1 /* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
5 * Holds LTTng per-session event registry.
7 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
11 * This page_alloc.h wrapper needs to be included before gfpflags.h because it
12 * overrides a function with a define.
14 #include "wrapper/page_alloc.h"
16 #include <linux/module.h>
17 #include <linux/mutex.h>
18 #include <linux/sched.h>
19 #include <linux/slab.h>
20 #include <linux/jiffies.h>
21 #include <linux/utsname.h>
22 #include <linux/err.h>
23 #include <linux/seq_file.h>
24 #include <linux/file.h>
25 #include <linux/anon_inodes.h>
26 #include <wrapper/file.h>
27 #include <linux/jhash.h>
28 #include <linux/uaccess.h>
29 #include <linux/vmalloc.h>
30 #include <linux/dmi.h>
32 #include <wrapper/uuid.h>
33 #include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_mappings() */
34 #include <wrapper/random.h>
35 #include <wrapper/tracepoint.h>
36 #include <wrapper/list.h>
37 #include <wrapper/types.h>
38 #include <lttng-kernel-version.h>
39 #include <lttng-events.h>
40 #include <lttng-tracer.h>
41 #include <lttng-abi-old.h>
42 #include <lttng-endian.h>
43 #include <lttng-string-utils.h>
44 #include <wrapper/ringbuffer/backend.h>
45 #include <wrapper/ringbuffer/frontend.h>
46 #include <wrapper/time.h>
48 #define METADATA_CACHE_DEFAULT_SIZE 4096
50 static LIST_HEAD(sessions
);
51 static LIST_HEAD(lttng_transport_list
);
53 * Protect the sessions and metadata caches.
55 static DEFINE_MUTEX(sessions_mutex
);
56 static struct kmem_cache
*event_cache
;
58 static void lttng_session_lazy_sync_enablers(struct lttng_session
*session
);
59 static void lttng_session_sync_enablers(struct lttng_session
*session
);
60 static void lttng_enabler_destroy(struct lttng_enabler
*enabler
);
62 static void _lttng_event_destroy(struct lttng_event
*event
);
63 static void _lttng_channel_destroy(struct lttng_channel
*chan
);
64 static int _lttng_event_unregister(struct lttng_event
*event
);
66 int _lttng_event_metadata_statedump(struct lttng_session
*session
,
67 struct lttng_channel
*chan
,
68 struct lttng_event
*event
);
70 int _lttng_session_metadata_statedump(struct lttng_session
*session
);
72 void _lttng_metadata_channel_hangup(struct lttng_metadata_stream
*stream
);
74 int _lttng_field_statedump(struct lttng_session
*session
,
75 const struct lttng_event_field
*field
,
78 void synchronize_trace(void)
80 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,1,0) || \
81 LTTNG_RHEL_KERNEL_RANGE(4,18,0,193,0,0, 4,19,0,0,0,0))
87 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0))
88 #ifdef CONFIG_PREEMPT_RT_FULL
91 #else /* (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0)) */
92 #ifdef CONFIG_PREEMPT_RT
95 #endif /* (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0)) */
98 void lttng_lock_sessions(void)
100 mutex_lock(&sessions_mutex
);
103 void lttng_unlock_sessions(void)
105 mutex_unlock(&sessions_mutex
);
109 * Called with sessions lock held.
111 int lttng_session_active(void)
113 struct lttng_session
*iter
;
115 list_for_each_entry(iter
, &sessions
, list
) {
122 struct lttng_session
*lttng_session_create(void)
124 struct lttng_session
*session
;
125 struct lttng_metadata_cache
*metadata_cache
;
128 mutex_lock(&sessions_mutex
);
129 session
= lttng_kvzalloc(sizeof(struct lttng_session
), GFP_KERNEL
);
132 INIT_LIST_HEAD(&session
->chan
);
133 INIT_LIST_HEAD(&session
->events
);
134 lttng_guid_gen(&session
->uuid
);
136 metadata_cache
= kzalloc(sizeof(struct lttng_metadata_cache
),
139 goto err_free_session
;
140 metadata_cache
->data
= vzalloc(METADATA_CACHE_DEFAULT_SIZE
);
141 if (!metadata_cache
->data
)
143 metadata_cache
->cache_alloc
= METADATA_CACHE_DEFAULT_SIZE
;
144 kref_init(&metadata_cache
->refcount
);
145 mutex_init(&metadata_cache
->lock
);
146 session
->metadata_cache
= metadata_cache
;
147 INIT_LIST_HEAD(&metadata_cache
->metadata_stream
);
148 memcpy(&metadata_cache
->uuid
, &session
->uuid
,
149 sizeof(metadata_cache
->uuid
));
150 INIT_LIST_HEAD(&session
->enablers_head
);
151 for (i
= 0; i
< LTTNG_EVENT_HT_SIZE
; i
++)
152 INIT_HLIST_HEAD(&session
->events_ht
.table
[i
]);
153 list_add(&session
->list
, &sessions
);
154 session
->pid_tracker
.session
= session
;
155 session
->pid_tracker
.tracker_type
= TRACKER_PID
;
156 session
->vpid_tracker
.session
= session
;
157 session
->vpid_tracker
.tracker_type
= TRACKER_VPID
;
158 session
->uid_tracker
.session
= session
;
159 session
->uid_tracker
.tracker_type
= TRACKER_UID
;
160 session
->vuid_tracker
.session
= session
;
161 session
->vuid_tracker
.tracker_type
= TRACKER_VUID
;
162 session
->gid_tracker
.session
= session
;
163 session
->gid_tracker
.tracker_type
= TRACKER_GID
;
164 session
->vgid_tracker
.session
= session
;
165 session
->vgid_tracker
.tracker_type
= TRACKER_VGID
;
166 mutex_unlock(&sessions_mutex
);
170 kfree(metadata_cache
);
172 lttng_kvfree(session
);
174 mutex_unlock(&sessions_mutex
);
178 void metadata_cache_destroy(struct kref
*kref
)
180 struct lttng_metadata_cache
*cache
=
181 container_of(kref
, struct lttng_metadata_cache
, refcount
);
186 void lttng_session_destroy(struct lttng_session
*session
)
188 struct lttng_channel
*chan
, *tmpchan
;
189 struct lttng_event
*event
, *tmpevent
;
190 struct lttng_metadata_stream
*metadata_stream
;
191 struct lttng_enabler
*enabler
, *tmpenabler
;
194 mutex_lock(&sessions_mutex
);
195 WRITE_ONCE(session
->active
, 0);
196 list_for_each_entry(chan
, &session
->chan
, list
) {
197 ret
= lttng_syscalls_unregister(chan
);
200 list_for_each_entry(event
, &session
->events
, list
) {
201 ret
= _lttng_event_unregister(event
);
204 synchronize_trace(); /* Wait for in-flight events to complete */
205 list_for_each_entry(chan
, &session
->chan
, list
) {
206 ret
= lttng_syscalls_destroy(chan
);
209 list_for_each_entry_safe(enabler
, tmpenabler
,
210 &session
->enablers_head
, node
)
211 lttng_enabler_destroy(enabler
);
212 list_for_each_entry_safe(event
, tmpevent
, &session
->events
, list
)
213 _lttng_event_destroy(event
);
214 list_for_each_entry_safe(chan
, tmpchan
, &session
->chan
, list
) {
215 BUG_ON(chan
->channel_type
== METADATA_CHANNEL
);
216 _lttng_channel_destroy(chan
);
218 mutex_lock(&session
->metadata_cache
->lock
);
219 list_for_each_entry(metadata_stream
, &session
->metadata_cache
->metadata_stream
, list
)
220 _lttng_metadata_channel_hangup(metadata_stream
);
221 mutex_unlock(&session
->metadata_cache
->lock
);
222 lttng_id_tracker_destroy(&session
->pid_tracker
, false);
223 lttng_id_tracker_destroy(&session
->vpid_tracker
, false);
224 lttng_id_tracker_destroy(&session
->uid_tracker
, false);
225 lttng_id_tracker_destroy(&session
->vuid_tracker
, false);
226 lttng_id_tracker_destroy(&session
->gid_tracker
, false);
227 lttng_id_tracker_destroy(&session
->vgid_tracker
, false);
228 kref_put(&session
->metadata_cache
->refcount
, metadata_cache_destroy
);
229 list_del(&session
->list
);
230 mutex_unlock(&sessions_mutex
);
231 lttng_kvfree(session
);
234 int lttng_session_statedump(struct lttng_session
*session
)
238 mutex_lock(&sessions_mutex
);
239 ret
= lttng_statedump_start(session
);
240 mutex_unlock(&sessions_mutex
);
244 int lttng_session_enable(struct lttng_session
*session
)
247 struct lttng_channel
*chan
;
249 mutex_lock(&sessions_mutex
);
250 if (session
->active
) {
255 /* Set transient enabler state to "enabled" */
258 /* We need to sync enablers with session before activation. */
259 lttng_session_sync_enablers(session
);
262 * Snapshot the number of events per channel to know the type of header
265 list_for_each_entry(chan
, &session
->chan
, list
) {
266 if (chan
->header_type
)
267 continue; /* don't change it if session stop/restart */
268 if (chan
->free_event_id
< 31)
269 chan
->header_type
= 1; /* compact */
271 chan
->header_type
= 2; /* large */
274 /* Clear each stream's quiescent state. */
275 list_for_each_entry(chan
, &session
->chan
, list
) {
276 if (chan
->channel_type
!= METADATA_CHANNEL
)
277 lib_ring_buffer_clear_quiescent_channel(chan
->chan
);
280 WRITE_ONCE(session
->active
, 1);
281 WRITE_ONCE(session
->been_active
, 1);
282 ret
= _lttng_session_metadata_statedump(session
);
284 WRITE_ONCE(session
->active
, 0);
287 ret
= lttng_statedump_start(session
);
289 WRITE_ONCE(session
->active
, 0);
291 mutex_unlock(&sessions_mutex
);
295 int lttng_session_disable(struct lttng_session
*session
)
298 struct lttng_channel
*chan
;
300 mutex_lock(&sessions_mutex
);
301 if (!session
->active
) {
305 WRITE_ONCE(session
->active
, 0);
307 /* Set transient enabler state to "disabled" */
309 lttng_session_sync_enablers(session
);
311 /* Set each stream's quiescent state. */
312 list_for_each_entry(chan
, &session
->chan
, list
) {
313 if (chan
->channel_type
!= METADATA_CHANNEL
)
314 lib_ring_buffer_set_quiescent_channel(chan
->chan
);
317 mutex_unlock(&sessions_mutex
);
321 int lttng_session_metadata_regenerate(struct lttng_session
*session
)
324 struct lttng_channel
*chan
;
325 struct lttng_event
*event
;
326 struct lttng_metadata_cache
*cache
= session
