4 * Holds LTTng per-session event registry.
6 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; only
11 * version 2.1 of the License.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 #include <linux/module.h>
24 #include <linux/mutex.h>
25 #include <linux/sched.h>
26 #include <linux/slab.h>
27 #include <linux/jiffies.h>
28 #include <linux/utsname.h>
29 #include <linux/err.h>
30 #include <linux/seq_file.h>
31 #include <linux/file.h>
32 #include <linux/anon_inodes.h>
33 #include "wrapper/file.h"
34 #include <linux/jhash.h>
36 #include "wrapper/uuid.h"
37 #include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */
38 #include "wrapper/random.h"
39 #include "wrapper/tracepoint.h"
40 #include "wrapper/list.h"
41 #include "lttng-kernel-version.h"
42 #include "lttng-events.h"
43 #include "lttng-tracer.h"
44 #include "lttng-abi-old.h"
46 #define METADATA_CACHE_DEFAULT_SIZE 4096
48 static LIST_HEAD(sessions
);
49 static LIST_HEAD(lttng_transport_list
);
51 * Protect the sessions and metadata caches.
53 static DEFINE_MUTEX(sessions_mutex
);
54 static struct kmem_cache
*event_cache
;
56 static void lttng_session_lazy_sync_enablers(struct lttng_session
*session
);
57 static void lttng_session_sync_enablers(struct lttng_session
*session
);
58 static void lttng_enabler_destroy(struct lttng_enabler
*enabler
);
60 static void _lttng_event_destroy(struct lttng_event
*event
);
61 static void _lttng_channel_destroy(struct lttng_channel
*chan
);
62 static int _lttng_event_unregister(struct lttng_event
*event
);
64 int _lttng_event_metadata_statedump(struct lttng_session
*session
,
65 struct lttng_channel
*chan
,
66 struct lttng_event
*event
);
68 int _lttng_session_metadata_statedump(struct lttng_session
*session
);
70 void _lttng_metadata_channel_hangup(struct lttng_metadata_stream
*stream
);
72 void synchronize_trace(void)
75 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0))
76 #ifdef CONFIG_PREEMPT_RT_FULL
79 #else /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */
80 #ifdef CONFIG_PREEMPT_RT
83 #endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */
86 void lttng_lock_sessions(void)
88 mutex_lock(&sessions_mutex
);
91 void lttng_unlock_sessions(void)
93 mutex_unlock(&sessions_mutex
);
97 * Called with sessions lock held.
99 int lttng_session_active(void)
101 struct lttng_session
*iter
;
103 list_for_each_entry(iter
, &sessions
, list
) {
110 struct lttng_session
*lttng_session_create(void)
112 struct lttng_session
*session
;
113 struct lttng_metadata_cache
*metadata_cache
;
116 mutex_lock(&sessions_mutex
);
117 session
= kzalloc(sizeof(struct lttng_session
), GFP_KERNEL
);
120 INIT_LIST_HEAD(&session
->chan
);
121 INIT_LIST_HEAD(&session
->events
);
122 uuid_le_gen(&session
->uuid
);
124 metadata_cache
= kzalloc(sizeof(struct lttng_metadata_cache
),
127 goto err_free_session
;
128 metadata_cache
->data
= kzalloc(METADATA_CACHE_DEFAULT_SIZE
,
130 if (!metadata_cache
->data
)
132 metadata_cache
->cache_alloc
= METADATA_CACHE_DEFAULT_SIZE
;
133 kref_init(&metadata_cache
->refcount
);
134 session
->metadata_cache
= metadata_cache
;
135 INIT_LIST_HEAD(&metadata_cache
->metadata_stream
);
136 memcpy(&metadata_cache
->uuid
, &session
->uuid
,
137 sizeof(metadata_cache
->uuid
));
138 INIT_LIST_HEAD(&session
->enablers_head
);
139 for (i
= 0; i
< LTTNG_EVENT_HT_SIZE
; i
++)
140 INIT_HLIST_HEAD(&session
->events_ht
.table
[i
]);
141 list_add(&session
->list
, &sessions
);
142 mutex_unlock(&sessions_mutex
);
146 kfree(metadata_cache
);
150 mutex_unlock(&sessions_mutex
);
154 void metadata_cache_destroy(struct kref
*kref
)
156 struct lttng_metadata_cache
*cache
=
157 container_of(kref
, struct lttng_metadata_cache
, refcount
);
162 void lttng_session_destroy(struct lttng_session
*session
)
164 struct lttng_channel
*chan
, *tmpchan
;
165 struct lttng_event
*event
, *tmpevent
;
166 struct lttng_metadata_stream
*metadata_stream
;
167 struct lttng_enabler
*enabler
, *tmpenabler
;
170 mutex_lock(&sessions_mutex
);
171 ACCESS_ONCE(session
->active
) = 0;
172 list_for_each_entry(chan
, &session
->chan
, list
) {
173 ret
= lttng_syscalls_unregister(chan
);
176 list_for_each_entry(event
, &session
->events
, list
) {
177 ret
= _lttng_event_unregister(event
);
180 synchronize_trace(); /* Wait for in-flight events to complete */
181 list_for_each_entry_safe(enabler
, tmpenabler
,
182 &session
->enablers_head
, node
)
183 lttng_enabler_destroy(enabler
);
184 list_for_each_entry_safe(event
, tmpevent
, &session
->events
, list
)
185 _lttng_event_destroy(event
);
186 list_for_each_entry_safe(chan
, tmpchan
, &session
->chan
, list
) {
187 BUG_ON(chan
->channel_type
== METADATA_CHANNEL
);
188 _lttng_channel_destroy(chan
);
190 list_for_each_entry(metadata_stream
, &session
->metadata_cache
->metadata_stream
, list
)
191 _lttng_metadata_channel_hangup(metadata_stream
);
192 if (session
->pid_tracker
)
193 lttng_pid_tracker_destroy(session
->pid_tracker
);
194 kref_put(&session
->metadata_cache
->refcount
, metadata_cache_destroy
);
195 list_del(&session
->list
);
196 mutex_unlock(&sessions_mutex
);
200 int lttng_session_enable(struct lttng_session
*session
)
203 struct lttng_channel
*chan
;
205 mutex_lock(&sessions_mutex
);
206 if (session
->active
) {
