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
25 #include <urcu/list.h>
26 #include <urcu/hlist.h>
35 #include <lttng/ust-endian.h>
39 #include <urcu/compiler.h>
40 #include <urcu/uatomic.h>
41 #include <urcu/arch.h>
43 #include <lttng/tracepoint.h>
44 #include <lttng/ust-events.h>
46 #include <usterr-signal-safe.h>
50 #include "lttng-ust-uuid.h"
52 #include "tracepoint-internal.h"
53 #include "ltt-tracer.h"
54 #include "ltt-tracer-core.h"
56 #include "../libringbuffer/shm.h"
60 * The sessions mutex is the centralized mutex across UST tracing
61 * control and probe registration. All operations within this file are
62 * called by the communication thread, under ust_lock protection.
64 static pthread_mutex_t sessions_mutex
= PTHREAD_MUTEX_INITIALIZER
;
68 pthread_mutex_lock(&sessions_mutex
);
73 pthread_mutex_unlock(&sessions_mutex
);
76 static CDS_LIST_HEAD(sessions
);
79 * Wildcard list, containing the active wildcards.
80 * Protected by ust lock.
82 static CDS_LIST_HEAD(wildcard_list
);
85 * Pending probes hash table, containing the registered ltt events for
86 * which tracepoint probes are still missing. Protected by the sessions
89 #define PENDING_PROBE_HASH_BITS 6
90 #define PENDING_PROBE_HASH_SIZE (1 << PENDING_PROBE_HASH_BITS)
91 static struct cds_hlist_head pending_probe_table
[PENDING_PROBE_HASH_SIZE
];
93 struct ust_pending_probe
{
94 struct ltt_event
*event
;
95 struct cds_hlist_node node
;
96 enum lttng_ust_loglevel_type loglevel_type
;
101 static void _ltt_event_destroy(struct ltt_event
*event
);
102 static void _ltt_wildcard_destroy(struct session_wildcard
*sw
);
103 static void _ltt_channel_destroy(struct ltt_channel
*chan
);
104 static int _ltt_event_unregister(struct ltt_event
*event
);
106 int _ltt_event_metadata_statedump(struct ltt_session
*session
,
107 struct ltt_channel
*chan
,
108 struct ltt_event
*event
);
110 int _ltt_session_metadata_statedump(struct ltt_session
*session
);
112 int ltt_loglevel_match(const struct lttng_event_desc
*desc
,
113 enum lttng_ust_loglevel_type req_type
,
118 if (req_type
== LTTNG_UST_LOGLEVEL_ALL
)
121 ev_loglevel
= TRACE_DEFAULT
;
123 ev_loglevel
= *(*desc
->loglevel
);
125 case LTTNG_UST_LOGLEVEL_RANGE
:
126 if (ev_loglevel
<= req_loglevel
|| req_loglevel
== -1)
130 case LTTNG_UST_LOGLEVEL_SINGLE
:
131 if (ev_loglevel
== req_loglevel
|| req_loglevel
== -1)
135 case LTTNG_UST_LOGLEVEL_ALL
:
142 * Return wildcard for a given event name if the event name match the
143 * one of the wildcards.
144 * Must be called with ust lock held.
145 * Returns NULL if not present.
148 struct wildcard_entry
*match_wildcard(const struct lttng_event_desc
*desc
)
150 struct wildcard_entry
*e
;
152 cds_list_for_each_entry(e
, &wildcard_list
, list
) {
153 /* If only contain '*' */
154 if (strlen(e
->name
) == 1)
156 /* Compare excluding final '*' */
157 if (!strncmp(desc
->name
, e
->name
, strlen(e
->name
) - 1))
159 continue; /* goto next, no match */
161 if (ltt_loglevel_match(desc
,
166 /* no match, loop to next */
172 * called at event creation if probe is missing.
173 * called with session mutex held.