->metadata_cache
;
327 struct lttng_metadata_stream
*stream
;
329 mutex_lock(&sessions_mutex
);
330 if (!session
->active
) {
335 mutex_lock(&cache
->lock
);
336 memset(cache
->data
, 0, cache
->cache_alloc
);
337 cache
->metadata_written
= 0;
339 list_for_each_entry(stream
, &session
->metadata_cache
->metadata_stream
, list
) {
340 stream
->metadata_out
= 0;
341 stream
->metadata_in
= 0;
343 mutex_unlock(&cache
->lock
);
345 session
->metadata_dumped
= 0;
346 list_for_each_entry(chan
, &session
->chan
, list
) {
347 chan
->metadata_dumped
= 0;
350 list_for_each_entry(event
, &session
->events
, list
) {
351 event
->metadata_dumped
= 0;
354 ret
= _lttng_session_metadata_statedump(session
);
357 mutex_unlock(&sessions_mutex
);
361 int lttng_channel_enable(struct lttng_channel
*channel
)
365 mutex_lock(&sessions_mutex
);
366 if (channel
->channel_type
== METADATA_CHANNEL
) {
370 if (channel
->enabled
) {
374 /* Set transient enabler state to "enabled" */
376 lttng_session_sync_enablers(channel
->session
);
377 /* Set atomically the state to "enabled" */
378 WRITE_ONCE(channel
->enabled
, 1);
380 mutex_unlock(&sessions_mutex
);
384 int lttng_channel_disable(struct lttng_channel
*channel
)
388 mutex_lock(&sessions_mutex
);
389 if (channel
->channel_type
== METADATA_CHANNEL
) {
393 if (!channel
->enabled
) {
397 /* Set atomically the state to "disabled" */
398 WRITE_ONCE(channel
->enabled
, 0);
399 /* Set transient enabler state to "enabled" */
401 lttng_session_sync_enablers(channel
->session
);
403 mutex_unlock(&sessions_mutex
);
407 int lttng_event_enable(struct lttng_event
*event
)
411 mutex_lock(&sessions_mutex
);
412 if (event
->chan
->channel_type
== METADATA_CHANNEL
) {
416 if (event
->enabled
) {
420 switch (event
->instrumentation
) {
421 case LTTNG_KERNEL_TRACEPOINT
:
422 case LTTNG_KERNEL_SYSCALL
:
425 case LTTNG_KERNEL_KPROBE
:
426 case LTTNG_KERNEL_UPROBE
:
427 case LTTNG_KERNEL_NOOP
:
428 WRITE_ONCE(event
->enabled
, 1);
430 case LTTNG_KERNEL_KRETPROBE
:
431 ret
= lttng_kretprobes_event_enable_state(event
, 1);
433 case LTTNG_KERNEL_FUNCTION
: /* Fall-through. */
439 mutex_unlock(&sessions_mutex
);
443 int lttng_event_disable(struct lttng_event
*event
)
447 mutex_lock(&sessions_mutex
);
448 if (event
->chan
->channel_type
== METADATA_CHANNEL
) {
452 if (!event
->enabled
) {
456 switch (event
->instrumentation
) {
457 case LTTNG_KERNEL_TRACEPOINT
:
458 case LTTNG_KERNEL_SYSCALL
:
461 case LTTNG_KERNEL_KPROBE
:
462 case LTTNG_KERNEL_UPROBE
:
463 case LTTNG_KERNEL_NOOP
:
464 WRITE_ONCE(event
->enabled
, 0);
466 case LTTNG_KERNEL_KRETPROBE
:
467 ret
= lttng_kretprobes_event_enable_state(event
, 0);
469 case LTTNG_KERNEL_FUNCTION
: /* Fall-through. */
475 mutex_unlock(&sessions_mutex
);
479 static struct lttng_transport
*lttng_transport_find(const char *name
)
481 struct lttng_transport
*transport
;
483 list_for_each_entry(transport
, <tng_transport_list
, node
) {
484 if (!strcmp(transport
->name
, name
))
490 struct lttng_channel
*lttng_channel_create(struct lttng_session
*session
,
491 const char *transport_name
,
493 size_t subbuf_size
, size_t num_subbuf
,
494 unsigned int switch_timer_interval
,
495 unsigned int read_timer_interval
,
496 enum channel_type channel_type
)
498 struct lttng_channel
*chan
;
499 struct lttng_transport
*transport
= NULL
;
501 mutex_lock(&sessions_mutex
);
502 if (session
->been_active
&& channel_type
!= METADATA_CHANNEL
)
503 goto active
; /* Refuse to add channel to active session */
504 transport
= lttng_transport_find(transport_name
);
506 printk(KERN_WARNING
"LTTng transport %s not found\n",
510 if (!try_module_get(transport
->owner
)) {
511 printk(KERN_WARNING
"LTT : Can't lock transport module.\n");
514 chan
= kzalloc(sizeof(struct lttng_channel
), GFP_KERNEL
);
517 chan
->session
= session
;
518 chan
->id
= session
->free_chan_id
++;
519 chan
->ops
= &transport
->ops
;
521 * Note: the channel creation op already writes into the packet
522 * headers. Therefore the "chan" information used as input
523 * should be already accessible.
525 chan
->chan
= transport
->ops
.channel_create(transport_name
,
526 chan
, buf_addr
, subbuf_size
, num_subbuf
,
527 switch_timer_interval
, read_timer_interval
);
532 chan
->transport
= transport
;
533 chan
->channel_type
= channel_type
;
534 list_add(&chan
->list
, &session
->chan
);
535 mutex_unlock(&sessions_mutex
);
542 module_put(transport
->owner
);
545 mutex_unlock(&sessions_mutex
);
550 * Only used internally at session destruction for per-cpu channels, and
551 * when metadata channel is released.
552 * Needs to be called with sessions mutex held.
555 void _lttng_channel_destroy(struct lttng_channel
*chan
)
557 chan
->ops
->channel_destroy(chan
->chan
);
558 module_put(chan
->transport
->owner
);
559 list_del(&chan
->list
);
560 lttng_destroy_context(chan
->ctx
);
564 void lttng_metadata_channel_destroy(struct lttng_channel
*chan
)
566 BUG_ON(chan
->channel_type
!= METADATA_CHANNEL
);
568 /* Protect the metadata cache with the sessions_mutex. */
569 mutex_lock(&sessions_mutex
);
570 _lttng_channel_destroy(chan
);
571 mutex_unlock(&sessions_mutex
);
573 EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy
);
576 void _lttng_metadata_channel_hangup(struct lttng_metadata_stream
*stream
)
578 stream
->finalized
= 1;
579 wake_up_interruptible(&stream
->read_wait
);
583 * Supports event creation while tracing session is active.
584 * Needs to be called with sessions mutex held.
586 struct lttng_event
*_lttng_event_create(struct lttng_channel
*chan
,
587 struct lttng_kernel_event
*event_param
,
589 const struct lttng_event_desc
*event_desc
,
590 enum lttng_kernel_instrumentation itype
)
592 struct lttng_session
*session
= chan
->session
;
593 struct lttng_event
*event
;
594 const char *event_name
;
595 struct hlist_head
*head
;
600 if (chan
->free_event_id
== -1U) {
606 case LTTNG_KERNEL_TRACEPOINT
:
607 event_name
= event_desc
->name
;
609 case LTTNG_KERNEL_KPROBE
:
610 case LTTNG_KERNEL_UPROBE
:
611 case LTTNG_KERNEL_KRETPROBE
:
612 case LTTNG_KERNEL_NOOP
:
613 case LTTNG_KERNEL_SYSCALL
:
614 event_name
= event_param
->name
;
616 case LTTNG_KERNEL_FUNCTION
: /* Fall-through. */
622 name_len
= strlen(event_name
);
623 hash
= jhash(event_name
, name_len
, 0);
624 head
= &session
->events_ht
.table
[hash
& (LTTNG_EVENT_HT_SIZE
- 1)];
625 lttng_hlist_for_each_entry(event
, head
, hlist
) {
626 WARN_ON_ONCE(!event
->desc
);
627 if (!strncmp(event
->desc
->name
, event_name
,
628 LTTNG_KERNEL_SYM_NAME_LEN
- 1)
629 && chan
== event
->chan
) {
635 event
= kmem_cache_zalloc(event_cache
, GFP_KERNEL
);
641 event
->filter
= filter
;
642 event
->id
= chan
->free_event_id
++;
643 event
->instrumentation
= itype
;
644 event
->evtype
= LTTNG_TYPE_EVENT
;
645 INIT_LIST_HEAD(&event
->bytecode_runtime_head
);
646 INIT_LIST_HEAD(&event
->enablers_ref_head
);
649 case LTTNG_KERNEL_TRACEPOINT
:
650 /* Event will be enabled by enabler sync. */
652 event
->registered
= 0;
653 event
->desc
= lttng_event_get(event_name
);
658 /* Populate lttng_event structure before event registration. */
661 case LTTNG_KERNEL_KPROBE
:
663 * Needs to be explicitly enabled after creation, since
664 * we may want to apply filters.
667 event
->registered
= 1;
669 * Populate lttng_event structure before event
673 ret
= lttng_kprobes_register(event_name
,
674 event_param
->u
.kprobe
.symbol_name
,
675 event_param
->u
.kprobe
.offset
,
676 event_param
->u
.kprobe
.addr
,
682 ret
= try_module_get(event
->desc
->owner
);
685 case LTTNG_KERNEL_KRETPROBE
:
687 struct lttng_event
*event_return
;
689 /* kretprobe defines 2 events */
691 * Needs to be explicitly enabled after creation, since
692 * we may want to apply filters.
695 event
->registered
= 1;
697 kmem_cache_zalloc(event_cache
, GFP_KERNEL
);
702 event_return
->chan
= chan
;
703 event_return
->filter
= filter
;
704 event_return
->id
= chan
->free_event_id
++;
705 event_return
->enabled
= 0;
706 event_return
->registered
= 1;
707 event_return
->instrumentation
= itype
;
708 INIT_LIST_HEAD(&event_return
->bytecode_runtime_head
);
709 INIT_LIST_HEAD(&event_return
->enablers_ref_head
);
711 * Populate lttng_event structure before kretprobe registration.
714 ret
= lttng_kretprobes_register(event_name
,
715 event_param
->u
.kretprobe
.symbol_name
,
716 event_param
->u
.kretprobe
.offset
,
717 event_param
->u
.kretprobe
.addr
,
718 event
, event_return
);
720 kmem_cache_free(event_cache
, event_return
);
724 /* Take 2 refs on the module: one per event. */
725 ret
= try_module_get(event
->desc
->owner
);
727 ret
= try_module_get(event
->desc
->owner
);
729 ret
= _lttng_event_metadata_statedump(chan
->session
, chan
,
731 WARN_ON_ONCE(ret
> 0);
733 kmem_cache_free(event_cache
, event_return
);
734 module_put(event
->desc
->owner
);
735 module_put(event
->desc
->owner
);
736 goto statedump_error
;
738 list_add(&event_return
->list
, &chan
->session
->events
);
741 case LTTNG_KERNEL_NOOP
:
742 case LTTNG_KERNEL_SYSCALL
:
744 * Needs to be explicitly enabled after creation, since
745 * we may want to apply filters.