211 /* Set transient enabler state to "enabled" */
215 * Snapshot the number of events per channel to know the type of header
218 list_for_each_entry(chan
, &session
->chan
, list
) {
219 if (chan
->header_type
)
220 continue; /* don't change it if session stop/restart */
221 if (chan
->free_event_id
< 31)
222 chan
->header_type
= 1; /* compact */
224 chan
->header_type
= 2; /* large */
227 /* We need to sync enablers with session before activation. */
228 lttng_session_sync_enablers(session
);
230 ACCESS_ONCE(session
->active
) = 1;
231 ACCESS_ONCE(session
->been_active
) = 1;
232 ret
= _lttng_session_metadata_statedump(session
);
234 ACCESS_ONCE(session
->active
) = 0;
237 ret
= lttng_statedump_start(session
);
239 ACCESS_ONCE(session
->active
) = 0;
241 mutex_unlock(&sessions_mutex
);
245 int lttng_session_disable(struct lttng_session
*session
)
249 mutex_lock(&sessions_mutex
);
250 if (!session
->active
) {
254 ACCESS_ONCE(session
->active
) = 0;
256 /* Set transient enabler state to "disabled" */
258 lttng_session_sync_enablers(session
);
260 mutex_unlock(&sessions_mutex
);
264 int lttng_channel_enable(struct lttng_channel
*channel
)
268 mutex_lock(&sessions_mutex
);
269 if (channel
->channel_type
== METADATA_CHANNEL
) {
273 if (channel
->enabled
) {
277 /* Set transient enabler state to "enabled" */
279 lttng_session_sync_enablers(channel
->session
);
280 /* Set atomically the state to "enabled" */
281 ACCESS_ONCE(channel
->enabled
) = 1;
283 mutex_unlock(&sessions_mutex
);
287 int lttng_channel_disable(struct lttng_channel
*channel
)
291 mutex_lock(&sessions_mutex
);
292 if (channel
->channel_type
== METADATA_CHANNEL
) {
296 if (!channel
->enabled
) {
300 /* Set atomically the state to "disabled" */
301 ACCESS_ONCE(channel
->enabled
) = 0;
302 /* Set transient enabler state to "enabled" */
304 lttng_session_sync_enablers(channel
->session
);
306 mutex_unlock(&sessions_mutex
);
310 int lttng_event_enable(struct lttng_event
*event
)
314 mutex_lock(&sessions_mutex
);
315 if (event
->chan
->channel_type
== METADATA_CHANNEL
) {
319 if (event
->enabled
) {
323 ACCESS_ONCE(event
->enabled
) = 1;
324 lttng_session_sync_enablers(event
->chan
->session
);
326 mutex_unlock(&sessions_mutex
);
330 int lttng_event_disable(struct lttng_event
*event
)
334 mutex_lock(&sessions_mutex
);
335 if (event
->chan
->channel_type
== METADATA_CHANNEL
) {
339 if (!event
->enabled
) {
343 ACCESS_ONCE(event
->enabled
) = 0;
344 lttng_session_sync_enablers(event
->chan
->session
);
346 mutex_unlock(&sessions_mutex
);
350 static struct lttng_transport
*lttng_transport_find(const char *name
)
352 struct lttng_transport
*transport
;
354 list_for_each_entry(transport
, <tng_transport_list
, node
) {
355 if (!strcmp(transport
->name
, name
))
361 struct lttng_channel
*lttng_channel_create(struct lttng_session
*session
,
362 const char *transport_name
,
364 size_t subbuf_size
, size_t num_subbuf
,
365 unsigned int switch_timer_interval
,
366 unsigned int read_timer_interval
,
367 enum channel_type channel_type
)
369 struct lttng_channel
*chan
;
370 struct lttng_transport
*transport
= NULL
;
372 mutex_lock(&sessions_mutex
);
373 if (session
->been_active
&& channel_type
!= METADATA_CHANNEL
)
374 goto active
; /* Refuse to add channel to active session */
375 transport
= lttng_transport_find(transport_name
);
377 printk(KERN_WARNING
"LTTng transport %s not found\n",
381 if (!try_module_get(transport
->owner
)) {
382 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
385 chan
= kzalloc(sizeof(struct lttng_channel
), GFP_KERNEL
);
388 chan
->session
= session
;
389 chan
->id
= session
->free_chan_id
++;
390 chan
->ops
= &transport
->ops
;
392 * Note: the channel creation op already writes into the packet
393 * headers. Therefore the "chan" information used as input
394 * should be already accessible.
396 chan
->chan
= transport
->ops
.channel_create(transport_name
,
397 chan
, buf_addr
, subbuf_size
, num_subbuf
,
398 switch_timer_interval
, read_timer_interval
);
403 chan
->transport
= transport
;
404 chan
->channel_type
= channel_type
;
405 list_add(&chan
->list
, &session
->chan
);
406 mutex_unlock(&sessions_mutex
);
413 module_put(transport
->owner
);
416 mutex_unlock(&sessions_mutex
);
421 * Only used internally at session destruction for per-cpu channels, and
422 * when metadata channel is released.
423 * Needs to be called with sessions mutex held.
426 void _lttng_channel_destroy(struct lttng_channel
*chan
)
428 chan
->ops
->channel_destroy(chan
->chan
);
429 module_put(chan
->transport
->owner
);
430 list_del(&chan
->list
);
431 lttng_destroy_context(chan
->ctx
);
435 void lttng_metadata_channel_destroy(struct lttng_channel
*chan
)
437 BUG_ON(chan
->channel_type
!= METADATA_CHANNEL
);
439 /* Protect the metadata cache with the sessions_mutex. */
440 mutex_lock(&sessions_mutex
);
441 _lttng_channel_destroy(chan
);
442 mutex_unlock(&sessions_mutex
);
444 EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy
);
447 void _lttng_metadata_channel_hangup(struct lttng_metadata_stream
*stream
)
449 stream
->finalized
= 1;
450 wake_up_interruptible(&stream
->read_wait
);
454 * Supports event creation while tracing session is active.
455 * Needs to be called with sessions mutex held.
