytes",
936 bytecode_type_str(lum
->cmd
), data_size
);
941 if (reloc_offset
> data_size
) {
942 ERR("Bytecode %s reloc offset %u is not within data",
943 bytecode_type_str(lum
->cmd
), reloc_offset
);
948 /* Allocate the structure AND the `data[]` field. */
949 bytecode
= zmalloc(sizeof(*bytecode
) + data_size
);
955 bytecode
->bc
.len
= data_size
;
956 bytecode
->bc
.reloc_offset
= reloc_offset
;
957 bytecode
->bc
.seqnum
= seqnum
;
958 bytecode
->type
= type
;
960 len
= ustcomm_recv_unix_sock(sock
, bytecode
->bc
.data
, bytecode
->bc
.len
);
962 case 0: /* orderly shutdown */
966 if (len
== bytecode
->bc
.len
) {
967 DBG("Bytecode %s data received",
968 bytecode_type_str(lum
->cmd
));
970 } else if (len
< 0) {
971 DBG("Receive failed from lttng-sessiond with errno %d",
973 if (len
== -ECONNRESET
) {
974 ERR("%s remote end closed connection",
982 DBG("Incorrect %s bytecode data message size: %zd",
983 bytecode_type_str(lum
->cmd
), len
);
989 ops
= lttng_ust_abi_objd_ops(lum
->handle
);
996 ret
= ops
->cmd(lum
->handle
, lum
->cmd
,
997 (unsigned long) &bytecode
,
1008 void prepare_cmd_reply(struct ustcomm_ust_reply
*lur
, uint32_t handle
, uint32_t cmd
, int ret
)
1010 lur
->handle
= handle
;
1014 lur
->ret_code
= LTTNG_UST_OK
;
1017 * Use -LTTNG_UST_ERR as wildcard for UST internal
1018 * error that are not caused by the transport, except if
1019 * we already have a more precise error message to
1022 if (ret
> -LTTNG_UST_ERR
) {
1023 /* Translate code to UST error. */
1026 lur
->ret_code
= -LTTNG_UST_ERR_EXIST
;
1029 lur
->ret_code
= -LTTNG_UST_ERR_INVAL
;
1032 lur
->ret_code
= -LTTNG_UST_ERR_NOENT
;
1035 lur
->ret_code
= -LTTNG_UST_ERR_PERM
;
1038 lur
->ret_code
= -LTTNG_UST_ERR_NOSYS
;
1041 lur
->ret_code
= -LTTNG_UST_ERR
;
1045 lur
->ret_code
= ret
;
1051 int handle_message(struct sock_info
*sock_info
,
1052 int sock
, struct ustcomm_ust_msg
*lum
)
1055 const struct lttng_ust_abi_objd_ops
*ops
;
1056 struct ustcomm_ust_reply lur
;
1057 union lttng_ust_abi_args args
;
1058 char ctxstr
[LTTNG_UST_ABI_SYM_NAME_LEN
]; /* App context string. */
1061 memset(&lur
, 0, sizeof(lur
));
1064 ret
= -LTTNG_UST_ERR_EXITING
;
1068 ops
= lttng_ust_abi_objd_ops(lum
->handle
);
1075 case LTTNG_UST_ABI_FILTER
:
1076 case LTTNG_UST_ABI_EXCLUSION
:
1077 case LTTNG_UST_ABI_CHANNEL
:
1078 case LTTNG_UST_ABI_STREAM
:
1079 case LTTNG_UST_ABI_CONTEXT
:
1081 * Those commands send additional payload after struct
1082 * ustcomm_ust_msg, which makes it pretty much impossible to
1083 * deal with "unknown command" errors without leaving the
1084 * communication pipe in a out-of-sync state. This is part of
1085 * the ABI between liblttng-ust-ctl and liblttng-ust, and
1086 * should be fixed on the next breaking
1087 * LTTNG_UST_ABI_MAJOR_VERSION protocol bump by indicating the
1088 * total command message length as part of a message header so
1089 * that the protocol can recover from invalid command errors.
1093 case LTTNG_UST_ABI_CAPTURE
:
1094 case LTTNG_UST_ABI_COUNTER
:
1095 case LTTNG_UST_ABI_COUNTER_GLOBAL
:
1096 case LTTNG_UST_ABI_COUNTER_CPU
:
1097 case LTTNG_UST_ABI_EVENT_NOTIFIER_CREATE
:
1098 case LTTNG_UST_ABI_EVENT_NOTIFIER_GROUP_CREATE
:
1100 * Those commands expect a reply to the struct ustcomm_ust_msg
1101 * before sending additional payload.