748 event
->registered
= 0;
749 event
->desc
= event_desc
;
750 switch (event_param
->u
.syscall
.entryexit
) {
751 case LTTNG_KERNEL_SYSCALL_ENTRYEXIT
:
754 case LTTNG_KERNEL_SYSCALL_ENTRY
:
755 event
->u
.syscall
.entryexit
= LTTNG_SYSCALL_ENTRY
;
757 case LTTNG_KERNEL_SYSCALL_EXIT
:
758 event
->u
.syscall
.entryexit
= LTTNG_SYSCALL_EXIT
;
761 switch (event_param
->u
.syscall
.abi
) {
762 case LTTNG_KERNEL_SYSCALL_ABI_ALL
:
765 case LTTNG_KERNEL_SYSCALL_ABI_NATIVE
:
766 event
->u
.syscall
.abi
= LTTNG_SYSCALL_ABI_NATIVE
;
768 case LTTNG_KERNEL_SYSCALL_ABI_COMPAT
:
769 event
->u
.syscall
.abi
= LTTNG_SYSCALL_ABI_COMPAT
;
777 case LTTNG_KERNEL_UPROBE
:
779 * Needs to be explicitly enabled after creation, since
780 * we may want to apply filters.
783 event
->registered
= 1;
786 * Populate lttng_event structure before event
791 ret
= lttng_uprobes_register(event_param
->name
,
792 event_param
->u
.uprobe
.fd
,
796 ret
= try_module_get(event
->desc
->owner
);
799 case LTTNG_KERNEL_FUNCTION
: /* Fall-through */
805 ret
= _lttng_event_metadata_statedump(chan
->session
, chan
, event
);
806 WARN_ON_ONCE(ret
> 0);
808 goto statedump_error
;
810 hlist_add_head(&event
->hlist
, head
);
811 list_add(&event
->list
, &chan
->session
->events
);
815 /* If a statedump error occurs, events will not be readable. */
817 kmem_cache_free(event_cache
, event
);
825 struct lttng_event
*lttng_event_create(struct lttng_channel
*chan
,
826 struct lttng_kernel_event
*event_param
,
828 const struct lttng_event_desc
*event_desc
,
829 enum lttng_kernel_instrumentation itype
)
831 struct lttng_event
*event
;
833 mutex_lock(&sessions_mutex
);
834 event
= _lttng_event_create(chan
, event_param
, filter
, event_desc
,
836 mutex_unlock(&sessions_mutex
);
840 /* Only used for tracepoints for now. */
842 void register_event(struct lttng_event
*event
)
844 const struct lttng_event_desc
*desc
;
847 if (event
->registered
)
851 switch (event
->instrumentation
) {
852 case LTTNG_KERNEL_TRACEPOINT
:
853 ret
= lttng_wrapper_tracepoint_probe_register(desc
->kname
,
854 desc
->probe_callback
,
857 case LTTNG_KERNEL_SYSCALL
:
858 ret
= lttng_syscall_filter_enable(event
->chan
, event
);
860 case LTTNG_KERNEL_KPROBE
:
861 case LTTNG_KERNEL_UPROBE
:
862 case LTTNG_KERNEL_KRETPROBE
:
863 case LTTNG_KERNEL_NOOP
:
866 case LTTNG_KERNEL_FUNCTION
: /* Fall-through */
871 event
->registered
= 1;
875 * Only used internally at session destruction.
877 int _lttng_event_unregister(struct lttng_event
*event
)
879 const struct lttng_event_desc
*desc
;
882 if (!event
->registered
)
886 switch (event
->instrumentation
) {
887 case LTTNG_KERNEL_TRACEPOINT
:
888 ret
= lttng_wrapper_tracepoint_probe_unregister(event
->desc
->kname
,
889 event
->desc
->probe_callback
,
892 case LTTNG_KERNEL_KPROBE
:
893 lttng_kprobes_unregister(event
);
896 case LTTNG_KERNEL_KRETPROBE
:
897 lttng_kretprobes_unregister(event
);
900 case LTTNG_KERNEL_SYSCALL
:
901 ret
= lttng_syscall_filter_disable(event
->chan
, event
);
903 case LTTNG_KERNEL_NOOP
:
906 case LTTNG_KERNEL_UPROBE
:
907 lttng_uprobes_unregister(event
);
910 case LTTNG_KERNEL_FUNCTION
: /* Fall-through */
915 event
->registered
= 0;
920 * Only used internally at session destruction.
923 void _lttng_event_destroy(struct lttng_event
*event
)
925 struct lttng_enabler_ref
*enabler_ref
, *tmp_enabler_ref
;
927 switch (event
->instrumentation
) {
928 case LTTNG_KERNEL_TRACEPOINT
:
929 lttng_event_put(event
->desc
);
931 case LTTNG_KERNEL_KPROBE
:
932 module_put(event
->desc
->owner
);
933 lttng_kprobes_destroy_private(event
);
935 case LTTNG_KERNEL_KRETPROBE
:
936 module_put(event
->desc
->owner
);
937 lttng_kretprobes_destroy_private(event
);
939 case LTTNG_KERNEL_NOOP
:
940 case LTTNG_KERNEL_SYSCALL
:
942 case LTTNG_KERNEL_UPROBE
:
943 module_put(event
->desc
->owner
);
944 lttng_uprobes_destroy_private(event
);
946 case LTTNG_KERNEL_FUNCTION
: /* Fall-through */
950 list_del(&event
->list
);
951 lttng_destroy_context(event
->ctx
);
952 lttng_free_event_filter_runtime(event
);
953 /* Free event enabler refs */
954 list_for_each_entry_safe(enabler_ref
, tmp_enabler_ref
,
955 &event
->enablers_ref_head
, node
)
957 kmem_cache_free(event_cache
, event
);
960 struct lttng_id_tracker
*get_tracker(struct lttng_session
*session
,
961 enum tracker_type tracker_type
)
963 switch (tracker_type
) {
965 return &session
->pid_tracker
;
967 return &session
->vpid_tracker
;
969 return &session
->uid_tracker
;
971 return &session
->vuid_tracker
;
973 return &session
->gid_tracker
;
975 return &session
->vgid_tracker
;
982 int lttng_session_track_id(struct lttng_session
*session
,
983 enum tracker_type tracker_type
, int id
)
985 struct lttng_id_tracker
*tracker
;
988 tracker
= get_tracker(session
, tracker_type
);
993 mutex_lock(&sessions_mutex
);
995 /* track all ids: destroy tracker. */
996 lttng_id_tracker_destroy(tracker
, true);
999 ret
= lttng_id_tracker_add(tracker
, id
);
1001 mutex_unlock(&sessions_mutex
);
1005 int lttng_session_untrack_id(struct lttng_session
*session
,
1006 enum tracker_type tracker_type
, int id
)
1008 struct lttng_id_tracker
*tracker
;
1011 tracker
= get_tracker(session
, tracker_type
);
1016 mutex_lock(&sessions_mutex
);
1018 /* untrack all ids: replace by empty tracker. */
1019 ret
= lttng_id_tracker_empty_set(tracker
);
1021 ret
= lttng_id_tracker_del(tracker
, id
);
1023 mutex_unlock(&sessions_mutex
);
1028 void *id_list_start(struct seq_file
*m
, loff_t
*pos
)
1030 struct lttng_id_tracker
*id_tracker
= m
->private;
1031 struct lttng_id_tracker_rcu
*id_tracker_p
= id_tracker
->p
;
1032 struct lttng_id_hash_node
*e
;
1035 mutex_lock(&sessions_mutex
);
1037 for (i
= 0; i
< LTTNG_ID_TABLE_SIZE
; i
++) {
1038 struct hlist_head
*head
= &id_tracker_p
->id_hash
[i
];
1040 lttng_hlist_for_each_entry(e
, head
, hlist
) {
1046 /* ID tracker disabled. */
1047 if (iter
>= *pos
&& iter
== 0) {
1048 return id_tracker_p
; /* empty tracker */
1056 /* Called with sessions_mutex held. */
1058 void *id_list_next(struct seq_file
*m
, void *p
, loff_t
*ppos
)
1060 struct lttng_id_tracker
*id_tracker
= m
->private;
1061 struct lttng_id_tracker_rcu
*id_tracker_p
= id_tracker
->p
;
1062 struct lttng_id_hash_node
*e
;
1067 for (i
= 0; i
< LTTNG_ID_TABLE_SIZE
; i
++) {
1068 struct hlist_head
*head
= &id_tracker_p
->id_hash
[i
];
1070 lttng_hlist_for_each_entry(e
, head
, hlist
) {
1071 if (iter
++ >= *ppos
)
1076 /* ID tracker disabled. */
1077 if (iter
>= *ppos
&& iter
== 0)
1078 return p
; /* empty tracker */
1087 void id_list_stop(struct seq_file
*m
, void *p
)
1089 mutex_unlock(&sessions_mutex
);
1093 int id_list_show(struct seq_file
*m
, void *p
)
1095 struct lttng_id_tracker
*id_tracker
= m
->private;
1096 struct lttng_id_tracker_rcu
*id_tracker_p
= id_tracker
->p
;
1099 if (p
== id_tracker_p
) {
1100 /* Tracker disabled. */
1103 const struct lttng_id_hash_node
*e
= p
;
1105 id
= lttng_id_tracker_get_node_id(e
);
1107 switch (id_tracker
->tracker_type
) {
1109 seq_printf(m
, "process { pid = %d; };\n", id
);
1112 seq_printf(m
, "process { vpid = %d; };\n", id
);
1115 seq_printf(m
, "user { uid = %d; };\n", id
);
1118 seq_printf(m
, "user { vuid = %d; };\n", id
);
1121 seq_printf(m
, "group { gid = %d; };\n", id
);
1124 seq_printf(m
, "group { vgid = %d; };\n", id
);
1127 seq_printf(m
, "UNKNOWN { field = %d };\n", id
);
1133 const struct seq_operations lttng_tracker_ids_list_seq_ops
= {
1134 .start
= id_list_start
,
1135 .next
= id_list_next
,
1136 .stop
= id_list_stop
,
1137 .show
= id_list_show
,
1141 int lttng_tracker_ids_list_open(struct inode
*inode
, struct file
*file
)
1143 return seq_open(file
, <tng_tracker_ids_list_seq_ops
);
1147 int lttng_tracker_ids_list_release(struct inode
*inode
, struct file
*file
)
1149 struct seq_file
*m
= file
->private_data
;
1150 struct lttng_id_tracker
*id_tracker
= m
->private;
1153 WARN_ON_ONCE(!id_tracker
);
1154 ret
= seq_release(inode
, file
);
1156 fput(id_tracker
->session
->file
);
1160 const struct file_operations lttng_tracker_ids_list_fops
= {
1161 .owner
= THIS_MODULE
,
1162 .open
= lttng_tracker_ids_list_open
,
1164 .llseek
= seq_lseek
,
1165 .release
= lttng_tracker_ids_list_release
,
1168 int lttng_session_list_tracker_ids(struct lttng_session
*session
,
1169 enum tracker_type tracker_type
)
1171 struct file
*tracker_ids_list_file
;
1175 file_fd
= lttng_get_unused_fd();
1181 tracker_ids_list_file
= anon_inode_getfile("[lttng_tracker_ids_list]",
1182 <tng_tracker_ids_list_fops
,
1184 if (IS_ERR(tracker_ids_list_file
)) {
1185 ret
= PTR_ERR(tracker_ids_list_file
);
1188 if (!atomic_long_add_unless(&session
->file
->f_count
, 1, LONG_MAX
)) {
1190 goto refcount_error
;
1192 ret
= lttng_tracker_ids_list_fops
.open(NULL
, tracker_ids_list_file
);
1195 m
= tracker_ids_list_file
->private_data
;
1197 m
->private = get_tracker(session
, tracker_type
);
1198 BUG_ON(!m
->private);
1199 fd_install(file_fd
, tracker_ids_list_file
);
1204 atomic_long_dec(&session
->file
->f_count
);
1206 fput(tracker_ids_list_file
);
1208 put_unused_fd(file_fd
);
1214 * Enabler management.