457 struct lttng_event
*_lttng_event_create(struct lttng_channel
*chan
,
458 struct lttng_kernel_event
*event_param
,
460 const struct lttng_event_desc
*event_desc
,
461 enum lttng_kernel_instrumentation itype
)
463 struct lttng_session
*session
= chan
->session
;
464 struct lttng_event
*event
;
465 const char *event_name
;
466 struct hlist_head
*head
;
471 if (chan
->free_event_id
== -1U) {
477 case LTTNG_KERNEL_TRACEPOINT
:
478 event_name
= event_desc
->name
;
480 case LTTNG_KERNEL_KPROBE
:
481 case LTTNG_KERNEL_KRETPROBE
:
482 case LTTNG_KERNEL_FUNCTION
:
483 case LTTNG_KERNEL_NOOP
:
484 case LTTNG_KERNEL_SYSCALL
:
485 event_name
= event_param
->name
;
492 name_len
= strlen(event_name
);
493 hash
= jhash(event_name
, name_len
, 0);
494 head
= &session
->events_ht
.table
[hash
& (LTTNG_EVENT_HT_SIZE
- 1)];
495 hlist_for_each_entry(event
, head
, hlist
) {
496 WARN_ON_ONCE(!event
->desc
);
497 if (!strncmp(event
->desc
->name
, event_name
,
498 LTTNG_KERNEL_SYM_NAME_LEN
- 1)
499 && chan
== event
->chan
) {
505 event
= kmem_cache_zalloc(event_cache
, GFP_KERNEL
);
511 event
->filter
= filter
;
512 event
->id
= chan
->free_event_id
++;
513 event
->instrumentation
= itype
;
514 event
->evtype
= LTTNG_TYPE_EVENT
;
515 INIT_LIST_HEAD(&event
->enablers_ref_head
);
518 case LTTNG_KERNEL_TRACEPOINT
:
519 /* Event will be enabled by enabler sync. */
521 event
->registered
= 0;
522 event
->desc
= lttng_event_get(event_name
);
527 /* Populate lttng_event structure before event registration. */
530 case LTTNG_KERNEL_KPROBE
:
532 event
->registered
= 1;
534 * Populate lttng_event structure before event
538 ret
= lttng_kprobes_register(event_name
,
539 event_param
->u
.kprobe
.symbol_name
,
540 event_param
->u
.kprobe
.offset
,
541 event_param
->u
.kprobe
.addr
,
547 ret
= try_module_get(event
->desc
->owner
);
550 case LTTNG_KERNEL_KRETPROBE
:
552 struct lttng_event
*event_return
;
554 /* kretprobe defines 2 events */
556 event
->registered
= 1;
558 kmem_cache_zalloc(event_cache
, GFP_KERNEL
);
563 event_return
->chan
= chan
;
564 event_return
->filter
= filter
;
565 event_return
->id
= chan
->free_event_id
++;
566 event_return
->enabled
= 1;
567 event_return
->registered
= 1;
568 event_return
->instrumentation
= itype
;
570 * Populate lttng_event structure before kretprobe registration.
573 ret
= lttng_kretprobes_register(event_name
,
574 event_param
->u
.kretprobe
.symbol_name
,
575 event_param
->u
.kretprobe
.offset
,
576 event_param
->u
.kretprobe
.addr
,
577 event
, event_return
);
579 kmem_cache_free(event_cache
, event_return
);
583 /* Take 2 refs on the module: one per event. */
584 ret
= try_module_get(event
->desc
->owner
);
586 ret
= try_module_get(event
->desc
->owner
);
588 ret
= _lttng_event_metadata_statedump(chan
->session
, chan
,
590 WARN_ON_ONCE(ret
> 0);
592 kmem_cache_free(event_cache
, event_return
);
593 module_put(event
->desc
->owner
);
594 module_put(event
->desc
->owner
);
595 goto statedump_error
;
597 list_add(&event_return
->list
, &chan
->session
->events
);
600 case LTTNG_KERNEL_FUNCTION
:
602 event
->registered
= 1;
604 * Populate lttng_event structure before event
608 ret
= lttng_ftrace_register(event_name
,
609 event_param
->u
.ftrace
.symbol_name
,
614 ret
= try_module_get(event
->desc
->owner
);
617 case LTTNG_KERNEL_NOOP
:
618 case LTTNG_KERNEL_SYSCALL
:
620 event
->registered
= 0;
621 event
->desc
= event_desc
;
632 ret
= _lttng_event_metadata_statedump(chan
->session
, chan
, event
);
633 WARN_ON_ONCE(ret
> 0);
635 goto statedump_error
;
637 hlist_add_head(&event
->hlist
, head
);
638 list_add(&event
->list
, &chan
->session
->events
);
639 mutex_unlock(&sessions_mutex
);
643 /* If a statedump error occurs, events will not be readable. */
645 kmem_cache_free(event_cache
, event
);
653 struct lttng_event
*lttng_event_create(struct lttng_channel
*chan
,
654 struct lttng_kernel_event
*event_param
,
656 const struct lttng_event_desc
*event_desc
,
657 enum lttng_kernel_instrumentation itype
)
659 struct lttng_event
*event
;
661 mutex_lock(&sessions_mutex
);
662 event
= _lttng_event_create(chan
, event_param
, filter
, event_desc
,
664 mutex_unlock(&sessions_mutex
);
668 /* Only used for tracepoints for now. */
670 void register_event(struct lttng_event
*event
)
672 const struct lttng_event_desc
*desc
;
675 if (event
->registered
)
679 switch (event
->instrumentation
) {
680 case LTTNG_KERNEL_TRACEPOINT
:
681 ret
= lttng_wrapper_tracepoint_probe_register(desc
->kname
,
682 desc
->probe_callback
,
685 case LTTNG_KERNEL_SYSCALL
:
686 ret
= lttng_syscall_filter_enable(event
->chan
,
689 case LTTNG_KERNEL_KPROBE
:
690 case LTTNG_KERNEL_KRETPROBE
:
691 case LTTNG_KERNEL_FUNCTION
:
692 case LTTNG_KERNEL_NOOP
:
699 event
->registered
= 1;
703 * Only used internally at session destruction.
705 int _lttng_event_unregister(struct lttng_event
*event
)
707 const struct lttng_event_desc
*desc
;
710 if (!event
->registered
)
714 switch (event
->instrumentation
) {
715 case LTTNG_KERNEL_TRACEPOINT
:
716 ret
= lttng_wrapper_tracepoint_probe_unregister(event
->desc
->kname
,
717 event
->desc
->probe_callback
,
720 case LTTNG_KERNEL_KPROBE
:
721 lttng_kprobes_unregister(event
);
724 case LTTNG_KERNEL_KRETPROBE
:
725 lttng_kretprobes_unregister(event
);
728 case LTTNG_KERNEL_FUNCTION
:
729 lttng_ftrace_unregister(event
);
732 case LTTNG_KERNEL_SYSCALL
:
733 ret
= lttng_syscall_filter_disable(event
->chan
,
736 case LTTNG_KERNEL_NOOP
:
743 event
->registered
= 0;
748 * Only used internally at session destruction.