1103 prepare_cmd_reply(&lur
, lum
->handle
, lum
->cmd
, 0);
1105 ret
= send_reply(sock
, &lur
);
1107 DBG("error sending reply");
1114 * Other commands either don't send additional payload, or are
1121 case LTTNG_UST_ABI_REGISTER_DONE
:
1122 if (lum
->handle
== LTTNG_UST_ABI_ROOT_HANDLE
)
1123 ret
= handle_register_done(sock_info
);
1127 case LTTNG_UST_ABI_RELEASE
:
1128 if (lum
->handle
== LTTNG_UST_ABI_ROOT_HANDLE
)
1131 ret
= lttng_ust_abi_objd_unref(lum
->handle
, 1);
1133 case LTTNG_UST_ABI_CAPTURE
:
1134 case LTTNG_UST_ABI_FILTER
:
1135 ret
= handle_bytecode_recv(sock_info
, sock
, lum
);
1139 case LTTNG_UST_ABI_EXCLUSION
:
1141 /* Receive exclusion names */
1142 struct lttng_ust_excluder_node
*node
;
1145 count
= lum
->u
.exclusion
.count
;
1147 /* There are no names to read */
1151 node
= zmalloc(sizeof(*node
) +
1152 count
* LTTNG_UST_ABI_SYM_NAME_LEN
);
1157 node
->excluder
.count
= count
;
1158 len
= ustcomm_recv_unix_sock(sock
, node
->excluder
.names
,
1159 count
* LTTNG_UST_ABI_SYM_NAME_LEN
);
1161 case 0: /* orderly shutdown */
1166 if (len
== count
* LTTNG_UST_ABI_SYM_NAME_LEN
) {
1167 DBG("Exclusion data received");
1169 } else if (len
< 0) {
1170 DBG("Receive failed from lttng-sessiond with errno %d", (int) -len
);
1171 if (len
== -ECONNRESET
) {
1172 ERR("%s remote end closed connection", sock_info
->name
);
1181 DBG("Incorrect exclusion data message size: %zd", len
);
1188 ret
= ops
->cmd(lum
->handle
, lum
->cmd
,
1189 (unsigned long) &node
,
1196 case LTTNG_UST_ABI_EVENT_NOTIFIER_GROUP_CREATE
:
1198 int event_notifier_notif_fd
, close_ret
;
1200 len
= ustcomm_recv_event_notifier_notif_fd_from_sessiond(sock
,
1201 &event_notifier_notif_fd
);
1203 case 0: /* orderly shutdown */
1210 DBG("Receive failed from lttng-sessiond with errno %d",
1212 if (len
== -ECONNRESET
) {
1213 ERR("%s remote end closed connection",
1221 DBG("Incorrect event notifier fd message size: %zd",
1227 args
.event_notifier_handle
.event_notifier_notif_fd
=
1228 event_notifier_notif_fd
;
1230 ret
= ops
->cmd(lum
->handle
, lum
->cmd
,
1231 (unsigned long) &lum
->u
,
1235 if (args
.event_notifier_handle
.event_notifier_notif_fd
>= 0) {
1236 lttng_ust_lock_fd_tracker();
1237 close_ret
= close(args
.event_notifier_handle
.event_notifier_notif_fd
);
1238 lttng_ust_unlock_fd_tracker();
1244 case LTTNG_UST_ABI_CHANNEL
:
1249 len
= ustcomm_recv_channel_from_sessiond(sock
,
1250 &chan_data
, lum
->u
.channel
.len
,
1253 case 0: /* orderly shutdown */
1257 if (len
== lum
->u
.channel
.len
) {
1258 DBG("channel data received");
1260 } else if (len
< 0) {
1261 DBG("Receive failed from lttng-sessiond with errno %d", (int) -len
);
1262 if (len
== -ECONNRESET
) {
1263 ERR("%s remote end closed connection", sock_info
->name
);
1270 DBG("incorrect channel data message size: %zd", len
);
1275 args
.channel
.chan_data
= chan_data
;
1276 args
.channel
.wakeup_fd
= wakeup_fd
;
1278 ret
= ops
->cmd(lum
->handle
, lum
->cmd
,
1279 (unsigned long) &lum
->u
,
1283 if (args
.channel
.wakeup_fd
>= 0) {
1286 lttng_ust_lock_fd_tracker();
1287 close_ret
= close(args
.channel
.wakeup_fd
);
1288 lttng_ust_unlock_fd_tracker();
1289 args
.channel
.wakeup_fd
= -1;
1293 free(args
.channel
.chan_data
);
1296 case LTTNG_UST_ABI_STREAM
:
1300 /* Receive shm_fd, wakeup_fd */
1301 ret
= ustcomm_recv_stream_from_sessiond(sock
,
1303 &args
.stream
.shm_fd
,
1304 &args
.stream
.wakeup_fd
);
1310 ret
= ops
->cmd(lum
->handle
, lum
->cmd
,
1311 (unsigned long) &lum
->u
,
1315 if (args
.stream
.shm_fd
>= 0) {
1316 lttng_ust_lock_fd_tracker();
1317 close_ret
= close(args
.stream
.shm_fd
);
1318 lttng_ust_unlock_fd_tracker();
1319 args
.stream
.shm_fd
= -1;
1323 if (args
.stream
.wakeup_fd
>= 0) {
1324 lttng_ust_lock_fd_tracker();
1325 close_ret
= close(args
.stream
.wakeup_fd
);
1326 lttng_ust_unlock_fd_tracker();
1327 args
.stream
.wakeup_fd
= -1;
1333 case LTTNG_UST_ABI_CONTEXT
:
1334 switch (lum
->u
.context
.ctx
) {
1335 case LTTNG_UST_ABI_CONTEXT_APP_CONTEXT
:
1338 size_t ctxlen
, recvlen
;
1340 ctxlen
= strlen("$app.") + lum
->u
.context
.u
.app_ctx
.provider_name_len
- 1
1341 + strlen(":") + lum
->u
.context
.u
.app_ctx
.ctx_name_len
;
1342 if (ctxlen
>= LTTNG_UST_ABI_SYM_NAME_LEN
) {
1343 ERR("Application context string length size is too large: %zu bytes",
1348 strcpy(ctxstr
, "$app.");
1349 p
= &ctxstr
[strlen("$app.")];
1350 recvlen
= ctxlen
- strlen("$app.");
1351 len
= ustcomm_recv_unix_sock(sock
, p
, recvlen
);
1353 case 0: /* orderly shutdown */
1357 if (len
== recvlen
) {
1358 DBG("app context data received");
1360 } else if (len
< 0) {
1361 DBG("Receive failed from lttng-sessiond with errno %d", (int) -len
);
1362 if (len
== -ECONNRESET
) {
1363 ERR("%s remote end closed connection", sock_info
->name
);
1370 DBG("incorrect app context data message size: %zd", len
);
1375 /* Put : between provider and ctxname. */
1376 p
[lum
->u
.context
.u
.app_ctx
.provider_name_len
- 1] = ':';
1377 args
.app_context
.ctxname
= ctxstr
;
1384 ret
= ops
->cmd(lum
->handle
, lum
->cmd
,
1385 (unsigned long) &lum
->u
,