1217 int lttng_match_enabler_star_glob(const char *desc_name
,
1218 const char *pattern
)
1220 if (!strutils_star_glob_match(pattern
, LTTNG_SIZE_MAX
,
1221 desc_name
, LTTNG_SIZE_MAX
))
1227 int lttng_match_enabler_name(const char *desc_name
,
1230 if (strcmp(desc_name
, name
))
1236 int lttng_desc_match_enabler(const struct lttng_event_desc
*desc
,
1237 struct lttng_enabler
*enabler
)
1239 const char *desc_name
, *enabler_name
;
1240 bool compat
= false, entry
= false;
1242 enabler_name
= enabler
->event_param
.name
;
1243 switch (enabler
->event_param
.instrumentation
) {
1244 case LTTNG_KERNEL_TRACEPOINT
:
1245 desc_name
= desc
->name
;
1246 switch (enabler
->type
) {
1247 case LTTNG_ENABLER_STAR_GLOB
:
1248 return lttng_match_enabler_star_glob(desc_name
, enabler_name
);
1249 case LTTNG_ENABLER_NAME
:
1250 return lttng_match_enabler_name(desc_name
, enabler_name
);
1255 case LTTNG_KERNEL_SYSCALL
:
1256 desc_name
= desc
->name
;
1257 if (!strncmp(desc_name
, "compat_", strlen("compat_"))) {
1258 desc_name
+= strlen("compat_");
1261 if (!strncmp(desc_name
, "syscall_exit_",
1262 strlen("syscall_exit_"))) {
1263 desc_name
+= strlen("syscall_exit_");
1264 } else if (!strncmp(desc_name
, "syscall_entry_",
1265 strlen("syscall_entry_"))) {
1266 desc_name
+= strlen("syscall_entry_");
1272 switch (enabler
->event_param
.u
.syscall
.entryexit
) {
1273 case LTTNG_KERNEL_SYSCALL_ENTRYEXIT
:
1275 case LTTNG_KERNEL_SYSCALL_ENTRY
:
1279 case LTTNG_KERNEL_SYSCALL_EXIT
:
1286 switch (enabler
->event_param
.u
.syscall
.abi
) {
1287 case LTTNG_KERNEL_SYSCALL_ABI_ALL
:
1289 case LTTNG_KERNEL_SYSCALL_ABI_NATIVE
:
1293 case LTTNG_KERNEL_SYSCALL_ABI_COMPAT
:
1300 switch (enabler
->event_param
.u
.syscall
.match
) {
1301 case LTTNG_SYSCALL_MATCH_NAME
:
1302 switch (enabler
->type
) {
1303 case LTTNG_ENABLER_STAR_GLOB
:
1304 return lttng_match_enabler_star_glob(desc_name
, enabler_name
);
1305 case LTTNG_ENABLER_NAME
:
1306 return lttng_match_enabler_name(desc_name
, enabler_name
);
1311 case LTTNG_SYSCALL_MATCH_NR
:
1312 return -EINVAL
; /* Not implemented. */
1324 int lttng_event_match_enabler(struct lttng_event
*event
,
1325 struct lttng_enabler
*enabler
)
1327 if (enabler
->event_param
.instrumentation
!= event
->instrumentation
)
1329 if (lttng_desc_match_enabler(event
->desc
, enabler
)
1330 && event
->chan
== enabler
->chan
)
1337 struct lttng_enabler_ref
*lttng_event_enabler_ref(struct lttng_event
*event
,
1338 struct lttng_enabler
*enabler
)
1340 struct lttng_enabler_ref
*enabler_ref
;
1342 list_for_each_entry(enabler_ref
,
1343 &event
->enablers_ref_head
, node
) {
1344 if (enabler_ref
->ref
== enabler
)
1351 void lttng_create_tracepoint_if_missing(struct lttng_enabler
*enabler
)
1353 struct lttng_session
*session
= enabler
->chan
->session
;
1354 struct lttng_probe_desc
*probe_desc
;
1355 const struct lttng_event_desc
*desc
;
1357 struct list_head
*probe_list
;
1359 probe_list
= lttng_get_probe_list_head();
1361 * For each probe event, if we find that a probe event matches
1362 * our enabler, create an associated lttng_event if not
1365 list_for_each_entry(probe_desc
, probe_list
, head
) {
1366 for (i
= 0; i
< probe_desc
->nr_events
; i
++) {
1368 struct hlist_head
*head
;
1369 const char *event_name
;
1372 struct lttng_event
*event
;
1374 desc
= probe_desc
->event_desc
[i
];
1375 if (!lttng_desc_match_enabler(desc
, enabler
))
1377 event_name
= desc
->name
;
1378 name_len
= strlen(event_name
);
1381 * Check if already created.
1383 hash
= jhash(event_name
, name_len
, 0);
1384 head
= &session
->events_ht
.table
[hash
& (LTTNG_EVENT_HT_SIZE
- 1)];
1385 lttng_hlist_for_each_entry(event
, head
, hlist
) {
1386 if (event
->desc
== desc
1387 && event
->chan
== enabler
->chan
)
1394 * We need to create an event for this
1397 event
= _lttng_event_create(enabler
->chan
,
1399 LTTNG_KERNEL_TRACEPOINT
);
1401 printk(KERN_INFO
"Unable to create event %s\n",
1402 probe_desc
->event_desc
[i
]->name
);
1409 void lttng_create_syscall_if_missing(struct lttng_enabler
*enabler
)
1413 ret
= lttng_syscalls_register(enabler
->chan
, NULL
);
1418 * Create struct lttng_event if it is missing and present in the list of
1419 * tracepoint probes.
1420 * Should be called with sessions mutex held.
1423 void lttng_create_event_if_missing(struct lttng_enabler
*enabler
)
1425 switch (enabler
->event_param
.instrumentation
) {
1426 case LTTNG_KERNEL_TRACEPOINT
:
1427 lttng_create_tracepoint_if_missing(enabler
);
1429 case LTTNG_KERNEL_SYSCALL
:
1430 lttng_create_syscall_if_missing(enabler
);
1439 * Create events associated with an enabler (if not already present),
1440 * and add backward reference from the event to the enabler.
1441 * Should be called with sessions mutex held.
1444 int lttng_enabler_ref_events(struct lttng_enabler
*enabler
)
1446 struct lttng_channel
*chan
= enabler
->chan
;
1447 struct lttng_session
*session
= chan
->session
;
1448 struct lttng_event
*event
;
1450 if (enabler
->event_param
.instrumentation
== LTTNG_KERNEL_SYSCALL
&&
1451 enabler
->event_param
.u
.syscall
.entryexit
== LTTNG_KERNEL_SYSCALL_ENTRYEXIT
&&
1452 enabler
->event_param
.u
.syscall
.abi
== LTTNG_KERNEL_SYSCALL_ABI_ALL
&&
1453 enabler
->event_param
.u
.syscall
.match
== LTTNG_SYSCALL_MATCH_NAME
&&
1454 !strcmp(enabler
->event_param
.name
, "*")) {
1455 if (enabler
->enabled
)
1456 WRITE_ONCE(chan
->syscall_all
, 1);
1458 WRITE_ONCE(chan
->syscall_all
, 0);
1461 /* First ensure that probe events are created for this enabler. */
1462 lttng_create_event_if_missing(enabler
);
1464 /* For each event matching enabler in session event list. */
1465 list_for_each_entry(event
, &session
->events
, list
) {
1466 struct lttng_enabler_ref
*enabler_ref
;
1468 if (!lttng_event_match_enabler(event
, enabler
))
1470 enabler_ref
= lttng_event_enabler_ref(event
, enabler
);
1473 * If no backward ref, create it.
1474 * Add backward ref from event to enabler.
1476 enabler_ref
= kzalloc(sizeof(*enabler_ref
), GFP_KERNEL
);
1479 enabler_ref
->ref
= enabler
;
1480 list_add(&enabler_ref
->node
,
1481 &event
->enablers_ref_head
);
1485 * Link filter bytecodes if not linked yet.
1487 lttng_enabler_event_link_bytecode(event
, enabler
);
1489 /* TODO: merge event context. */
1495 * Called at module load: connect the probe on all enablers matching
1497 * Called with sessions lock held.