751 void _lttng_event_destroy(struct lttng_event
*event
)
753 switch (event
->instrumentation
) {
754 case LTTNG_KERNEL_TRACEPOINT
:
755 lttng_event_put(event
->desc
);
757 case LTTNG_KERNEL_KPROBE
:
758 module_put(event
->desc
->owner
);
759 lttng_kprobes_destroy_private(event
);
761 case LTTNG_KERNEL_KRETPROBE
:
762 module_put(event
->desc
->owner
);
763 lttng_kretprobes_destroy_private(event
);
765 case LTTNG_KERNEL_FUNCTION
:
766 module_put(event
->desc
->owner
);
767 lttng_ftrace_destroy_private(event
);
769 case LTTNG_KERNEL_NOOP
:
770 case LTTNG_KERNEL_SYSCALL
:
775 list_del(&event
->list
);
776 lttng_destroy_context(event
->ctx
);
777 kmem_cache_free(event_cache
, event
);
780 int lttng_session_track_pid(struct lttng_session
*session
, int pid
)
786 mutex_lock(&sessions_mutex
);
788 /* track all pids: destroy tracker. */
789 if (session
->pid_tracker
) {
790 struct lttng_pid_tracker
*lpf
;
792 lpf
= session
->pid_tracker
;
793 rcu_assign_pointer(session
->pid_tracker
, NULL
);
795 lttng_pid_tracker_destroy(lpf
);
799 if (!session
->pid_tracker
) {
800 struct lttng_pid_tracker
*lpf
;
802 lpf
= lttng_pid_tracker_create();
807 ret
= lttng_pid_tracker_add(lpf
, pid
);
808 rcu_assign_pointer(session
->pid_tracker
, lpf
);
810 ret
= lttng_pid_tracker_add(session
->pid_tracker
, pid
);
814 mutex_unlock(&sessions_mutex
);
818 int lttng_session_untrack_pid(struct lttng_session
*session
, int pid
)
824 mutex_lock(&sessions_mutex
);
826 /* untrack all pids: replace by empty tracker. */
827 struct lttng_pid_tracker
*old_lpf
= session
->pid_tracker
;
828 struct lttng_pid_tracker
*lpf
;
830 lpf
= lttng_pid_tracker_create();
835 rcu_assign_pointer(session
->pid_tracker
, lpf
);
838 lttng_pid_tracker_destroy(old_lpf
);
841 if (!session
->pid_tracker
) {
845 ret
= lttng_pid_tracker_del(session
->pid_tracker
, pid
);
848 mutex_unlock(&sessions_mutex
);
853 void *pid_list_start(struct seq_file
*m
, loff_t
*pos
)
855 struct lttng_session
*session
= m
->private;
856 struct lttng_pid_tracker
*lpf
;
857 struct lttng_pid_hash_node
*e
;
860 mutex_lock(&sessions_mutex
);
861 lpf
= session
->pid_tracker
;
863 for (i
= 0; i
< LTTNG_PID_TABLE_SIZE
; i
++) {
864 struct hlist_head
*head
= &lpf
->pid_hash
[i
];
866 lttng_hlist_for_each_entry(e
, head
, hlist
) {
872 /* PID tracker disabled. */
873 if (iter
>= *pos
&& iter
== 0) {
874 return session
; /* empty tracker */
882 /* Called with sessions_mutex held. */
884 void *pid_list_next(struct seq_file
*m
, void *p
, loff_t
*ppos
)
886 struct lttng_session
*session
= m
->private;
887 struct lttng_pid_tracker
*lpf
;
888 struct lttng_pid_hash_node
*e
;
892 lpf
= session
->pid_tracker
;
894 for (i
= 0; i
< LTTNG_PID_TABLE_SIZE
; i
++) {
895 struct hlist_head
*head
= &lpf
->pid_hash
[i
];
897 lttng_hlist_for_each_entry(e
, head
, hlist
) {
903 /* PID tracker disabled. */
904 if (iter
>= *ppos
&& iter
== 0)
905 return session
; /* empty tracker */
914 void pid_list_stop(struct seq_file
*m
, void *p
)
916 mutex_unlock(&sessions_mutex
);
920 int pid_list_show(struct seq_file
*m
, void *p
)
924 if (p
== m
->private) {
925 /* Tracker disabled. */
928 const struct lttng_pid_hash_node
*e
= p
;
930 pid
= lttng_pid_tracker_get_node_pid(e
);
932 seq_printf(m
, "process { pid = %d; };\n", pid
);
937 const struct seq_operations lttng_tracker_pids_list_seq_ops
= {
938 .start
= pid_list_start
,
939 .next
= pid_list_next
,
940 .stop
= pid_list_stop
,
941 .show
= pid_list_show
,
945 int lttng_tracker_pids_list_open(struct inode
*inode
, struct file
*file
)
947 return seq_open(file
, <tng_tracker_pids_list_seq_ops
);
951 int lttng_tracker_pids_list_release(struct inode
*inode
, struct file
*file
)
953 struct seq_file
*m
= file
->private_data
;
954 struct lttng_session
*session
= m
->private;
957 WARN_ON_ONCE(!session
);
958 ret
= seq_release(inode
, file
);
964 const struct file_operations lttng_tracker_pids_list_fops
= {
965 .owner
= THIS_MODULE
,
966 .open
= lttng_tracker_pids_list_open
,
969 .release
= lttng_tracker_pids_list_release
,
972 int lttng_session_list_tracker_pids(struct lttng_session
*session
)
974 struct file
*tracker_pids_list_file
;
978 file_fd
= lttng_get_unused_fd();
984 tracker_pids_list_file
= anon_inode_getfile("[lttng_tracker_pids_list]",
985 <tng_tracker_pids_list_fops
,
987 if (IS_ERR(tracker_pids_list_file
)) {
988 ret
= PTR_ERR(tracker_pids_list_file
);
991 ret
= lttng_tracker_pids_list_fops
.open(NULL
, tracker_pids_list_file
);
994 m
= tracker_pids_list_file
->private_data
;
995 m
->private = session
;
996 fd_install(file_fd
, tracker_pids_list_file
);
997 atomic_long_inc(&session
->file
->f_count
);
1002 fput(tracker_pids_list_file
);
1004 put_unused_fd(file_fd
);
1010 * Enabler management.
1013 int lttng_match_enabler_wildcard(const char *desc_name
,
1016 /* Compare excluding final '*' */
1017 if (strncmp(desc_name
, name
, strlen(name
) - 1))
1023 int lttng_match_enabler_name(const char *desc_name
,
1026 if (strcmp(desc_name
, name
))
1032 int lttng_desc_match_enabler(const struct lttng_event_desc
*desc
,
1033 struct lttng_enabler
*enabler
)
1035 const char *desc_name
, *enabler_name
;
1037 enabler_name
= enabler
->event_param
.name
;
1038 switch (enabler
->event_param
.instrumentation
) {
1039 case LTTNG_KERNEL_TRACEPOINT
:
1040 desc_name
= desc
->name
;
1042 case LTTNG_KERNEL_SYSCALL
:
1043 desc_name
= desc
->name
;
1044 if (!strncmp(desc_name
, "compat_", strlen("compat_")))
1045 desc_name
+= strlen("compat_");
1046 if (!strncmp(desc_name
, "syscall_exit_",
1047 strlen("syscall_exit_"))) {
1048 desc_name
+= strlen("syscall_exit_");
1049 } else if (!strncmp(desc_name
, "syscall_entry_",
1050 strlen("syscall_entry_"))) {
1051 desc_name
+= strlen("syscall_entry_");
1061 switch (enabler
->type
) {
1062 case LTTNG_ENABLER_WILDCARD
:
1063 return lttng_match_enabler_wildcard(desc_name
, enabler_name
);
1064 case LTTNG_ENABLER_NAME
:
1065 return lttng_match_enabler_name(desc_name
, enabler_name
);
1072 int lttng_event_match_enabler(struct lttng_event
*event
,
1073 struct lttng_enabler
*enabler
)
1075 if (enabler
->event_param
.instrumentation
!= event
->instrumentation
)
1077 if (lttng_desc_match_enabler(event
->desc
, enabler
)
1078 && event
->chan
== enabler
->chan
)
1085 struct lttng_enabler_ref
*lttng_event_enabler_ref(struct lttng_event
*event
,
1086 struct lttng_enabler
*enabler
)
1088 struct lttng_enabler_ref
*enabler_ref
;
1090 list_for_each_entry(enabler_ref
,
1091 &event
->enablers_ref_head
, node
) {
1092 if (enabler_ref
->ref
== enabler
)
1099 void lttng_create_tracepoint_if_missing(struct lttng_enabler
*enabler
)
1101 struct lttng_session
*session
= enabler
->chan
->session
;
1102 struct lttng_probe_desc
*probe_desc
;
1103 const struct lttng_event_desc
*desc
;
1105 struct list_head
*probe_list
;
1107 probe_list
= lttng_get_probe_list_head();
1109 * For each probe event, if we find that a probe event matches
1110 * our enabler, create an associated lttng_event if not
1113 list_for_each_entry(probe_desc
, probe_list
, head
) {
1114 for (i
= 0; i
< probe_desc
->nr_events
; i
++) {
1116 struct hlist_head
*head
;
1117 const char *event_name
;
1120 struct lttng_event
*event
;
1122 desc
= probe_desc
->event_desc
[i
];
1123 if (!lttng_desc_match_enabler(desc
, enabler
))
1125 event_name
= desc
->name
;
1126 name_len
= strlen(event_name
);
1129 * Check if already created.