1391 case LTTNG_UST_ABI_COUNTER
:
1395 len
= ustcomm_recv_counter_from_sessiond(sock
,
1396 &counter_data
, lum
->u
.counter
.len
);
1398 case 0: /* orderly shutdown */
1402 if (len
== lum
->u
.counter
.len
) {
1403 DBG("counter data received");
1405 } else if (len
< 0) {
1406 DBG("Receive failed from lttng-sessiond with errno %d", (int) -len
);
1407 if (len
== -ECONNRESET
) {
1408 ERR("%s remote end closed connection", sock_info
->name
);
1415 DBG("incorrect counter data message size: %zd", len
);
1420 args
.counter
.counter_data
= counter_data
;
1422 ret
= ops
->cmd(lum
->handle
, lum
->cmd
,
1423 (unsigned long) &lum
->u
,
1427 free(args
.counter
.counter_data
);
1430 case LTTNG_UST_ABI_COUNTER_GLOBAL
:
1432 /* Receive shm_fd */
1433 ret
= ustcomm_recv_counter_shm_from_sessiond(sock
,
1434 &args
.counter_shm
.shm_fd
);
1440 ret
= ops
->cmd(lum
->handle
, lum
->cmd
,
1441 (unsigned long) &lum
->u
,
1445 if (args
.counter_shm
.shm_fd
>= 0) {
1448 lttng_ust_lock_fd_tracker();
1449 close_ret
= close(args
.counter_shm
.shm_fd
);
1450 lttng_ust_unlock_fd_tracker();
1451 args
.counter_shm
.shm_fd
= -1;
1457 case LTTNG_UST_ABI_COUNTER_CPU
:
1459 /* Receive shm_fd */
1460 ret
= ustcomm_recv_counter_shm_from_sessiond(sock
,
1461 &args
.counter_shm
.shm_fd
);
1467 ret
= ops
->cmd(lum
->handle
, lum
->cmd
,
1468 (unsigned long) &lum
->u
,
1472 if (args
.counter_shm
.shm_fd
>= 0) {
1475 lttng_ust_lock_fd_tracker();
1476 close_ret
= close(args
.counter_shm
.shm_fd
);
1477 lttng_ust_unlock_fd_tracker();
1478 args
.counter_shm
.shm_fd
= -1;
1484 case LTTNG_UST_ABI_EVENT_NOTIFIER_CREATE
:
1486 /* Receive struct lttng_ust_event_notifier */
1487 struct lttng_ust_abi_event_notifier event_notifier
;
1489 if (sizeof(event_notifier
) != lum
->u
.event_notifier
.len
) {
1490 DBG("incorrect event notifier data message size: %u", lum
->u
.event_notifier
.len
);
1494 len
= ustcomm_recv_unix_sock(sock
, &event_notifier
, sizeof(event_notifier
));
1496 case 0: /* orderly shutdown */
1500 if (len
== sizeof(event_notifier
)) {
1501 DBG("event notifier data received");
1503 } else if (len
< 0) {
1504 DBG("Receive failed from lttng-sessiond with errno %d", (int) -len
);
1505 if (len
== -ECONNRESET
) {
1506 ERR("%s remote end closed connection", sock_info
->name
);
1513 DBG("incorrect event notifier data message size: %zd", len
);
1519 ret
= ops
->cmd(lum
->handle
, lum
->cmd
,
1520 (unsigned long) &event_notifier
,
1529 ret
= ops
->cmd(lum
->handle
, lum
->cmd
,
1530 (unsigned long) &lum
->u
,
1537 prepare_cmd_reply(&lur
, lum
->handle
, lum
->cmd
, ret
);
1541 case LTTNG_UST_ABI_TRACER_VERSION
:
1542 lur
.u
.version
= lum
->u
.version
;
1544 case LTTNG_UST_ABI_TRACEPOINT_LIST_GET
:
1545 memcpy(&lur
.u
.tracepoint
, &lum
->u
.tracepoint
, sizeof(lur
.u
.tracepoint
));
1549 DBG("Return value: %d", lur
.ret_val
);
1554 * Performed delayed statedump operations outside of the UST
1555 * lock. We need to take the dynamic loader lock before we take
1556 * the UST lock internally within handle_pending_statedump().
1558 handle_pending_statedump(sock_info
);
1561 ret
= -LTTNG_UST_ERR_EXITING
;
1565 ret
= send_reply(sock
, &lur
);
1567 DBG("error sending reply");
1572 * LTTNG_UST_TRACEPOINT_FIELD_LIST_GET needs to send the field
1575 if (lur
.ret_code
== LTTNG_UST_OK
) {
1577 case LTTNG_UST_ABI_TRACEPOINT_FIELD_LIST_GET
:
1578 len
= ustcomm_send_unix_sock(sock
,
1579 &args
.field_list
.entry
,
1580 sizeof(args
.field_list
.entry
));
1585 if (len
!= sizeof(args
.field_list
.entry
)) {
1599 void cleanup_sock_info(struct sock_info
*sock_info
, int exiting
)
1603 if (sock_info
->root_handle
!= -1) {
1604 ret
= lttng_ust_abi_objd_unref(sock_info
->root_handle
, 1);
1606 ERR("Error unref root handle");
1608 sock_info
->root_handle
= -1;
1613 * wait_shm_mmap, socket and notify socket are used by listener
1614 * threads outside of the ust lock, so we cannot tear them down
1615 * ourselves, because we cannot join on these threads. Leave
1616 * responsibility of cleaning up these resources to the OS
1622 sock_info
->registration_done
= 0;
1623 sock_info
->initial_statedump_done
= 0;
1625 if (sock_info
->socket
!= -1) {
1626 ret
= ustcomm_close_unix_sock(sock_info
->socket
);
1628 ERR("Error closing ust cmd socket");
1630 sock_info
->socket
= -1;
1632 if (sock_info
->notify_socket
!= -1) {
1633 ret
= ustcomm_close_unix_sock(sock_info
->notify_socket
);
1635 ERR("Error closing ust notify socket");
1637 sock_info
->notify_socket
= -1;
1639 if (sock_info
->wait_shm_mmap
) {
1642 page_size
= LTTNG_UST_PAGE_SIZE
;
1643 if (page_size
<= 0) {
1647 PERROR("Error in sysconf(_SC_PAGE_SIZE)");
1649 ret
= munmap(sock_info
->wait_shm_mmap
, page_size
);
1651 ERR("Error unmapping wait shm");
1654 sock_info
->wait_shm_mmap
= NULL
;
1659 int wait_shm_open(struct sock_info
*sock_info
, int flags
, mode_t mode
)
1661 if (sock_info
->wait_shm_is_file
)
1662 return open(sock_info
->wait_shm_path
, flags
, mode
);
1664 return shm_open(sock_info
->wait_shm_path
, flags
, mode
);
1668 * Using fork to set umask in the child process (not multi-thread safe).