1499 int lttng_fix_pending_events(void)
1501 struct lttng_session
*session
;
1503 list_for_each_entry(session
, &sessions
, list
)
1504 lttng_session_lazy_sync_enablers(session
);
1508 struct lttng_enabler
*lttng_enabler_create(enum lttng_enabler_type type
,
1509 struct lttng_kernel_event
*event_param
,
1510 struct lttng_channel
*chan
)
1512 struct lttng_enabler
*enabler
;
1514 enabler
= kzalloc(sizeof(*enabler
), GFP_KERNEL
);
1517 enabler
->type
= type
;
1518 INIT_LIST_HEAD(&enabler
->filter_bytecode_head
);
1519 memcpy(&enabler
->event_param
, event_param
,
1520 sizeof(enabler
->event_param
));
1521 enabler
->chan
= chan
;
1523 enabler
->enabled
= 0;
1524 enabler
->evtype
= LTTNG_TYPE_ENABLER
;
1525 mutex_lock(&sessions_mutex
);
1526 list_add(&enabler
->node
, &enabler
->chan
->session
->enablers_head
);
1527 lttng_session_lazy_sync_enablers(enabler
->chan
->session
);
1528 mutex_unlock(&sessions_mutex
);
1532 int lttng_enabler_enable(struct lttng_enabler
*enabler
)
1534 mutex_lock(&sessions_mutex
);
1535 enabler
->enabled
= 1;
1536 lttng_session_lazy_sync_enablers(enabler
->chan
->session
);
1537 mutex_unlock(&sessions_mutex
);
1541 int lttng_enabler_disable(struct lttng_enabler
*enabler
)
1543 mutex_lock(&sessions_mutex
);
1544 enabler
->enabled
= 0;
1545 lttng_session_lazy_sync_enablers(enabler
->chan
->session
);
1546 mutex_unlock(&sessions_mutex
);
1550 int lttng_enabler_attach_bytecode(struct lttng_enabler
*enabler
,
1551 struct lttng_kernel_filter_bytecode __user
*bytecode
)
1553 struct lttng_filter_bytecode_node
*bytecode_node
;
1554 uint32_t bytecode_len
;
1557 ret
= get_user(bytecode_len
, &bytecode
->len
);
1560 bytecode_node
= kzalloc(sizeof(*bytecode_node
) + bytecode_len
,
1564 ret
= copy_from_user(&bytecode_node
->bc
, bytecode
,
1565 sizeof(*bytecode
) + bytecode_len
);
1568 bytecode_node
->enabler
= enabler
;
1569 /* Enforce length based on allocated size */
1570 bytecode_node
->bc
.len
= bytecode_len
;
1571 list_add_tail(&bytecode_node
->node
, &enabler
->filter_bytecode_head
);
1572 lttng_session_lazy_sync_enablers(enabler
->chan
->session
);
1576 kfree(bytecode_node
);
1580 int lttng_event_add_callsite(struct lttng_event
*event
,
1581 struct lttng_kernel_event_callsite __user
*callsite
)
1584 switch (event
->instrumentation
) {
1585 case LTTNG_KERNEL_UPROBE
:
1586 return lttng_uprobes_add_callsite(event
, callsite
);
1592 int lttng_enabler_attach_context(struct lttng_enabler
*enabler
,
1593 struct lttng_kernel_context
*context_param
)
1599 void lttng_enabler_destroy(struct lttng_enabler
*enabler
)
1601 struct lttng_filter_bytecode_node
*filter_node
, *tmp_filter_node
;
1603 /* Destroy filter bytecode */
1604 list_for_each_entry_safe(filter_node
, tmp_filter_node
,
1605 &enabler
->filter_bytecode_head
, node
) {
1609 /* Destroy contexts */
1610 lttng_destroy_context(enabler
->ctx
);
1612 list_del(&enabler
->node
);
1617 * lttng_session_sync_enablers should be called just before starting a
1619 * Should be called with sessions mutex held.
1622 void lttng_session_sync_enablers(struct lttng_session
*session
)
1624 struct lttng_enabler
*enabler
;
1625 struct lttng_event
*event
;
1627 list_for_each_entry(enabler
, &session
->enablers_head
, node
)
1628 lttng_enabler_ref_events(enabler
);
1630 * For each event, if at least one of its enablers is enabled,
1631 * and its channel and session transient states are enabled, we
1632 * enable the event, else we disable it.
1634 list_for_each_entry(event
, &session
->events
, list
) {
1635 struct lttng_enabler_ref
*enabler_ref
;
1636 struct lttng_bytecode_runtime
*runtime
;
1637 int enabled
= 0, has_enablers_without_bytecode
= 0;
1639 switch (event
->instrumentation
) {
1640 case LTTNG_KERNEL_TRACEPOINT
:
1641 case LTTNG_KERNEL_SYSCALL
:
1643 list_for_each_entry(enabler_ref
,
1644 &event
->enablers_ref_head
, node
) {
1645 if (enabler_ref
->ref
->enabled
) {
1652 /* Not handled with lazy sync. */
1656 * Enabled state is based on union of enablers, with
1657 * intesection of session and channel transient enable
1660 enabled
= enabled
&& session
->tstate
&& event
->chan
->tstate
;
1662 WRITE_ONCE(event
->enabled
, enabled
);
1664 * Sync tracepoint registration with event enabled
1668 register_event(event
);
1670 _lttng_event_unregister(event
);
1673 /* Check if has enablers without bytecode enabled */
1674 list_for_each_entry(enabler_ref
,
1675 &event
->enablers_ref_head
, node
) {
1676 if (enabler_ref
->ref
->enabled
1677 && list_empty(&enabler_ref
->ref
->filter_bytecode_head
)) {
1678 has_enablers_without_bytecode
= 1;
1682 event
->has_enablers_without_bytecode
=
1683 has_enablers_without_bytecode
;
1685 /* Enable filters */
1686 list_for_each_entry(runtime
,
1687 &event
->bytecode_runtime_head
, node
)
1688 lttng_filter_sync_state(runtime
);
1693 * Apply enablers to session events, adding events to session if need
1694 * be. It is required after each modification applied to an active
1695 * session, and right before session "start".
1696 * "lazy" sync means we only sync if required.
1697 * Should be called with sessions mutex held.
1700 void lttng_session_lazy_sync_enablers(struct lttng_session
*session
)
1702 /* We can skip if session is not active */
1703 if (!session
->active
)
1705 lttng_session_sync_enablers(session
);
1709 * Serialize at most one packet worth of metadata into a metadata
1711 * We grab the metadata cache mutex to get exclusive access to our metadata
1712 * buffer and to the metadata cache. Exclusive access to the metadata buffer
1713 * allows us to do racy operations such as looking for remaining space left in
1714 * packet and write, since mutual exclusion protects us from concurrent writes.
1715 * Mutual exclusion on the metadata cache allow us to read the cache content
1716 * without racing against reallocation of the cache by updates.
1717 * Returns the number of bytes written in the channel, 0 if no data
1718 * was written and a negative value on error.
1720 int lttng_metadata_output_channel(struct lttng_metadata_stream
*stream
,
1721 struct channel
*chan
, bool *coherent
)
1723 struct lib_ring_buffer_ctx ctx
;
1725 size_t len
, reserve_len
;
1728 * Ensure we support mutiple get_next / put sequences followed by
1729 * put_next. The metadata cache lock protects reading the metadata
1730 * cache. It can indeed be read concurrently by "get_next_subbuf" and
1731 * "flush" operations on the buffer invoked by different processes.
1732 * Moreover, since the metadata cache memory can be reallocated, we
1733 * need to have exclusive access against updates even though we only
1736 mutex_lock(&stream
->metadata_cache
->lock
);
1737 WARN_ON(stream
->metadata_in
< stream
->metadata_out
);
1738 if (stream
->metadata_in
!= stream
->metadata_out
)
1741 /* Metadata regenerated, change the version. */
1742 if (stream
->metadata_cache
->version
!= stream
->version
)
1743 stream
->version
= stream
->metadata_cache
->version
;
1745 len
= stream
->metadata_cache
->metadata_written
-
1746 stream
->metadata_in
;
1749 reserve_len
= min_t(size_t,
1750 stream
->transport
->ops
.packet_avail_size(chan
),
1752 lib_ring_buffer_ctx_init(&ctx
, chan
, NULL
, reserve_len
,
1755 * If reservation failed, return an error to the caller.
1757 ret
= stream
->transport
->ops
.event_reserve(&ctx
, 0);
1759 printk(KERN_WARNING
"LTTng: Metadata event reservation failed\n");
1760 stream
->coherent
= false;
1763 stream
->transport
->ops
.event_write(&ctx
,
1764 stream
->metadata_cache
->data
+ stream
->metadata_in
,
1766 stream
->transport
->ops
.event_commit(&ctx
);
1767 stream
->metadata_in
+= reserve_len
;
1768 if (reserve_len
< len
)
1769 stream
->coherent
= false;
1771 stream
->coherent
= true;
1776 *coherent
= stream
->coherent
;
1777 mutex_unlock(&stream
->metadata_cache
->lock
);
1782 void lttng_metadata_begin(struct lttng_session
*session
)
1784 if (atomic_inc_return(&session
->metadata_cache
->producing
) == 1)
1785 mutex_lock(&session
->metadata_cache
->lock
);
1789 void lttng_metadata_end(struct lttng_session
*session
)
1791 WARN_ON_ONCE(!atomic_read(&session
->metadata_cache
->producing
));
1792 if (atomic_dec_return(&session
->metadata_cache
->producing
) == 0) {
1793 struct lttng_metadata_stream
*stream
;
1795 list_for_each_entry(stream
, &session
->metadata_cache
->metadata_stream
, list
)
1796 wake_up_interruptible(&stream
->read_wait
);
1797 mutex_unlock(&session
->metadata_cache
->lock
);
1802 * Write the metadata to the metadata cache.
1803 * Must be called with sessions_mutex held.
1804 * The metadata cache lock protects us from concurrent read access from
1805 * thread outputting metadata content to ring buffer.
1806 * The content of the printf is printed as a single atomic metadata
1809 int lttng_metadata_printf(struct lttng_session
*session
,
1810 const char *fmt
, ...)
1816 WARN_ON_ONCE(!LTTNG_READ_ONCE(session
->active
));
1819 str
= kvasprintf(GFP_KERNEL
, fmt
, ap
);
1825 WARN_ON_ONCE(!atomic_read(&session
->metadata_cache
->producing
));
1826 if (session
->metadata_cache
->metadata_written
+ len
>
1827 session
->metadata_cache
->cache_alloc
) {
1828 char *tmp_cache_realloc
;
1829 unsigned int tmp_cache_alloc_size
;
1831 tmp_cache_alloc_size
= max_t(unsigned int,
1832 session
->metadata_cache
->cache_alloc
+ len
,
1833 session
->metadata_cache
->cache_alloc
<< 1);
1834 tmp_cache_realloc
= vzalloc(tmp_cache_alloc_size
);
1835 if (!tmp_cache_realloc
)
1837 if (session
->metadata_cache
->data
) {
1838 memcpy(tmp_cache_realloc
,
1839 session
->metadata_cache
->data
,
1840 session
->metadata_cache
->cache_alloc
);
1841 vfree(session
->metadata_cache
->data
);
1844 session
->metadata_cache
->cache_alloc
= tmp_cache_alloc_size
;
1845 session
->metadata_cache
->data
= tmp_cache_realloc
;
1847 memcpy(session
->metadata_cache
->data
+
1848 session
->metadata_cache
->metadata_written
,
1850 session
->metadata_cache
->metadata_written
+= len
;
1861 int print_tabs(struct lttng_session
*session
, size_t nesting
)
1865 for (i
= 0; i
< nesting
; i
++) {
1868 ret
= lttng_metadata_printf(session
, " ");
1877 * Must be called with sessions_mutex held.
1880 int _lttng_struct_type_statedump(struct lttng_session
*session
,
1881 const struct lttng_type
*type
,
1885 uint32_t i
, nr_fields
;
1887 ret
= print_tabs(session
, nesting
);
1890 ret
= lttng_metadata_printf(session
,
1894 nr_fields
= type
->u
._struct
.nr_fields
;
1895 for (i
= 0; i
< nr_fields
; i
++) {
1896 const struct lttng_event_field
*iter_field
;
1898 iter_field
= &type
->u
._struct
.fields
[i
];
1899 ret
= _lttng_field_statedump(session
, iter_field
, nesting
+ 1);
1903 ret
= print_tabs(session
, nesting
);
1906 ret
= lttng_metadata_printf(session
,
1912 * Must be called with sessions_mutex held.