1131 hash
= jhash(event_name
, name_len
, 0);
1132 head
= &session
->events_ht
.table
[hash
& (LTTNG_EVENT_HT_SIZE
- 1)];
1133 hlist_for_each_entry(event
, head
, hlist
) {
1134 if (event
->desc
== desc
1135 && event
->chan
== enabler
->chan
)
1142 * We need to create an event for this
1145 event
= _lttng_event_create(enabler
->chan
,
1147 LTTNG_KERNEL_TRACEPOINT
);
1149 printk(KERN_INFO
"Unable to create event %s\n",
1150 probe_desc
->event_desc
[i
]->name
);
1157 void lttng_create_syscall_if_missing(struct lttng_enabler
*enabler
)
1161 ret
= lttng_syscalls_register(enabler
->chan
, NULL
);
1166 * Create struct lttng_event if it is missing and present in the list of
1167 * tracepoint probes.
1168 * Should be called with sessions mutex held.
1171 void lttng_create_event_if_missing(struct lttng_enabler
*enabler
)
1173 switch (enabler
->event_param
.instrumentation
) {
1174 case LTTNG_KERNEL_TRACEPOINT
:
1175 lttng_create_tracepoint_if_missing(enabler
);
1177 case LTTNG_KERNEL_SYSCALL
:
1178 lttng_create_syscall_if_missing(enabler
);
1187 * Create events associated with an enabler (if not already present),
1188 * and add backward reference from the event to the enabler.
1189 * Should be called with sessions mutex held.
1192 int lttng_enabler_ref_events(struct lttng_enabler
*enabler
)
1194 struct lttng_session
*session
= enabler
->chan
->session
;
1195 struct lttng_event
*event
;
1197 /* First ensure that probe events are created for this enabler. */
1198 lttng_create_event_if_missing(enabler
);
1200 /* For each event matching enabler in session event list. */
1201 list_for_each_entry(event
, &session
->events
, list
) {
1202 struct lttng_enabler_ref
*enabler_ref
;
1204 if (!lttng_event_match_enabler(event
, enabler
))
1206 enabler_ref
= lttng_event_enabler_ref(event
, enabler
);
1209 * If no backward ref, create it.
1210 * Add backward ref from event to enabler.
1212 enabler_ref
= kzalloc(sizeof(*enabler_ref
), GFP_KERNEL
);
1215 enabler_ref
->ref
= enabler
;
1216 list_add(&enabler_ref
->node
,
1217 &event
->enablers_ref_head
);
1220 /* TODO: merge event context. */
1226 * Called at module load: connect the probe on all enablers matching
1228 * Called with sessions lock held.
1230 int lttng_fix_pending_events(void)
1232 struct lttng_session
*session
;
1234 list_for_each_entry(session
, &sessions
, list
)
1235 lttng_session_lazy_sync_enablers(session
);
1239 struct lttng_enabler
*lttng_enabler_create(enum lttng_enabler_type type
,
1240 struct lttng_kernel_event
*event_param
,
1241 struct lttng_channel
*chan
)
1243 struct lttng_enabler
*enabler
;
1245 enabler
= kzalloc(sizeof(*enabler
), GFP_KERNEL
);
1248 enabler
->type
= type
;
1249 memcpy(&enabler
->event_param
, event_param
,
1250 sizeof(enabler
->event_param
));
1251 enabler
->chan
= chan
;
1253 enabler
->enabled
= 1;
1254 enabler
->evtype
= LTTNG_TYPE_ENABLER
;
1255 mutex_lock(&sessions_mutex
);
1256 list_add(&enabler
->node
, &enabler
->chan
->session
->enablers_head
);
1257 lttng_session_lazy_sync_enablers(enabler
->chan
->session
);
1258 mutex_unlock(&sessions_mutex
);
1262 int lttng_enabler_enable(struct lttng_enabler
*enabler
)
1264 mutex_lock(&sessions_mutex
);
1265 enabler
->enabled
= 1;
1266 lttng_session_lazy_sync_enablers(enabler
->chan
->session
);
1267 mutex_unlock(&sessions_mutex
);
1271 int lttng_enabler_disable(struct lttng_enabler
*enabler
)
1273 mutex_lock(&sessions_mutex
);
1274 enabler
->enabled
= 0;
1275 lttng_session_lazy_sync_enablers(enabler
->chan
->session
);
1276 mutex_unlock(&sessions_mutex
);
1280 int lttng_enabler_attach_context(struct lttng_enabler
*enabler
,
1281 struct lttng_kernel_context
*context_param
)
1287 void lttng_enabler_destroy(struct lttng_enabler
*enabler
)
1289 /* Destroy contexts */
1290 lttng_destroy_context(enabler
->ctx
);
1292 list_del(&enabler
->node
);
1297 * lttng_session_sync_enablers should be called just before starting a
1299 * Should be called with sessions mutex held.
1302 void lttng_session_sync_enablers(struct lttng_session
*session
)
1304 struct lttng_enabler
*enabler
;
1305 struct lttng_event
*event
;
1307 list_for_each_entry(enabler
, &session
->enablers_head
, node
)
1308 lttng_enabler_ref_events(enabler
);
1310 * For each event, if at least one of its enablers is enabled,
1311 * and its channel and session transient states are enabled, we
1312 * enable the event, else we disable it.