1669 * We deal with the shm_open vs ftruncate race (happening when the
1670 * sessiond owns the shm and does not let everybody modify it, to ensure
1671 * safety against shm_unlink) by simply letting the mmap fail and
1672 * retrying after a few seconds.
1673 * For global shm, everybody has rw access to it until the sessiond
1677 int get_wait_shm(struct sock_info
*sock_info
, size_t mmap_size
)
1679 int wait_shm_fd
, ret
;
1683 * Try to open read-only.
1685 wait_shm_fd
= wait_shm_open(sock_info
, O_RDONLY
, 0);
1686 if (wait_shm_fd
>= 0) {
1689 size_t bytes_read
= 0;
1692 * Try to read the fd. If unable to do so, try opening
1696 len
= read(wait_shm_fd
,
1697 &((char *) &tmp_read
)[bytes_read
],
1698 sizeof(tmp_read
) - bytes_read
);
1702 } while ((len
< 0 && errno
== EINTR
)
1703 || (len
> 0 && bytes_read
< sizeof(tmp_read
)));
1704 if (bytes_read
!= sizeof(tmp_read
)) {
1705 ret
= close(wait_shm_fd
);
1707 ERR("close wait_shm_fd");
1712 } else if (wait_shm_fd
< 0 && errno
!= ENOENT
) {
1714 * Real-only open did not work, and it's not because the
1715 * entry was not present. It's a failure that prohibits
1718 ERR("Error opening shm %s", sock_info
->wait_shm_path
);
1724 * If the open failed because the file did not exist, or because
1725 * the file was not truncated yet, try creating it ourself.
1727 URCU_TLS(lttng_ust_nest_count
)++;
1729 URCU_TLS(lttng_ust_nest_count
)--;
1731 int status
, wait_ret
;
1734 * Parent: wait for child to return, in which case the
1735 * shared memory map will have been created.
1737 wait_ret
= waitpid(pid
, &status
, 0);
1738 if (wait_ret
< 0 || !WIFEXITED(status
) || WEXITSTATUS(status
) != 0) {
1743 * Try to open read-only again after creation.
1745 wait_shm_fd
= wait_shm_open(sock_info
, O_RDONLY
, 0);
1746 if (wait_shm_fd
< 0) {
1748 * Real-only open did not work. It's a failure
1749 * that prohibits using shm.
1751 ERR("Error opening shm %s", sock_info
->wait_shm_path
);
1755 } else if (pid
== 0) {
1759 create_mode
= S_IRUSR
| S_IWUSR
| S_IRGRP
;
1760 if (sock_info
->multi_user
)
1761 create_mode
|= S_IROTH
| S_IWGRP
| S_IWOTH
;
1763 * We're alone in a child process, so we can modify the
1764 * process-wide umask.
1766 umask(~create_mode
);
1768 * Try creating shm (or get rw access).
1769 * We don't do an exclusive open, because we allow other
1770 * processes to create+ftruncate it concurrently.
1772 wait_shm_fd
= wait_shm_open(sock_info
,
1773 O_RDWR
| O_CREAT
, create_mode
);
1774 if (wait_shm_fd
>= 0) {
1775 ret
= ftruncate(wait_shm_fd
, mmap_size
);
1777 PERROR("ftruncate");
1778 _exit(EXIT_FAILURE
);
1780 _exit(EXIT_SUCCESS
);
1783 * For local shm, we need to have rw access to accept
1784 * opening it: this means the local sessiond will be
1785 * able to wake us up. For global shm, we open it even
1786 * if rw access is not granted, because the root.root
1787 * sessiond will be able to override all rights and wake
1790 if (!sock_info
->multi_user
&& errno
!= EACCES
) {
1791 ERR("Error opening shm %s", sock_info
->wait_shm_path
);
1792 _exit(EXIT_FAILURE
);
1795 * The shm exists, but we cannot open it RW. Report
1798 _exit(EXIT_SUCCESS
);
1803 if (wait_shm_fd
>= 0 && !sock_info
->multi_user
) {
1804 struct stat statbuf
;
1807 * Ensure that our user is the owner of the shm file for
1808 * local shm. If we do not own the file, it means our
1809 * sessiond will not have access to wake us up (there is
1810 * probably a rogue process trying to fake our
1811 * sessiond). Fallback to polling method in this case.
1813 ret
= fstat(wait_shm_fd
, &statbuf
);
1818 if (statbuf
.st_uid
!= getuid())
1824 ret
= close(wait_shm_fd
);
1826 PERROR("Error closing fd");
1832 char *get_map_shm(struct sock_info
*sock_info
)
1835 int wait_shm_fd
, ret
;
1836 char *wait_shm_mmap
;
1838 page_size
= sysconf(_SC_PAGE_SIZE
);
1839 if (page_size
<= 0) {
1843 PERROR("Error in sysconf(_SC_PAGE_SIZE)");
1847 lttng_ust_lock_fd_tracker();
1848 wait_shm_fd
= get_wait_shm(sock_info
, page_size
);
1849 if (wait_shm_fd
< 0) {
1850 lttng_ust_unlock_fd_tracker();
1854 ret
= lttng_ust_add_fd_to_tracker(wait_shm_fd
);
1856 ret
= close(wait_shm_fd
);
1858 PERROR("Error closing fd");
1860 lttng_ust_unlock_fd_tracker();
1865 lttng_ust_unlock_fd_tracker();
1867 wait_shm_mmap
= mmap(NULL
, page_size
, PROT_READ
,
1868 MAP_SHARED
, wait_shm_fd
, 0);
1870 /* close shm fd immediately after taking the mmap reference */
1871 lttng_ust_lock_fd_tracker();
1872 ret
= close(wait_shm_fd
);
1874 lttng_ust_delete_fd_from_tracker(wait_shm_fd
);
1876 PERROR("Error closing fd");
1878 lttng_ust_unlock_fd_tracker();
1880 if (wait_shm_mmap
== MAP_FAILED
) {
1881 DBG("mmap error (can be caused by race with sessiond). Fallback to poll mode.");
1884 return wait_shm_mmap
;
1891 void wait_for_sessiond(struct sock_info
*sock_info
)
1893 /* Use ust_lock to check if we should quit. */
1897 if (wait_poll_fallback
) {
1902 assert(sock_info
->wait_shm_mmap
);
1904 DBG("Waiting for %s apps sessiond", sock_info
->name
);
1905 /* Wait for futex wakeup */
1906 while (!uatomic_read((int32_t *) sock_info
->wait_shm_mmap
)) {
1907 if (!lttng_ust_futex_async((int32_t *) sock_info
->wait_shm_mmap
, FUTEX_WAIT
, 0, NULL
, NULL
, 0)) {
1909 * Prior queued wakeups queued by unrelated code
1910 * using the same address can cause futex wait to
1911 * return 0 even through the futex value is still
1912 * 0 (spurious wakeups). Check the value again
1913 * in user-space to validate whether it really
1920 /* Value already changed. */
1923 /* Retry if interrupted by signal. */
1924 break; /* Get out of switch. Check again. */
1926 wait_poll_fallback
= 1;
1928 "Linux kernels 2.6.33 to 3.0 (with the exception of stable versions) "
1929 "do not support FUTEX_WAKE on read-only memory mappings correctly. "
1930 "Please upgrade your kernel "
1931 "(fix is commit 9ea71503a8ed9184d2d0b8ccc4d269d05f7940ae in Linux kernel "
1932 "mainline). LTTng-UST will use polling mode fallback.");
1933 if (lttng_ust_logging_debug_enabled())
1951 * This thread does not allocate any resource, except within
1952 * handle_message, within mutex protection. This mutex protects against
1954 * The other moment it allocates resources is at socket connection, which
1955 * is also protected by the mutex.