1915 int _lttng_struct_statedump(struct lttng_session
*session
,
1916 const struct lttng_event_field
*field
,
1921 ret
= _lttng_struct_type_statedump(session
,
1922 &field
->type
, nesting
);
1925 ret
= lttng_metadata_printf(session
,
1932 * Must be called with sessions_mutex held.
1935 int _lttng_variant_type_statedump(struct lttng_session
*session
,
1936 const struct lttng_type
*type
,
1940 uint32_t i
, nr_choices
;
1942 ret
= print_tabs(session
, nesting
);
1945 ret
= lttng_metadata_printf(session
,
1946 "variant <_%s> {\n",
1947 type
->u
.variant
.tag_name
);
1950 nr_choices
= type
->u
.variant
.nr_choices
;
1951 for (i
= 0; i
< nr_choices
; i
++) {
1952 const struct lttng_event_field
*iter_field
;
1954 iter_field
= &type
->u
.variant
.choices
[i
];
1955 ret
= _lttng_field_statedump(session
, iter_field
, nesting
+ 1);
1959 ret
= print_tabs(session
, nesting
);
1962 ret
= lttng_metadata_printf(session
,
1968 * Must be called with sessions_mutex held.
1971 int _lttng_variant_statedump(struct lttng_session
*session
,
1972 const struct lttng_event_field
*field
,
1977 ret
= _lttng_variant_type_statedump(session
,
1978 &field
->type
, nesting
);
1981 ret
= lttng_metadata_printf(session
,
1988 * Must be called with sessions_mutex held.
1991 int _lttng_array_compound_statedump(struct lttng_session
*session
,
1992 const struct lttng_event_field
*field
,
1996 const struct lttng_type
*elem_type
;
1998 /* Only array of structures and variants are currently supported. */
1999 elem_type
= field
->type
.u
.array_compound
.elem_type
;
2000 switch (elem_type
->atype
) {
2002 ret
= _lttng_struct_type_statedump(session
, elem_type
, nesting
);
2007 ret
= _lttng_variant_type_statedump(session
, elem_type
, nesting
);
2014 ret
= lttng_metadata_printf(session
,
2017 field
->type
.u
.array_compound
.length
);
2022 * Must be called with sessions_mutex held.
2025 int _lttng_sequence_compound_statedump(struct lttng_session
*session
,
2026 const struct lttng_event_field
*field
,
2030 const char *length_name
;
2031 const struct lttng_type
*elem_type
;
2033 length_name
= field
->type
.u
.sequence_compound
.length_name
;
2035 /* Only array of structures and variants are currently supported. */
2036 elem_type
= field
->type
.u
.sequence_compound
.elem_type
;
2037 switch (elem_type
->atype
) {
2039 ret
= _lttng_struct_type_statedump(session
, elem_type
, nesting
);
2044 ret
= _lttng_variant_type_statedump(session
, elem_type
, nesting
);
2051 ret
= lttng_metadata_printf(session
,
2059 * Must be called with sessions_mutex held.
2062 int _lttng_enum_statedump(struct lttng_session
*session
,
2063 const struct lttng_event_field
*field
,
2066 const struct lttng_enum_desc
*enum_desc
;
2067 const struct lttng_integer_type
*container_type
;
2069 unsigned int i
, nr_entries
;
2071 enum_desc
= field
->type
.u
.basic
.enumeration
.desc
;
2072 container_type
= &field
->type
.u
.basic
.enumeration
.container_type
;
2073 nr_entries
= enum_desc
->nr_entries
;
2075 ret
= print_tabs(session
, nesting
);
2078 ret
= lttng_metadata_printf(session
,
2079 "enum : integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } {\n",
2080 container_type
->size
,
2081 container_type
->alignment
,
2082 container_type
->signedness
,
2083 (container_type
->encoding
== lttng_encode_none
)
2085 : (container_type
->encoding
== lttng_encode_UTF8
)
2088 container_type
->base
,
2089 #if __BYTE_ORDER == __BIG_ENDIAN
2090 container_type
->reverse_byte_order
? " byte_order = le;" : ""
2092 container_type
->reverse_byte_order
? " byte_order = be;" : ""
2097 /* Dump all entries */
2098 for (i
= 0; i
< nr_entries
; i
++) {
2099 const struct lttng_enum_entry
*entry
= &enum_desc
->entries
[i
];
2102 ret
= print_tabs(session
, nesting
+ 1);
2105 ret
= lttng_metadata_printf(session
,
2109 len
= strlen(entry
->string
);
2110 /* Escape the character '"' */
2111 for (j
= 0; j
< len
; j
++) {
2112 char c
= entry
->string
[j
];
2116 ret
= lttng_metadata_printf(session
,
2120 ret
= lttng_metadata_printf(session
,
2124 ret
= lttng_metadata_printf(session
,
2131 ret
= lttng_metadata_printf(session
, "\"");
2135 if (entry
->options
.is_auto
) {
2136 ret
= lttng_metadata_printf(session
, ",\n");
2140 ret
= lttng_metadata_printf(session
,
2144 if (entry
->start
.signedness
)
2145 ret
= lttng_metadata_printf(session
,
2146 "%lld", (long long) entry
->start
.value
);
2148 ret
= lttng_metadata_printf(session
,
2149 "%llu", entry
->start
.value
);
2152 if (entry
->start
.signedness
== entry
->end
.signedness
&&
2154 == entry
->end
.value
) {
2155 ret
= lttng_metadata_printf(session
,
2158 if (entry
->end
.signedness
) {
2159 ret
= lttng_metadata_printf(session
,
2161 (long long) entry
->end
.value
);
2163 ret
= lttng_metadata_printf(session
,
2172 ret
= print_tabs(session
, nesting
);
2175 ret
= lttng_metadata_printf(session
, "} _%s;\n",
2182 * Must be called with sessions_mutex held.
2185 int _lttng_field_statedump(struct lttng_session
*session
,
2186 const struct lttng_event_field
*field
,
2191 switch (field
->type
.atype
) {
2193 ret
= print_tabs(session
, nesting
);
2196 ret
= lttng_metadata_printf(session
,
2197 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n",
2198 field
->type
.u
.basic
.integer
.size
,
2199 field
->type
.u
.basic
.integer
.alignment
,
2200 field
->type
.u
.basic
.integer
.signedness
,
2201 (field
->type
.u
.basic
.integer
.encoding
== lttng_encode_none
)
2203 : (field
->type
.u
.basic
.integer
.encoding
== lttng_encode_UTF8
)
2206 field
->type
.u
.basic
.integer
.base
,
2207 #if __BYTE_ORDER == __BIG_ENDIAN
2208 field
->type
.u
.basic
.integer
.reverse_byte_order
? " byte_order = le;" : "",
2210 field
->type
.u
.basic
.integer
.reverse_byte_order
? " byte_order = be;" : "",
2215 ret
= _lttng_enum_statedump(session
, field
, nesting
);
2218 case atype_array_bitfield
:
2220 const struct lttng_basic_type
*elem_type
;
2222 elem_type
= &field
->type
.u
.array
.elem_type
;
2223 if (field
->type
.u
.array
.elem_alignment
) {
2224 ret
= print_tabs(session
, nesting
);
2227 ret
= lttng_metadata_printf(session
,
2228 "struct { } align(%u) _%s_padding;\n",
2229 field
->type
.u
.array
.elem_alignment
* CHAR_BIT
,
2234 ret
= print_tabs(session
, nesting
);
2237 ret
= lttng_metadata_printf(session
,
2238 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n",
2239 elem_type
->u
.basic
.integer
.size
,
2240 elem_type
->u
.basic
.integer
.alignment
,
2241 elem_type
->u
.basic
.integer
.signedness
,
2242 (elem_type
->u
.basic
.integer
.encoding
== lttng_encode_none
)
2244 : (elem_type
->u
.basic
.integer
.encoding
== lttng_encode_UTF8
)
2247 elem_type
->u
.basic
.integer
.base
,
2248 #if __BYTE_ORDER == __BIG_ENDIAN
2249 elem_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = le;" : "",
2251 elem_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = be;" : "",
2253 field
->name
, field
->type
.u
.array
.length
);
2256 case atype_sequence
:
2257 case atype_sequence_bitfield
:
2259 const struct lttng_basic_type
*elem_type
;
2260 const struct lttng_basic_type
*length_type
;
2262 elem_type
= &field
->type
.u
.sequence
.elem_type
;
2263 length_type
= &field
->type
.u
.sequence
.length_type
;
2264 ret
= print_tabs(session
, nesting
);
2267 ret
= lttng_metadata_printf(session
,
2268 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n",
2269 length_type
->u
.basic
.integer
.size
,
2270 (unsigned int) length_type
->u
.basic
.integer
.alignment
,
2271 length_type
->u
.basic
.integer
.signedness
,
2272 (length_type
->u
.basic
.integer
.encoding
== lttng_encode_none
)
2274 : ((length_type
->u
.basic
.integer
.encoding
== lttng_encode_UTF8
)
2277 length_type
->u
.basic
.integer
.base
,
2278 #if __BYTE_ORDER == __BIG_ENDIAN
2279 length_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = le;" : "",
2281 length_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = be;" : "",
2287 if (field
->type
.u
.sequence
.elem_alignment
) {
2288 ret
= print_tabs(session
, nesting
);
2291 ret
= lttng_metadata_printf(session
,
2292 "struct { } align(%u) _%s_padding;\n",
2293 field
->type
.u
.sequence
.elem_alignment
* CHAR_BIT
,
2298 ret
= print_tabs(session
, nesting
);
2301 ret
= lttng_metadata_printf(session
,
2302 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n",
2303 elem_type
->u
.basic
.integer
.size
,
2304 (unsigned int) elem_type
->u
.basic
.integer
.alignment
,
2305 elem_type
->u
.basic
.integer
.signedness
,
2306 (elem_type
->u
.basic
.integer
.encoding
== lttng_encode_none
)
2308 : ((elem_type
->u
.basic
.integer
.encoding
== lttng_encode_UTF8
)
2311 elem_type
->u
.basic
.integer
.base
,
2312 #if __BYTE_ORDER == __BIG_ENDIAN
2313 elem_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = le;" : "",
2315 elem_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = be;" : "",
2323 /* Default encoding is UTF8 */
2324 ret
= print_tabs(session
, nesting
);
2327 ret
= lttng_metadata_printf(session
,
2329 field
->type
.u
.basic
.string
.encoding
== lttng_encode_ASCII
?
2330 " { encoding = ASCII; }" : "",
2334 ret
= _lttng_struct_statedump(session
, field
, nesting
);
2336 case atype_array_compound
:
2337 ret
= _lttng_array_compound_statedump(session
, field
, nesting
);
2339 case atype_sequence_compound
:
2340 ret
= _lttng_sequence_compound_statedump(session
, field
, nesting
);
2343 ret
= _lttng_variant_statedump(session
, field
, nesting
);
2354 int _lttng_context_metadata_statedump(struct lttng_session
*session
,
2355 struct lttng_ctx
*ctx
)
2362 for (i
= 0; i
< ctx
->nr_fields
; i
++) {
2363 const struct lttng_ctx_field
*field
= &ctx
->fields
[i
];
2365 ret
= _lttng_field_statedump(session
, &field
->event_field
, 2);
2373 int _lttng_fields_metadata_statedump(struct lttng_session
*session
,
2374 struct lttng_event
*event
)
2376 const struct lttng_event_desc
*desc
= event
->desc
;
2380 for (i
= 0; i
< desc
->nr_fields
; i
++) {
2381 const struct lttng_event_field
*field
= &desc
->fields
[i
];
2383 ret
= _lttng_field_statedump(session
, field
, 2);
2391 * Must be called with sessions_mutex held.