1314 list_for_each_entry(event
, &session
->events
, list
) {
1315 struct lttng_enabler_ref
*enabler_ref
;
1318 switch (event
->instrumentation
) {
1319 case LTTNG_KERNEL_TRACEPOINT
:
1320 case LTTNG_KERNEL_SYSCALL
:
1322 list_for_each_entry(enabler_ref
,
1323 &event
->enablers_ref_head
, node
) {
1324 if (enabler_ref
->ref
->enabled
) {
1331 /* Not handled with lazy sync. */
1335 * Enabled state is based on union of enablers, with
1336 * intesection of session and channel transient enable
1339 enabled
= enabled
&& session
->tstate
&& event
->chan
->tstate
;
1341 ACCESS_ONCE(event
->enabled
) = enabled
;
1343 * Sync tracepoint registration with event enabled
1347 register_event(event
);
1349 _lttng_event_unregister(event
);
1355 * Apply enablers to session events, adding events to session if need
1356 * be. It is required after each modification applied to an active
1357 * session, and right before session "start".
1358 * "lazy" sync means we only sync if required.
1359 * Should be called with sessions mutex held.
1362 void lttng_session_lazy_sync_enablers(struct lttng_session
*session
)
1364 /* We can skip if session is not active */
1365 if (!session
->active
)
1367 lttng_session_sync_enablers(session
);
1371 * Serialize at most one packet worth of metadata into a metadata
1373 * We have exclusive access to our metadata buffer (protected by the
1374 * sessions_mutex), so we can do racy operations such as looking for
1375 * remaining space left in packet and write, since mutual exclusion
1376 * protects us from concurrent writes.
1377 * Returns the number of bytes written in the channel, 0 if no data
1378 * was written and a negative value on error.
1380 int lttng_metadata_output_channel(struct lttng_metadata_stream
*stream
,
1381 struct channel
*chan
)
1383 struct lib_ring_buffer_ctx ctx
;
1385 size_t len
, reserve_len
;
1388 * Ensure we support mutiple get_next / put sequences followed
1389 * by put_next. The metadata stream lock internally protects
1390 * reading the metadata cache. It can indeed be read
1391 * concurrently by "get_next_subbuf" and "flush" operations on
1392 * the buffer invoked by different processes.
1394 mutex_lock(&stream
->lock
);
1395 WARN_ON(stream
->metadata_in
< stream
->metadata_out
);
1396 if (stream
->metadata_in
!= stream
->metadata_out
)
1399 len
= stream
->metadata_cache
->metadata_written
-
1400 stream
->metadata_in
;
1403 reserve_len
= min_t(size_t,
1404 stream
->transport
->ops
.packet_avail_size(chan
),
1406 lib_ring_buffer_ctx_init(&ctx
, chan
, NULL
, reserve_len
,
1409 * If reservation failed, return an error to the caller.
1411 ret
= stream
->transport
->ops
.event_reserve(&ctx
, 0);
1413 printk(KERN_WARNING
"LTTng: Metadata event reservation failed\n");
1416 stream
->transport
->ops
.event_write(&ctx
,
1417 stream
->metadata_cache
->data
+ stream
->metadata_in
,
1419 stream
->transport
->ops
.event_commit(&ctx
);
1420 stream
->metadata_in
+= reserve_len
;
1424 mutex_unlock(&stream
->lock
);
1429 * Write the metadata to the metadata cache.
1430 * Must be called with sessions_mutex held.
1432 int lttng_metadata_printf(struct lttng_session
*session
,
1433 const char *fmt
, ...)
1438 struct lttng_metadata_stream
*stream
;
1440 WARN_ON_ONCE(!ACCESS_ONCE(session
->active
));
1443 str
= kvasprintf(GFP_KERNEL
, fmt
, ap
);
1449 if (session
->metadata_cache
->metadata_written
+ len
>
1450 session
->metadata_cache
->cache_alloc
) {
1451 char *tmp_cache_realloc
;
1452 unsigned int tmp_cache_alloc_size
;
1454 tmp_cache_alloc_size
= max_t(unsigned int,
1455 session
->metadata_cache
->cache_alloc
+ len
,
1456 session
->metadata_cache
->cache_alloc
<< 1);
1457 tmp_cache_realloc
= krealloc(session
->metadata_cache
->data
,
1458 tmp_cache_alloc_size
, GFP_KERNEL
);
1459 if (!tmp_cache_realloc
)
1461 session
->metadata_cache
->cache_alloc
= tmp_cache_alloc_size
;
1462 session
->metadata_cache
->data
= tmp_cache_realloc
;
1464 memcpy(session
->metadata_cache
->data
+
1465 session
->metadata_cache
->metadata_written
,
1467 session
->metadata_cache
->metadata_written
+= len
;
1470 list_for_each_entry(stream
, &session
->metadata_cache
->metadata_stream
, list
)
1471 wake_up_interruptible(&stream
->read_wait
);
1481 * Must be called with sessions_mutex held.
1484 int _lttng_field_statedump(struct lttng_session
*session
,
1485 const struct lttng_event_field
*field
)
1489 switch (field
->type
.atype
) {
1491 ret
= lttng_metadata_printf(session
,
1492 " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n",
1493 field
->type
.u
.basic
.integer
.size
,
1494 field
->type
.u
.basic
.integer
.alignment
,
1495 field
->type
.u
.basic
.integer
.signedness
,
1496 (field
->type
.u
.basic
.integer
.encoding
== lttng_encode_none
)
1498 : (field
->type
.u
.basic
.integer
.encoding
== lttng_encode_UTF8
)
1501 field
->type
.u
.basic
.integer
.base
,
1503 field
->type
.u
.basic
.integer
.reverse_byte_order
? " byte_order = le;" : "",
1505 field
->type
.u
.basic
.integer
.reverse_byte_order
? " byte_order = be;" : "",
1510 ret
= lttng_metadata_printf(session
,
1512 field
->type
.u
.basic
.enumeration
.name
,
1517 const struct lttng_basic_type
*elem_type
;
1519 elem_type
= &field
->type
.u
.array
.elem_type
;
1520 ret
= lttng_metadata_printf(session
,
1521 " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n",
1522 elem_type
->u
.basic
.integer
.size
,
1523 elem_type
->u
.basic
.integer
.alignment
,
1524 elem_type
->u
.basic
.integer
.signedness
,
1525 (elem_type
->u
.basic
.integer
.encoding
== lttng_encode_none
)
1527 : (elem_type
->u
.basic
.integer
.encoding
== lttng_encode_UTF8
)
1530 elem_type
->u
.basic
.integer
.base
,
1532 elem_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = le;" : "",
1534 elem_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = be;" : "",
1536 field
->name
, field
->type
.u
.array
.length
);
1539 case atype_sequence
:
1541 const struct lttng_basic_type
*elem_type
;
1542 const struct lttng_basic_type
*length_type
;
1544 elem_type
= &field
->type
.u
.sequence
.elem_type
;
1545 length_type
= &field
->type
.u
.sequence
.length_type
;
1546 ret
= lttng_metadata_printf(session
,
1547 " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n",
1548 length_type
->u
.basic
.integer
.size
,
1549 (unsigned int) length_type
->u
.basic
.integer
.alignment
,
1550 length_type
->u
.basic
.integer
.signedness
,
1551 (length_type
->u
.basic
.integer
.encoding
== lttng_encode_none
)
1553 : ((length_type
->u
.basic
.integer
.encoding
== lttng_encode_UTF8
)
1556 length_type
->u
.basic
.integer
.base
,
1558 length_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = le;" : "",
1560 length_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = be;" : "",
1566 ret
= lttng_metadata_printf(session
,
1567 " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n",
1568 elem_type
->u
.basic
.integer
.size
,
1569 (unsigned int) elem_type
->u
.basic
.integer
.alignment
,
1570 elem_type
->u
.basic
.integer
.signedness
,
1571 (elem_type
->u
.basic
.integer
.encoding
== lttng_encode_none
)
1573 : ((elem_type
->u
.basic
.integer
.encoding
== lttng_encode_UTF8
)
1576 elem_type
->u
.basic
.integer
.base
,
1578 elem_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = le;" : "",
1580 elem_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = be;" : "",
1588 /* Default encoding is UTF8 */
1589 ret
= lttng_metadata_printf(session
,
1591 field
->type
.u
.basic
.string
.encoding
== lttng_encode_ASCII
?