1958 void *ust_listener_thread(void *arg
)
1960 struct sock_info
*sock_info
= arg
;
1961 int sock
, ret
, prev_connect_failed
= 0, has_waited
= 0, fd
;
1964 lttng_ust_common_init_thread(0);
1966 * If available, add '-ust' to the end of this thread's
1969 ret
= lttng_ust_setustprocname();
1971 ERR("Unable to set UST process name");
1974 /* Restart trying to connect to the session daemon */
1976 if (prev_connect_failed
) {
1977 /* Wait for sessiond availability with pipe */
1978 wait_for_sessiond(sock_info
);
1982 * Sleep for 5 seconds before retrying after a
1983 * sequence of failure / wait / failure. This
1984 * deals with a killed or broken session daemon.
1990 prev_connect_failed
= 0;
1997 if (sock_info
->socket
!= -1) {
1998 /* FD tracker is updated by ustcomm_close_unix_sock() */
1999 ret
= ustcomm_close_unix_sock(sock_info
->socket
);
2001 ERR("Error closing %s ust cmd socket",
2004 sock_info
->socket
= -1;
2006 if (sock_info
->notify_socket
!= -1) {
2007 /* FD tracker is updated by ustcomm_close_unix_sock() */
2008 ret
= ustcomm_close_unix_sock(sock_info
->notify_socket
);
2010 ERR("Error closing %s ust notify socket",
2013 sock_info
->notify_socket
= -1;
2018 * Register. We need to perform both connect and sending
2019 * registration message before doing the next connect otherwise
2020 * we may reach unix socket connect queue max limits and block
2021 * on the 2nd connect while the session daemon is awaiting the
2022 * first connect registration message.
2024 /* Connect cmd socket */
2025 lttng_ust_lock_fd_tracker();
2026 ret
= ustcomm_connect_unix_sock(sock_info
->sock_path
,
2027 get_connect_sock_timeout());
2029 lttng_ust_unlock_fd_tracker();
2030 DBG("Info: sessiond not accepting connections to %s apps socket", sock_info
->name
);
2031 prev_connect_failed
= 1;
2034 * If we cannot find the sessiond daemon, don't delay
2035 * constructor execution.
2037 ret
= handle_register_failed(sock_info
);
2043 ret
= lttng_ust_add_fd_to_tracker(fd
);
2047 PERROR("close on sock_info->socket");
2050 lttng_ust_unlock_fd_tracker();
2055 sock_info
->socket
= ret
;
2056 lttng_ust_unlock_fd_tracker();
2060 * Unlock/relock ust lock because connect is blocking (with
2061 * timeout). Don't delay constructors on the ust lock for too
2069 * Create only one root handle per listener thread for the whole
2070 * process lifetime, so we ensure we get ID which is statically
2071 * assigned to the root handle.
2073 if (sock_info
->root_handle
== -1) {
2074 ret
= lttng_abi_create_root_handle();
2076 ERR("Error creating root handle");
2079 sock_info
->root_handle
= ret
;
2082 ret
= register_to_sessiond(sock_info
->socket
, LTTNG_UST_CTL_SOCKET_CMD
,
2083 sock_info
->procname
);
2085 ERR("Error registering to %s ust cmd socket",
2087 prev_connect_failed
= 1;
2089 * If we cannot register to the sessiond daemon, don't
2090 * delay constructor execution.
2092 ret
= handle_register_failed(sock_info
);
2100 * Unlock/relock ust lock because connect is blocking (with
2101 * timeout). Don't delay constructors on the ust lock for too
2108 /* Connect notify socket */
2109 lttng_ust_lock_fd_tracker();
2110 ret
= ustcomm_connect_unix_sock(sock_info
->sock_path
,
2111 get_connect_sock_timeout());
2113 lttng_ust_unlock_fd_tracker();
2114 DBG("Info: sessiond not accepting connections to %s apps socket", sock_info
->name
);
2115 prev_connect_failed
= 1;
2118 * If we cannot find the sessiond daemon, don't delay
2119 * constructor execution.
2121 ret
= handle_register_failed(sock_info
);
2128 ret
= lttng_ust_add_fd_to_tracker(fd
);
2132 PERROR("close on sock_info->notify_socket");
2135 lttng_ust_unlock_fd_tracker();
2140 sock_info
->notify_socket
= ret
;
2141 lttng_ust_unlock_fd_tracker();
2145 * Unlock/relock ust lock because connect is blocking (with
2146 * timeout). Don't delay constructors on the ust lock for too
2153 timeout
= get_notify_sock_timeout();
2156 * Give at least 10ms to sessiond to reply to
2161 ret
= ustcomm_setsockopt_rcv_timeout(sock_info
->notify_socket
,
2164 WARN("Error setting socket receive timeout");
2166 ret
= ustcomm_setsockopt_snd_timeout(sock_info
->notify_socket
,
2169 WARN("Error setting socket send timeout");
2171 } else if (timeout
< -1) {
2172 WARN("Unsupported timeout value %ld", timeout
);
2175 ret
= register_to_sessiond(sock_info
->notify_socket
,
2176 LTTNG_UST_CTL_SOCKET_NOTIFY
, sock_info
->procname
);
2178 ERR("Error registering to %s ust notify socket",
2180 prev_connect_failed
= 1;
2182 * If we cannot register to the sessiond daemon, don't
2183 * delay constructor execution.