2392 * The entire event metadata is printed as a single atomic metadata
2396 int _lttng_event_metadata_statedump(struct lttng_session
*session
,
2397 struct lttng_channel
*chan
,
2398 struct lttng_event
*event
)
2402 if (event
->metadata_dumped
|| !LTTNG_READ_ONCE(session
->active
))
2404 if (chan
->channel_type
== METADATA_CHANNEL
)
2407 lttng_metadata_begin(session
);
2409 ret
= lttng_metadata_printf(session
,
2413 " stream_id = %u;\n",
2421 ret
= lttng_metadata_printf(session
,
2422 " context := struct {\n");
2426 ret
= _lttng_context_metadata_statedump(session
, event
->ctx
);
2430 ret
= lttng_metadata_printf(session
,
2436 ret
= lttng_metadata_printf(session
,
2437 " fields := struct {\n"
2442 ret
= _lttng_fields_metadata_statedump(session
, event
);
2447 * LTTng space reservation can only reserve multiples of the
2450 ret
= lttng_metadata_printf(session
,
2456 event
->metadata_dumped
= 1;
2458 lttng_metadata_end(session
);
2464 * Must be called with sessions_mutex held.
2465 * The entire channel metadata is printed as a single atomic metadata
2469 int _lttng_channel_metadata_statedump(struct lttng_session
*session
,
2470 struct lttng_channel
*chan
)
2474 if (chan
->metadata_dumped
|| !LTTNG_READ_ONCE(session
->active
))
2477 if (chan
->channel_type
== METADATA_CHANNEL
)
2480 lttng_metadata_begin(session
);
2482 WARN_ON_ONCE(!chan
->header_type
);
2483 ret
= lttng_metadata_printf(session
,
2486 " event.header := %s;\n"
2487 " packet.context := struct packet_context;\n",
2489 chan
->header_type
== 1 ? "struct event_header_compact" :
2490 "struct event_header_large");
2495 ret
= lttng_metadata_printf(session
,
2496 " event.context := struct {\n");
2500 ret
= _lttng_context_metadata_statedump(session
, chan
->ctx
);
2504 ret
= lttng_metadata_printf(session
,
2510 ret
= lttng_metadata_printf(session
,
2513 chan
->metadata_dumped
= 1;
2515 lttng_metadata_end(session
);
2520 * Must be called with sessions_mutex held.
2523 int _lttng_stream_packet_context_declare(struct lttng_session
*session
)
2525 return lttng_metadata_printf(session
,
2526 "struct packet_context {\n"
2527 " uint64_clock_monotonic_t timestamp_begin;\n"
2528 " uint64_clock_monotonic_t timestamp_end;\n"
2529 " uint64_t content_size;\n"
2530 " uint64_t packet_size;\n"
2531 " uint64_t packet_seq_num;\n"
2532 " unsigned long events_discarded;\n"
2533 " uint32_t cpu_id;\n"
2540 * id: range: 0 - 30.
2541 * id 31 is reserved to indicate an extended header.
2544 * id: range: 0 - 65534.
2545 * id 65535 is reserved to indicate an extended header.
2547 * Must be called with sessions_mutex held.
2550 int _lttng_event_header_declare(struct lttng_session
*session
)
2552 return lttng_metadata_printf(session
,
2553 "struct event_header_compact {\n"
2554 " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n"
2557 " uint27_clock_monotonic_t timestamp;\n"
2561 " uint64_clock_monotonic_t timestamp;\n"
2566 "struct event_header_large {\n"
2567 " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n"
2570 " uint32_clock_monotonic_t timestamp;\n"
2574 " uint64_clock_monotonic_t timestamp;\n"
2578 lttng_alignof(uint32_t) * CHAR_BIT
,
2579 lttng_alignof(uint16_t) * CHAR_BIT
2584 * Approximation of NTP time of day to clock monotonic correlation,
2585 * taken at start of trace.
2586 * Yes, this is only an approximation. Yes, we can (and will) do better
2587 * in future versions.
2588 * This function may return a negative offset. It may happen if the
2589 * system sets the REALTIME clock to 0 after boot.
2591 * Use 64bit timespec on kernels that have it, this makes 32bit arch
2595 int64_t measure_clock_offset(void)
2597 uint64_t monotonic_avg
, monotonic
[2], realtime
;
2598 uint64_t tcf
= trace_clock_freq();
2600 unsigned long flags
;
2601 #ifdef LTTNG_KERNEL_HAS_TIMESPEC64
2602 struct timespec64 rts
= { 0, 0 };
2604 struct timespec rts
= { 0, 0 };
2607 /* Disable interrupts to increase correlation precision. */
2608 local_irq_save(flags
);
2609 monotonic
[0] = trace_clock_read64();
2610 #ifdef LTTNG_KERNEL_HAS_TIMESPEC64
2611 ktime_get_real_ts64(&rts
);
2613 getnstimeofday(&rts
);
2615 monotonic
[1] = trace_clock_read64();
2616 local_irq_restore(flags
);
2618 monotonic_avg
= (monotonic
[0] + monotonic
[1]) >> 1;
2619 realtime
= (uint64_t) rts
.tv_sec
* tcf
;
2620 if (tcf
== NSEC_PER_SEC
) {
2621 realtime
+= rts
.tv_nsec
;
2623 uint64_t n
= rts
.tv_nsec
* tcf
;
2625 do_div(n
, NSEC_PER_SEC
);
2628 offset
= (int64_t) realtime
- monotonic_avg
;
2633 int print_escaped_ctf_string(struct lttng_session
*session
, const char *string
)
2641 while (cur
!= '\0') {
2644 ret
= lttng_metadata_printf(session
, "%s", "\\n");
2648 ret
= lttng_metadata_printf(session
, "%c", '\\');
2651 /* We still print the current char */
2654 ret
= lttng_metadata_printf(session
, "%c", cur
);
2668 int print_metadata_escaped_field(struct lttng_session
*session
, const char *field
,
2669 const char *field_value
)
2673 ret
= lttng_metadata_printf(session
, " %s = \"", field
);
2677 ret
= print_escaped_ctf_string(session
, field_value
);
2681 ret
= lttng_metadata_printf(session
, "\";\n");
2688 * Output metadata into this session's metadata buffers.
2689 * Must be called with sessions_mutex held.
2692 int _lttng_session_metadata_statedump(struct lttng_session
*session
)
2694 unsigned char *uuid_c
= session
->uuid
.b
;
2695 unsigned char uuid_s
[37], clock_uuid_s
[BOOT_ID_LEN
];
2696 const char *product_uuid
;
2697 struct lttng_channel
*chan
;
2698 struct lttng_event
*event
;
2701 if (!LTTNG_READ_ONCE(session
->active
))
2704 lttng_metadata_begin(session
);
2706 if (session
->metadata_dumped
)
2709 snprintf(uuid_s
, sizeof(uuid_s
),
2710 "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
2711 uuid_c
[0], uuid_c
[1], uuid_c
[2], uuid_c
[3],
2712 uuid_c
[4], uuid_c
[5], uuid_c
[6], uuid_c
[7],
2713 uuid_c
[8], uuid_c
[9], uuid_c
[10], uuid_c
[11],
2714 uuid_c
[12], uuid_c
[13], uuid_c
[14], uuid_c
[15]);
2716 ret
= lttng_metadata_printf(session
,
2717 "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n"
2718 "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n"
2719 "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n"
2720 "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n"
2721 "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n"
2722 "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n"
2723 "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n"
2729 " byte_order = %s;\n"
2730 " packet.header := struct {\n"
2731 " uint32_t magic;\n"
2732 " uint8_t uuid[16];\n"
2733 " uint32_t stream_id;\n"
2734 " uint64_t stream_instance_id;\n"
2737 lttng_alignof(uint8_t) * CHAR_BIT
,
2738 lttng_alignof(uint16_t) * CHAR_BIT
,
2739 lttng_alignof(uint32_t) * CHAR_BIT
,
2740 lttng_alignof(uint64_t) * CHAR_BIT
,
2741 sizeof(unsigned long) * CHAR_BIT
,
2742 lttng_alignof(unsigned long) * CHAR_BIT
,
2746 #if __BYTE_ORDER == __BIG_ENDIAN
2755 ret
= lttng_metadata_printf(session
,
2757 " hostname = \"%s\";\n"
2758 " domain = \"kernel\";\n"
2759 " sysname = \"%s\";\n"
2760 " kernel_release = \"%s\";\n"
2761 " kernel_version = \"%s\";\n"
2762 " tracer_name = \"lttng-modules\";\n"
2763 " tracer_major = %d;\n"
2764 " tracer_minor = %d;\n"
2765 " tracer_patchlevel = %d;\n"
2766 " trace_buffering_scheme = \"global\";\n",
2767 current
->nsproxy
->uts_ns
->name
.nodename
,
2771 LTTNG_MODULES_MAJOR_VERSION
,
2772 LTTNG_MODULES_MINOR_VERSION
,
2773 LTTNG_MODULES_PATCHLEVEL_VERSION
2778 ret
= print_metadata_escaped_field(session
, "trace_name", session
->name
);
2781 ret
= print_metadata_escaped_field(session
, "trace_creation_datetime",
2782 session
->creation_time
);
2786 /* Add the product UUID to the 'env' section */
2787 product_uuid
= dmi_get_system_info(DMI_PRODUCT_UUID
);
2789 ret
= lttng_metadata_printf(session
,
2790 " product_uuid = \"%s\";\n",
2797 /* Close the 'env' section */
2798 ret
= lttng_metadata_printf(session
, "};\n\n");
2802 ret
= lttng_metadata_printf(session
,
2804 " name = \"%s\";\n",
2810 if (!trace_clock_uuid(clock_uuid_s
)) {
2811 ret
= lttng_metadata_printf(session
,
2812 " uuid = \"%s\";\n",
2819 ret
= lttng_metadata_printf(session
,
2820 " description = \"%s\";\n"
2821 " freq = %llu; /* Frequency, in Hz */\n"
2822 " /* clock value offset from Epoch is: offset * (1/freq) */\n"
2825 trace_clock_description(),
2826 (unsigned long long) trace_clock_freq(),
2827 (long long) measure_clock_offset()
2832 ret
= lttng_metadata_printf(session
,
2833 "typealias integer {\n"
2834 " size = 27; align = 1; signed = false;\n"
2835 " map = clock.%s.value;\n"
2836 "} := uint27_clock_monotonic_t;\n"
2838 "typealias integer {\n"
2839 " size = 32; align = %u; signed = false;\n"
2840 " map = clock.%s.value;\n"
2841 "} := uint32_clock_monotonic_t;\n"
2843 "typealias integer {\n"
2844 " size = 64; align = %u; signed = false;\n"
2845 " map = clock.%s.value;\n"
2846 "} := uint64_clock_monotonic_t;\n\n",
2848 lttng_alignof(uint32_t) * CHAR_BIT
,
2850 lttng_alignof(uint64_t) * CHAR_BIT
,
2856 ret
= _lttng_stream_packet_context_declare(session
);
2860 ret
= _lttng_event_header_declare(session
);
2865 list_for_each_entry(chan
, &session
->chan
, list
) {
2866 ret
= _lttng_channel_metadata_statedump(session
, chan
);
2871 list_for_each_entry(event
, &session
->events
, list
) {
2872 ret
= _lttng_event_metadata_statedump(session
, event
->chan
, event
);
2876 session
->metadata_dumped
= 1;
2878 lttng_metadata_end(session
);
2883 * lttng_transport_register - LTT transport registration
2884 * @transport: transport structure
2886 * Registers a transport which can be used as output to extract the data out of
2887 * LTTng. The module calling this registration function must ensure that no
2888 * trap-inducing code will be executed by the transport functions. E.g.