1592 " { encoding = ASCII; }" : "",
1603 int _lttng_context_metadata_statedump(struct lttng_session
*session
,
1604 struct lttng_ctx
*ctx
)
1611 for (i
= 0; i
< ctx
->nr_fields
; i
++) {
1612 const struct lttng_ctx_field
*field
= &ctx
->fields
[i
];
1614 ret
= _lttng_field_statedump(session
, &field
->event_field
);
1622 int _lttng_fields_metadata_statedump(struct lttng_session
*session
,
1623 struct lttng_event
*event
)
1625 const struct lttng_event_desc
*desc
= event
->desc
;
1629 for (i
= 0; i
< desc
->nr_fields
; i
++) {
1630 const struct lttng_event_field
*field
= &desc
->fields
[i
];
1632 ret
= _lttng_field_statedump(session
, field
);
1640 * Must be called with sessions_mutex held.
1643 int _lttng_event_metadata_statedump(struct lttng_session
*session
,
1644 struct lttng_channel
*chan
,
1645 struct lttng_event
*event
)
1649 if (event
->metadata_dumped
|| !ACCESS_ONCE(session
->active
))
1651 if (chan
->channel_type
== METADATA_CHANNEL
)
1654 ret
= lttng_metadata_printf(session
,
1658 " stream_id = %u;\n",
1666 ret
= lttng_metadata_printf(session
,
1667 " context := struct {\n");
1671 ret
= _lttng_context_metadata_statedump(session
, event
->ctx
);
1675 ret
= lttng_metadata_printf(session
,
1681 ret
= lttng_metadata_printf(session
,
1682 " fields := struct {\n"
1687 ret
= _lttng_fields_metadata_statedump(session
, event
);
1692 * LTTng space reservation can only reserve multiples of the
1695 ret
= lttng_metadata_printf(session
,
1701 event
->metadata_dumped
= 1;
1708 * Must be called with sessions_mutex held.
1711 int _lttng_channel_metadata_statedump(struct lttng_session
*session
,
1712 struct lttng_channel
*chan
)
1716 if (chan
->metadata_dumped
|| !ACCESS_ONCE(session
->active
))
1719 if (chan
->channel_type
== METADATA_CHANNEL
)
1722 WARN_ON_ONCE(!chan
->header_type
);
1723 ret
= lttng_metadata_printf(session
,
1726 " event.header := %s;\n"
1727 " packet.context := struct packet_context;\n",
1729 chan
->header_type
== 1 ? "struct event_header_compact" :
1730 "struct event_header_large");
1735 ret
= lttng_metadata_printf(session
,
1736 " event.context := struct {\n");
1740 ret
= _lttng_context_metadata_statedump(session
, chan
->ctx
);
1744 ret
= lttng_metadata_printf(session
,
1750 ret
= lttng_metadata_printf(session
,
1753 chan
->metadata_dumped
= 1;
1759 * Must be called with sessions_mutex held.
1762 int _lttng_stream_packet_context_declare(struct lttng_session
*session
)
1764 return lttng_metadata_printf(session
,
1765 "struct packet_context {\n"
1766 " uint64_clock_monotonic_t timestamp_begin;\n"
1767 " uint64_clock_monotonic_t timestamp_end;\n"
1768 " uint64_t content_size;\n"
1769 " uint64_t packet_size;\n"
1770 " unsigned long events_discarded;\n"
1771 " uint32_t cpu_id;\n"
1778 * id: range: 0 - 30.
1779 * id 31 is reserved to indicate an extended header.
1782 * id: range: 0 - 65534.
1783 * id 65535 is reserved to indicate an extended header.
1785 * Must be called with sessions_mutex held.
1788 int _lttng_event_header_declare(struct lttng_session
*session
)
1790 return lttng_metadata_printf(session
,
1791 "struct event_header_compact {\n"
1792 " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n"
1795 " uint27_clock_monotonic_t timestamp;\n"
1799 " uint64_clock_monotonic_t timestamp;\n"
1804 "struct event_header_large {\n"
1805 " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n"
1808 " uint32_clock_monotonic_t timestamp;\n"
1812 " uint64_clock_monotonic_t timestamp;\n"
1816 lttng_alignof(uint32_t) * CHAR_BIT
,
1817 lttng_alignof(uint16_t) * CHAR_BIT
1822 * Approximation of NTP time of day to clock monotonic correlation,
1823 * taken at start of trace.
1824 * Yes, this is only an approximation. Yes, we can (and will) do better
1825 * in future versions.
1828 uint64_t measure_clock_offset(void)
1830 uint64_t offset
, monotonic
[2], realtime
;
1831 struct timespec rts
= { 0, 0 };
1832 unsigned long flags
;
1834 /* Disable interrupts to increase correlation precision. */
1835 local_irq_save(flags
);
1836 monotonic
[0] = trace_clock_read64();
1837 getnstimeofday(&rts
);
1838 monotonic
[1] = trace_clock_read64();
1839 local_irq_restore(flags
);
1841 offset
= (monotonic
[0] + monotonic
[1]) >> 1;
1842 realtime
= (uint64_t) rts
.tv_sec
* NSEC_PER_SEC
;
1843 realtime
+= rts
.tv_nsec
;
1844 offset
= realtime
- offset
;
1849 * Output metadata into this session's metadata buffers.
1850 * Must be called with sessions_mutex held.