2185 ret
= handle_register_failed(sock_info
);
2190 sock
= sock_info
->socket
;
2196 struct ustcomm_ust_msg lum
;
2198 len
= ustcomm_recv_unix_sock(sock
, &lum
, sizeof(lum
));
2200 case 0: /* orderly shutdown */
2201 DBG("%s lttng-sessiond has performed an orderly shutdown", sock_info
->name
);
2206 * Either sessiond has shutdown or refused us by closing the socket.
2207 * In either case, we don't want to delay construction execution,
2208 * and we need to wait before retry.
2210 prev_connect_failed
= 1;
2212 * If we cannot register to the sessiond daemon, don't
2213 * delay constructor execution.
2215 ret
= handle_register_failed(sock_info
);
2220 print_cmd(lum
.cmd
, lum
.handle
);
2221 ret
= handle_message(sock_info
, sock
, &lum
);
2223 ERR("Error handling message for %s socket",
2226 * Close socket if protocol error is
2234 DBG("Receive failed from lttng-sessiond with errno %d", (int) -len
);
2236 DBG("incorrect message size (%s socket): %zd", sock_info
->name
, len
);
2238 if (len
== -ECONNRESET
) {
2239 DBG("%s remote end closed connection", sock_info
->name
);
2250 /* Cleanup socket handles before trying to reconnect */
2251 lttng_ust_abi_objd_table_owner_cleanup(sock_info
);
2253 goto restart
; /* try to reconnect */
2258 pthread_mutex_lock(&ust_exit_mutex
);
2259 sock_info
->thread_active
= 0;
2260 pthread_mutex_unlock(&ust_exit_mutex
);
2265 * Weak symbol to call when the ust malloc wrapper is not loaded.
2267 __attribute__((weak
))
2268 void lttng_ust_libc_wrapper_malloc_ctor(void)
2273 * Use a symbol of the previous ABI to detect if liblttng-ust.so.0 is loaded in
2274 * the current process.
2276 #define LTTNG_UST_SONAME_0_SYM "ltt_probe_register"
2279 void lttng_ust_check_soname_0(void)
2281 if (!dlsym(RTLD_DEFAULT
, LTTNG_UST_SONAME_0_SYM
))
2284 CRIT("Incompatible library ABIs detected within the same process. "
2285 "The process is likely linked against different major soname of LTTng-UST which is unsupported. "
2286 "The detection was triggered by lookup of ABI 0 symbol \"%s\" in the Global Symbol Table\n",
2287 LTTNG_UST_SONAME_0_SYM
);
2291 * Expose a canary symbol of the previous ABI to ensure we catch uses of a
2292 * liblttng-ust.so.0 dlopen'd after .so.1 has been loaded. Use a different
2293 * symbol than the detection code to ensure we don't detect ourself.
2295 * This scheme will only work on systems where the global symbol table has
2296 * priority when resolving the symbols of a dlopened shared object, which is
2297 * the case on Linux but not on FreeBSD.
2299 void init_usterr(void);
2300 void init_usterr(void)
2302 CRIT("Incompatible library ABIs detected within the same process. "
2303 "The process is likely linked against different major soname of LTTng-UST which is unsupported. "
2304 "The detection was triggered by canary symbol \"%s\"\n", __func__
);
2308 * sessiond monitoring thread: monitor presence of global and per-user
2309 * sessiond by polling the application common named pipe.
2312 void lttng_ust_ctor(void)
2313 __attribute__((constructor
));
2315 void lttng_ust_ctor(void)
2317 struct timespec constructor_timeout
;
2318 sigset_t sig_all_blocked
, orig_parent_mask
;
2319 pthread_attr_t thread_attr
;
2324 if (uatomic_xchg(&initialized
, 1) == 1)
2328 * Fixup interdependency between TLS allocation mutex (which happens
2329 * to be the dynamic linker mutex) and ust_lock, taken within
2332 lttng_ust_common_init_thread(0);
2334 lttng_ust_loaded
= 1;
2337 * Check if we find a symbol of the previous ABI in the current process
2338 * as different ABIs of liblttng-ust can't co-exist in a process. If we
2339 * do so, emit a critical log message which will also abort if the
2340 * LTTNG_UST_ABORT_ON_CRITICAL environment variable is set.
2342 lttng_ust_check_soname_0();
2345 * We need to ensure that the liblttng-ust library is not unloaded to avoid
2346 * the unloading of code used by the ust_listener_threads as we can not
2347 * reliably know when they exited. To do that, manually load
2348 * liblttng-ust.so to increment the dynamic loader's internal refcount for
2349 * this library so it never becomes zero, thus never gets unloaded from the
2350 * address space of the process. Since we are already running in the
2351 * constructor of the LTTNG_UST_LIB_SONAME library, calling dlopen will
2352 * simply increment the refcount and no additional work is needed by the
2353 * dynamic loader as the shared library is already loaded in the address
2354 * space. As a safe guard, we use the RTLD_NODELETE flag to prevent
2355 * unloading of the UST library if its refcount becomes zero (which should
2356 * never happen). Do the return value check but discard the handle at the
2357 * end of the function as it's not needed.
2359 handle
= dlopen(LTTNG_UST_LIB_SONAME
, RTLD_LAZY
| RTLD_NODELETE
);
2361 ERR("dlopen of liblttng-ust shared library (%s).", LTTNG_UST_LIB_SONAME
);
2363 DBG("dlopened liblttng-ust shared library (%s).", LTTNG_UST_LIB_SONAME
);
2367 * We want precise control over the order in which we construct
2368 * our sub-libraries vs starting to receive commands from
2369 * sessiond (otherwise leading to errors when trying to create
2370 * sessiond before the init functions are completed).