2889 * vmalloc_sync_mappings() must be called between a vmalloc and the moment the memory
2890 * is made visible to the transport function. This registration acts as a
2891 * vmalloc_sync_mappings. Therefore, only if the module allocates virtual memory
2892 * after its registration must it synchronize the TLBs.
2894 void lttng_transport_register(struct lttng_transport
*transport
)
2897 * Make sure no page fault can be triggered by the module about to be
2898 * registered. We deal with this here so we don't have to call
2899 * vmalloc_sync_mappings() in each module's init.
2901 wrapper_vmalloc_sync_mappings();
2903 mutex_lock(&sessions_mutex
);
2904 list_add_tail(&transport
->node
, <tng_transport_list
);
2905 mutex_unlock(&sessions_mutex
);
2907 EXPORT_SYMBOL_GPL(lttng_transport_register
);
2910 * lttng_transport_unregister - LTT transport unregistration
2911 * @transport: transport structure
2913 void lttng_transport_unregister(struct lttng_transport
*transport
)
2915 mutex_lock(&sessions_mutex
);
2916 list_del(&transport
->node
);
2917 mutex_unlock(&sessions_mutex
);
2919 EXPORT_SYMBOL_GPL(lttng_transport_unregister
);
2921 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0))
2923 enum cpuhp_state lttng_hp_prepare
;
2924 enum cpuhp_state lttng_hp_online
;
2926 static int lttng_hotplug_prepare(unsigned int cpu
, struct hlist_node
*node
)
2928 struct lttng_cpuhp_node
*lttng_node
;
2930 lttng_node
= container_of(node
, struct lttng_cpuhp_node
, node
);
2931 switch (lttng_node
->component
) {
2932 case LTTNG_RING_BUFFER_FRONTEND
:
2934 case LTTNG_RING_BUFFER_BACKEND
:
2935 return lttng_cpuhp_rb_backend_prepare(cpu
, lttng_node
);
2936 case LTTNG_RING_BUFFER_ITER
:
2938 case LTTNG_CONTEXT_PERF_COUNTERS
:
2945 static int lttng_hotplug_dead(unsigned int cpu
, struct hlist_node
*node
)
2947 struct lttng_cpuhp_node
*lttng_node
;
2949 lttng_node
= container_of(node
, struct lttng_cpuhp_node
, node
);
2950 switch (lttng_node
->component
) {
2951 case LTTNG_RING_BUFFER_FRONTEND
:
2952 return lttng_cpuhp_rb_frontend_dead(cpu
, lttng_node
);
2953 case LTTNG_RING_BUFFER_BACKEND
:
2955 case LTTNG_RING_BUFFER_ITER
:
2957 case LTTNG_CONTEXT_PERF_COUNTERS
:
2958 return lttng_cpuhp_perf_counter_dead(cpu
, lttng_node
);
2964 static int lttng_hotplug_online(unsigned int cpu
, struct hlist_node
*node
)
2966 struct lttng_cpuhp_node
*lttng_node
;
2968 lttng_node
= container_of(node
, struct lttng_cpuhp_node
, node
);
2969 switch (lttng_node
->component
) {
2970 case LTTNG_RING_BUFFER_FRONTEND
:
2971 return lttng_cpuhp_rb_frontend_online(cpu
, lttng_node
);
2972 case LTTNG_RING_BUFFER_BACKEND
:
2974 case LTTNG_RING_BUFFER_ITER
:
2975 return lttng_cpuhp_rb_iter_online(cpu
, lttng_node
);
2976 case LTTNG_CONTEXT_PERF_COUNTERS
:
2977 return lttng_cpuhp_perf_counter_online(cpu
, lttng_node
);
2983 static int lttng_hotplug_offline(unsigned int cpu
, struct hlist_node
*node
)
2985 struct lttng_cpuhp_node
*lttng_node
;
2987 lttng_node
= container_of(node
, struct lttng_cpuhp_node
, node
);
2988 switch (lttng_node
->component
) {
2989 case LTTNG_RING_BUFFER_FRONTEND
:
2990 return lttng_cpuhp_rb_frontend_offline(cpu
, lttng_node
);
2991 case LTTNG_RING_BUFFER_BACKEND
:
2993 case LTTNG_RING_BUFFER_ITER
:
2995 case LTTNG_CONTEXT_PERF_COUNTERS
:
3002 static int __init
lttng_init_cpu_hotplug(void)
3006 ret
= cpuhp_setup_state_multi(CPUHP_BP_PREPARE_DYN
, "lttng:prepare",
3007 lttng_hotplug_prepare
,
3008 lttng_hotplug_dead
);
3012 lttng_hp_prepare
= ret
;
3013 lttng_rb_set_hp_prepare(ret
);
3015 ret
= cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN
, "lttng:online",
3016 lttng_hotplug_online
,
3017 lttng_hotplug_offline
);
3019 cpuhp_remove_multi_state(lttng_hp_prepare
);
3020 lttng_hp_prepare
= 0;
3023 lttng_hp_online
= ret
;
3024 lttng_rb_set_hp_online(ret
);
3029 static void __exit
lttng_exit_cpu_hotplug(void)
3031 lttng_rb_set_hp_online(0);
3032 cpuhp_remove_multi_state(lttng_hp_online
);
3033 lttng_rb_set_hp_prepare(0);
3034 cpuhp_remove_multi_state(lttng_hp_prepare
);
3037 #else /* #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0)) */
3038 static int lttng_init_cpu_hotplug(void)
3042 static void lttng_exit_cpu_hotplug(void)
3045 #endif /* #else #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0)) */
3048 static int __init
lttng_events_init(void)
3052 ret
= wrapper_lttng_fixup_sig(THIS_MODULE
);
3055 ret
= wrapper_get_pfnblock_flags_mask_init();
3058 ret
= wrapper_get_pageblock_flags_mask_init();
3061 ret
= lttng_probes_init();
3064 ret
= lttng_context_init();
3067 ret
= lttng_tracepoint_init();
3070 event_cache
= KMEM_CACHE(lttng_event
, 0);
3075 ret
= lttng_abi_init();
3078 ret
= lttng_logger_init();
3081 ret
= lttng_init_cpu_hotplug();
3084 printk(KERN_NOTICE
"LTTng: Loaded modules v%s.%s.%s%s (%s)%s%s\n",
3085 __stringify(LTTNG_MODULES_MAJOR_VERSION
),
3086 __stringify(LTTNG_MODULES_MINOR_VERSION
),
3087 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION
),
3088 LTTNG_MODULES_EXTRAVERSION
,
3090 #ifdef LTTNG_EXTRA_VERSION_GIT
3091 LTTNG_EXTRA_VERSION_GIT
[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT
,
3095 #ifdef LTTNG_EXTRA_VERSION_NAME
3096 LTTNG_EXTRA_VERSION_NAME
[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME
);
3100 #ifdef CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM
3101 printk(KERN_NOTICE
"LTTng: Experimental bitwise enum enabled.\n");
3102 #endif /* CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM */
3106 lttng_logger_exit();
3110 kmem_cache_destroy(event_cache
);
3112 lttng_tracepoint_exit();
3114 lttng_context_exit();
3115 printk(KERN_NOTICE
"LTTng: Failed to load modules v%s.%s.%s%s (%s)%s%s\n",
3116 __stringify(LTTNG_MODULES_MAJOR_VERSION
),
3117 __stringify(LTTNG_MODULES_MINOR_VERSION
),
3118 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION
),
3119 LTTNG_MODULES_EXTRAVERSION
,
3121 #ifdef LTTNG_EXTRA_VERSION_GIT
3122 LTTNG_EXTRA_VERSION_GIT
[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT
,
3126 #ifdef LTTNG_EXTRA_VERSION_NAME
3127 LTTNG_EXTRA_VERSION_NAME
[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME
);
3134 module_init(lttng_events_init
);
3136 static void __exit
lttng_events_exit(void)
3138 struct lttng_session
*session
, *tmpsession
;
3140 lttng_exit_cpu_hotplug();
3141 lttng_logger_exit();
3143 list_for_each_entry_safe(session
, tmpsession
, &sessions
, list
)
3144 lttng_session_destroy(session
);
3145 kmem_cache_destroy(event_cache
);
3146 lttng_tracepoint_exit();
3147 lttng_context_exit();
3148 printk(KERN_NOTICE
"LTTng: Unloaded modules v%s.%s.%s%s (%s)%s%s\n",
3149 __stringify(LTTNG_MODULES_MAJOR_VERSION
),
3150 __stringify(LTTNG_MODULES_MINOR_VERSION
),
3151 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION
),
3152 LTTNG_MODULES_EXTRAVERSION
,
3154 #ifdef LTTNG_EXTRA_VERSION_GIT
3155 LTTNG_EXTRA_VERSION_GIT
[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT
,
3159 #ifdef LTTNG_EXTRA_VERSION_NAME
3160 LTTNG_EXTRA_VERSION_NAME
[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME
);
3166 module_exit(lttng_events_exit
);
3168 #include "extra_version/patches.i"
3169 #ifdef LTTNG_EXTRA_VERSION_GIT
3170 MODULE_INFO(extra_version_git
, LTTNG_EXTRA_VERSION_GIT
);
3172 #ifdef LTTNG_EXTRA_VERSION_NAME
3173 MODULE_INFO(extra_version_name
, LTTNG_EXTRA_VERSION_NAME
);
3175 MODULE_LICENSE("GPL and additional rights");
3176 MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
3177 MODULE_DESCRIPTION("LTTng tracer");
3178 MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION
) "."
3179 __stringify(LTTNG_MODULES_MINOR_VERSION
) "."
3180 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION
)
3181 LTTNG_MODULES_EXTRAVERSION
);