1853 int _lttng_session_metadata_statedump(struct lttng_session
*session
)
1855 unsigned char *uuid_c
= session
->uuid
.b
;
1856 unsigned char uuid_s
[37], clock_uuid_s
[BOOT_ID_LEN
];
1857 struct lttng_channel
*chan
;
1858 struct lttng_event
*event
;
1861 if (!ACCESS_ONCE(session
->active
))
1863 if (session
->metadata_dumped
)
1866 snprintf(uuid_s
, sizeof(uuid_s
),
1867 "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
1868 uuid_c
[0], uuid_c
[1], uuid_c
[2], uuid_c
[3],
1869 uuid_c
[4], uuid_c
[5], uuid_c
[6], uuid_c
[7],
1870 uuid_c
[8], uuid_c
[9], uuid_c
[10], uuid_c
[11],
1871 uuid_c
[12], uuid_c
[13], uuid_c
[14], uuid_c
[15]);
1873 ret
= lttng_metadata_printf(session
,
1874 "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n"
1875 "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n"
1876 "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n"
1877 "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n"
1878 "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n"
1879 "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n"
1880 "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n"
1886 " byte_order = %s;\n"
1887 " packet.header := struct {\n"
1888 " uint32_t magic;\n"
1889 " uint8_t uuid[16];\n"
1890 " uint32_t stream_id;\n"
1893 lttng_alignof(uint8_t) * CHAR_BIT
,
1894 lttng_alignof(uint16_t) * CHAR_BIT
,
1895 lttng_alignof(uint32_t) * CHAR_BIT
,
1896 lttng_alignof(uint64_t) * CHAR_BIT
,
1897 sizeof(unsigned long) * CHAR_BIT
,
1898 lttng_alignof(unsigned long) * CHAR_BIT
,
1911 ret
= lttng_metadata_printf(session
,
1913 " hostname = \"%s\";\n"
1914 " domain = \"kernel\";\n"
1915 " sysname = \"%s\";\n"
1916 " kernel_release = \"%s\";\n"
1917 " kernel_version = \"%s\";\n"
1918 " tracer_name = \"lttng-modules\";\n"
1919 " tracer_major = %d;\n"
1920 " tracer_minor = %d;\n"
1921 " tracer_patchlevel = %d;\n"
1923 current
->nsproxy
->uts_ns
->name
.nodename
,
1927 LTTNG_MODULES_MAJOR_VERSION
,
1928 LTTNG_MODULES_MINOR_VERSION
,
1929 LTTNG_MODULES_PATCHLEVEL_VERSION
1934 ret
= lttng_metadata_printf(session
,
1942 if (!trace_clock_uuid(clock_uuid_s
)) {
1943 ret
= lttng_metadata_printf(session
,
1944 " uuid = \"%s\";\n",
1951 ret
= lttng_metadata_printf(session
,
1952 " description = \"Monotonic Clock\";\n"
1953 " freq = %llu; /* Frequency, in Hz */\n"
1954 " /* clock value offset from Epoch is: offset * (1/freq) */\n"
1957 (unsigned long long) trace_clock_freq(),
1958 (unsigned long long) measure_clock_offset()
1963 ret
= lttng_metadata_printf(session
,
1964 "typealias integer {\n"
1965 " size = 27; align = 1; signed = false;\n"
1966 " map = clock.monotonic.value;\n"
1967 "} := uint27_clock_monotonic_t;\n"
1969 "typealias integer {\n"
1970 " size = 32; align = %u; signed = false;\n"
1971 " map = clock.monotonic.value;\n"
1972 "} := uint32_clock_monotonic_t;\n"
1974 "typealias integer {\n"
1975 " size = 64; align = %u; signed = false;\n"
1976 " map = clock.monotonic.value;\n"
1977 "} := uint64_clock_monotonic_t;\n\n",
1978 lttng_alignof(uint32_t) * CHAR_BIT
,
1979 lttng_alignof(uint64_t) * CHAR_BIT
1984 ret
= _lttng_stream_packet_context_declare(session
);
1988 ret
= _lttng_event_header_declare(session
);
1993 list_for_each_entry(chan
, &session
->chan
, list
) {
1994 ret
= _lttng_channel_metadata_statedump(session
, chan
);
1999 list_for_each_entry(event
, &session
->events
, list
) {
2000 ret
= _lttng_event_metadata_statedump(session
, event
->chan
, event
);
2004 session
->metadata_dumped
= 1;
2010 * lttng_transport_register - LTT transport registration
2011 * @transport: transport structure
2013 * Registers a transport which can be used as output to extract the data out of
2014 * LTTng. The module calling this registration function must ensure that no
2015 * trap-inducing code will be executed by the transport functions. E.g.
2016 * vmalloc_sync_all() must be called between a vmalloc and the moment the memory
2017 * is made visible to the transport function. This registration acts as a
2018 * vmalloc_sync_all. Therefore, only if the module allocates virtual memory
2019 * after its registration must it synchronize the TLBs.
2021 void lttng_transport_register(struct lttng_transport
*transport
)
2024 * Make sure no page fault can be triggered by the module about to be
2025 * registered. We deal with this here so we don't have to call
2026 * vmalloc_sync_all() in each module's init.
2028 wrapper_vmalloc_sync_all();
2030 mutex_lock(&sessions_mutex
);
2031 list_add_tail(&transport
->node
, <tng_transport_list
);
2032 mutex_unlock(&sessions_mutex
);
2034 EXPORT_SYMBOL_GPL(lttng_transport_register
);
2037 * lttng_transport_unregister - LTT transport unregistration
2038 * @transport: transport structure
2040 void lttng_transport_unregister(struct lttng_transport
*transport
)
2042 mutex_lock(&sessions_mutex
);
2043 list_del(&transport
->node
);
2044 mutex_unlock(&sessions_mutex
);
2046 EXPORT_SYMBOL_GPL(lttng_transport_unregister
);
2048 static int __init
lttng_events_init(void)
2052 ret
= wrapper_lttng_fixup_sig(THIS_MODULE
);
2056 ret
= lttng_tracepoint_init();
2059 event_cache
= KMEM_CACHE(lttng_event
, 0);
2064 ret
= lttng_abi_init();
2067 ret
= lttng_logger_init();
2075 kmem_cache_destroy(event_cache
);
2077 lttng_tracepoint_exit();
2081 module_init(lttng_events_init
);
2083 static void __exit
lttng_events_exit(void)
2085 struct lttng_session
*session
, *tmpsession
;
2087 lttng_logger_exit();
2089 list_for_each_entry_safe(session
, tmpsession
, &sessions
, list
)
2090 lttng_session_destroy(session
);
2091 kmem_cache_destroy(event_cache
);
2092 lttng_tracepoint_exit();
2095 module_exit(lttng_events_exit
);
2097 MODULE_LICENSE("GPL and additional rights");
2098 MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
2099 MODULE_DESCRIPTION("LTTng Events");
2100 MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION
) "."
2101 __stringify(LTTNG_MODULES_MINOR_VERSION
) "."
2102 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION
)
2103 LTTNG_MODULES_EXTRAVERSION
);