2374 * Both the logging and getenv lazy-initialization uses getenv()
2375 * internally and thus needs to be explicitly initialized in
2376 * liblttng-ust before we start any threads as an unsuspecting normally
2377 * single threaded application using liblttng-ust could be using
2378 * setenv() which is not thread-safe.
2380 lttng_ust_logging_init();
2381 lttng_ust_getenv_init();
2383 /* Call the liblttng-ust-common constructor. */
2384 lttng_ust_common_ctor();
2386 lttng_ust_tp_init();
2387 lttng_ust_statedump_init();
2388 lttng_ust_ring_buffer_clients_init();
2389 lttng_ust_counter_clients_init();
2390 lttng_perf_counter_init();
2392 * Invoke ust malloc wrapper init before starting other threads.
2394 lttng_ust_libc_wrapper_malloc_ctor();
2396 timeout_mode
= get_constructor_timeout(&constructor_timeout
);
2398 get_allow_blocking();
2400 ret
= sem_init(&constructor_wait
, 0, 0);
2405 ret
= setup_ust_apps();
2407 assert(ust_app
.allowed
== 0);
2408 DBG("ust_app setup returned %d", ret
);
2410 ret
= setup_global_apps();
2412 assert(global_apps
.allowed
== 0);
2413 DBG("global apps setup returned %d", ret
);
2416 ret
= setup_local_apps();
2418 assert(local_apps
.allowed
== 0);
2419 DBG("local apps setup returned %d", ret
);
2422 /* A new thread created by pthread_create inherits the signal mask
2423 * from the parent. To avoid any signal being received by the
2424 * listener thread, we block all signals temporarily in the parent,
2425 * while we create the listener thread.
2427 sigfillset(&sig_all_blocked
);
2428 ret
= pthread_sigmask(SIG_SETMASK
, &sig_all_blocked
, &orig_parent_mask
);
2430 ERR("pthread_sigmask: %s", strerror(ret
));
2433 ret
= pthread_attr_init(&thread_attr
);
2435 ERR("pthread_attr_init: %s", strerror(ret
));
2437 ret
= pthread_attr_setdetachstate(&thread_attr
, PTHREAD_CREATE_DETACHED
);
2439 ERR("pthread_attr_setdetachstate: %s", strerror(ret
));
2442 if (ust_app
.allowed
) {
2443 pthread_mutex_lock(&ust_exit_mutex
);
2444 ret
= pthread_create(&ust_app
.ust_listener
, &thread_attr
,
2445 ust_listener_thread
, &ust_app
);
2447 ERR("pthread_create ust_app: %s", strerror(ret
));
2449 ust_app
.thread_active
= 1;
2450 pthread_mutex_unlock(&ust_exit_mutex
);
2452 handle_register_done(&ust_app
);
2455 if (global_apps
.allowed
) {
2456 pthread_mutex_lock(&ust_exit_mutex
);
2457 ret
= pthread_create(&global_apps
.ust_listener
, &thread_attr
,
2458 ust_listener_thread
, &global_apps
);
2460 ERR("pthread_create global: %s", strerror(ret
));
2462 global_apps
.thread_active
= 1;
2463 pthread_mutex_unlock(&ust_exit_mutex
);
2465 handle_register_done(&global_apps
);
2468 if (local_apps
.allowed
) {
2469 pthread_mutex_lock(&ust_exit_mutex
);
2470 ret
= pthread_create(&local_apps
.ust_listener
, &thread_attr
,
2471 ust_listener_thread
, &local_apps
);
2473 ERR("pthread_create local: %s", strerror(ret
));
2475 local_apps
.thread_active
= 1;
2476 pthread_mutex_unlock(&ust_exit_mutex
);
2478 handle_register_done(&local_apps
);
2480 ret
= pthread_attr_destroy(&thread_attr
);
2482 ERR("pthread_attr_destroy: %s", strerror(ret
));
2485 /* Restore original signal mask in parent */
2486 ret
= pthread_sigmask(SIG_SETMASK
, &orig_parent_mask
, NULL
);
2488 ERR("pthread_sigmask: %s", strerror(ret
));
2491 switch (timeout_mode
) {
2492 case 1: /* timeout wait */
2494 ret
= sem_timedwait(&constructor_wait
,
2495 &constructor_timeout
);
2496 } while (ret
< 0 && errno
== EINTR
);
2500 ERR("Timed out waiting for lttng-sessiond");
2503 PERROR("sem_timedwait");
2506 ERR("Unexpected error \"%s\" returned by sem_timedwait",
2511 case -1:/* wait forever */
2513 ret
= sem_wait(&constructor_wait
);
2514 } while (ret
< 0 && errno
== EINTR
);
2521 ERR("Unexpected error \"%s\" returned by sem_wait",
2526 case 0: /* no timeout */
2532 void lttng_ust_cleanup(int exiting
)
2534 cleanup_sock_info(&ust_app
, exiting
);
2535 cleanup_sock_info(&global_apps
, exiting
);
2536 cleanup_sock_info(&local_apps
, exiting
);
2537 ust_app
.allowed
= 0;
2538 local_apps
.allowed
= 0;
2539 global_apps
.allowed
= 0;
2541 * The teardown in this function all affect data structures
2542 * accessed under the UST lock by the listener thread. This
2543 * lock, along with the lttng_ust_comm_should_quit flag, ensure
2544 * that none of these threads are accessing this data at this
2547 lttng_ust_abi_exit();
2548 lttng_ust_abi_events_exit();
2549 lttng_perf_counter_exit();
2550 lttng_ust_ring_buffer_clients_exit();
2551 lttng_ust_counter_clients_exit();
2552 lttng_ust_statedump_destroy();
2553 lttng_ust_tp_exit();
2555 /* Reinitialize values for fork */
2556 sem_count
= sem_count_initial_value
;
2557 lttng_ust_comm_should_quit
= 0;
2563 void lttng_ust_exit(void)
2564 __attribute__((destructor
));
2566 void lttng_ust_exit(void)
2571 * Using pthread_cancel here because:
2572 * A) we don't want to hang application teardown.
2573 * B) the thread is not allocating any resource.
2577 * Require the communication thread to quit. Synchronize with
2578 * mutexes to ensure it is not in a mutex critical section when
2579 * pthread_cancel is later called.
2582 lttng_ust_comm_should_quit
= 1;
2585 pthread_mutex_lock(&ust_exit_mutex
);
2586 /* cancel threads */
2587 if (ust_app
.thread_active
) {
2588 ret
= pthread_cancel(ust_app
.ust_listener
);
2590 ERR("Error cancelling ust listener thread: %s",
2593 ust_app
.thread_active
= 0;
2596 if (global_apps
.thread_active
) {
2597 ret
= pthread_cancel(global_apps
.ust_listener
);
2599 ERR("Error cancelling global ust listener thread: %s",
2602 global_apps
.thread_active
= 0;
2605 if (local_apps
.thread_active
) {
2606 ret
= pthread_cancel(local_apps
.ust_listener
);
2608 ERR("Error cancelling local ust listener thread: %s",
2611 local_apps
.thread_active
= 0;
2614 pthread_mutex_unlock(&ust_exit_mutex
);
2617 * Do NOT join threads: use of sys_futex makes it impossible to
2618 * join the threads without using async-cancel, but async-cancel
2619 * is delivered by a signal, which could hit the target thread
2620 * anywhere in its code path, including while the ust_lock() is
2621 * held, causing a deadlock for the other thread. Let the OS
2622 * cleanup the threads if there are stalled in a syscall.
2624 lttng_ust_cleanup(1);
2628 void ust_context_ns_reset(void)
2630 lttng_context_pid_ns_reset();
2631 lttng_context_cgroup_ns_reset();
2632 lttng_context_ipc_ns_reset();
2633 lttng_context_mnt_ns_reset();
2634 lttng_context_net_ns_reset();
2635 lttng_context_user_ns_reset();
2636 lttng_context_time_ns_reset();
2637 lttng_context_uts_ns_reset();
2641 void ust_context_vuids_reset(void)
2643 lttng_context_vuid_reset();
2644 lttng_context_veuid_reset();
2645 lttng_context_vsuid_reset();
2649 void ust_context_vgids_reset(void)
2651 lttng_context_vgid_reset();
2652 lttng_context_vegid_reset();
2653 lttng_context_vsgid_reset();
2657 * We exclude the worker threads across fork and clone (except
2658 * CLONE_VM), because these system calls only keep the forking thread
2659 * running in the child. Therefore, we don't want to call fork or clone
2660 * in the middle of an tracepoint or ust tracing state modification.
2661 * Holding this mutex protects these structures across fork and clone.
2663 void lttng_ust_before_fork(sigset_t
*save_sigset
)
2666 * Disable signals. This is to avoid that the child intervenes
2667 * before it is properly setup for tracing. It is safer to
2668 * disable all signals, because then we know we are not breaking
2669 * anything by restoring the original mask.
2674 /* Allocate lttng-ust TLS. */
2675 lttng_ust_common_init_thread(0);
2677 if (URCU_TLS(lttng_ust_nest_count
))
2679 /* Disable signals */
2680 sigfillset(&all_sigs
);
2681 ret
= sigprocmask(SIG_BLOCK
, &all_sigs
, save_sigset
);
2683 PERROR("sigprocmask");
2686 pthread_mutex_lock(&ust_fork_mutex
);
2689 lttng_ust_urcu_before_fork();
2690 lttng_ust_lock_fd_tracker();
2694 static void ust_after_fork_common(sigset_t
*restore_sigset
)
2698 DBG("process %d", getpid());
2699 lttng_perf_unlock();
2700 lttng_ust_unlock_fd_tracker();
2703 pthread_mutex_unlock(&ust_fork_mutex
);
2705 /* Restore signals */
2706 ret
= sigprocmask(SIG_SETMASK
, restore_sigset
, NULL
);
2708 PERROR("sigprocmask");
2712 void lttng_ust_after_fork_parent(sigset_t
*restore_sigset
)
2714 if (URCU_TLS(lttng_ust_nest_count
))
2716 DBG("process %d", getpid());
2717 lttng_ust_urcu_after_fork_parent();
2718 /* Release mutexes and re-enable signals */
2719 ust_after_fork_common(restore_sigset
);
2723 * After fork, in the child, we need to cleanup all the leftover state,
2724 * except the worker thread which already magically disappeared thanks
2725 * to the weird Linux fork semantics. After tyding up, we call
2726 * lttng_ust_ctor() again to start over as a new PID.
2728 * This is meant for forks() that have tracing in the child between the
2729 * fork and following exec call (if there is any).
2731 void lttng_ust_after_fork_child(sigset_t
*restore_sigset
)
2733 if (URCU_TLS(lttng_ust_nest_count
))
2735 lttng_context_vpid_reset();
2736 lttng_context_vtid_reset();
2737 lttng_ust_context_procname_reset();
2738 ust_context_ns_reset();
2739 ust_context_vuids_reset();
2740 ust_context_vgids_reset();
2741 DBG("process %d", getpid());
2742 /* Release urcu mutexes */
2743 lttng_ust_urcu_after_fork_child();
2744 lttng_ust_cleanup(0);
2745 /* Release mutexes and re-enable signals */
2746 ust_after_fork_common(restore_sigset
);
2750 void lttng_ust_after_setns(void)
2752 ust_context_ns_reset();
2753 ust_context_vuids_reset();
2754 ust_context_vgids_reset();
2757 void lttng_ust_after_unshare(void)
2759 ust_context_ns_reset();
2760 ust_context_vuids_reset();
2761 ust_context_vgids_reset();
2764 void lttng_ust_after_setuid(void)
2766 ust_context_vuids_reset();
2769 void lttng_ust_after_seteuid(void)
2771 ust_context_vuids_reset();
2774 void lttng_ust_after_setreuid(void)
2776 ust_context_vuids_reset();
2779 void lttng_ust_after_setresuid(void)
2781 ust_context_vuids_reset();
2784 void lttng_ust_after_setgid(void)
2786 ust_context_vgids_reset();
2789 void lttng_ust_after_setegid(void)
2791 ust_context_vgids_reset();
2794 void lttng_ust_after_setregid(void)
2796 ust_context_vgids_reset();
2799 void lttng_ust_after_setresgid(void)
2801 ust_context_vgids_reset();
2804 void lttng_ust_sockinfo_session_enabled(void *owner
)
2806 struct sock_info
*sock_info
= owner
;
2807 sock_info
->statedump_pending
= 1;