176 int add_pending_probe(struct ltt_event
*event
, const char *name
,
177 enum lttng_ust_loglevel_type loglevel_type
,
180 struct cds_hlist_head
*head
;
181 struct ust_pending_probe
*e
;
182 size_t name_len
= strlen(name
) + 1;
185 if (name_len
> LTTNG_UST_SYM_NAME_LEN
) {
186 WARN("Truncating tracepoint name %s which exceeds size limits of %u chars", name
, LTTNG_UST_SYM_NAME_LEN
);
187 name_len
= LTTNG_UST_SYM_NAME_LEN
;
189 hash
= jhash(name
, name_len
- 1, 0);
190 head
= &pending_probe_table
[hash
& (PENDING_PROBE_HASH_SIZE
- 1)];
191 e
= zmalloc(sizeof(struct ust_pending_probe
) + name_len
);
194 memcpy(&e
->name
[0], name
, name_len
);
195 e
->name
[name_len
- 1] = '\0';
196 e
->loglevel_type
= loglevel_type
;
197 e
->loglevel
= loglevel
;
198 cds_hlist_add_head(&e
->node
, head
);
200 event
->pending_probe
= e
;
205 * remove a pending probe. called when at event teardown and when an
206 * event is fixed (probe is loaded).
207 * called with session mutex held.
210 void remove_pending_probe(struct ust_pending_probe
*e
)
214 cds_hlist_del(&e
->node
);
219 * Called at library load: connect the probe on the events pending on
221 * called with session mutex held.
223 int pending_probe_fix_events(const struct lttng_event_desc
*desc
)
225 struct cds_hlist_head
*head
;
226 struct cds_hlist_node
*node
, *p
;
227 struct ust_pending_probe
*e
;
228 const char *name
= desc
->name
;
230 struct lttng_ust_event event_param
;
231 size_t name_len
= strlen(name
) + 1;
236 struct wildcard_entry
*wildcard
;
238 wildcard
= match_wildcard(desc
);
239 if (strcmp(desc
->name
, "lttng_ust:metadata") && wildcard
) {
240 struct session_wildcard
*sw
;
242 cds_list_for_each_entry(sw
, &wildcard
->session_list
,
244 struct ltt_event
*ev
;
247 memcpy(&event_param
, &sw
->event_param
,
248 sizeof(event_param
));
249 memcpy(event_param
.name
,
251 sizeof(event_param
.name
));
253 ret
= ltt_event_create(sw
->chan
,
256 DBG("Error creating event");
259 cds_list_add(&ev
->wildcard_list
,
261 lttng_filter_event_link_bytecode(ev
,
262 sw
->filter_bytecode
);
267 if (name_len
> LTTNG_UST_SYM_NAME_LEN
) {
268 WARN("Truncating tracepoint name %s which exceeds size limits of %u chars", name
, LTTNG_UST_SYM_NAME_LEN
);
269 name_len
= LTTNG_UST_SYM_NAME_LEN
;
271 hash
= jhash(name
, name_len
- 1, 0);
272 head
= &pending_probe_table
[hash
& (PENDING_PROBE_HASH_SIZE
- 1)];
273 cds_hlist_for_each_entry_safe(e
, node
, p
, head
, node
) {
274 struct ltt_event
*event
;
275 struct ltt_channel
*chan
;
277 if (!ltt_loglevel_match(desc
,
282 if (strncmp(name
, e
->name
, LTTNG_UST_SYM_NAME_LEN
- 1)) {
287 assert(!event
->desc
);
289 event
->pending_probe
= NULL
;
290 remove_pending_probe(e
);
291 ret
|= __tracepoint_probe_register(name
,
292 event
->desc
->probe_callback
,
293 event
, event
->desc
->signature
);
296 event
->id
= chan
->free_event_id
++;
297 ret
|= _ltt_event_metadata_statedump(chan
->session
, chan
,
299 lttng_filter_event_link_bytecode(event
,
300 event
->filter_bytecode
);
305 void synchronize_trace(void)
310 struct ltt_session
*ltt_session_create(void)
312 struct ltt_session
*session
;
315 session
= zmalloc(sizeof(struct ltt_session
));
318 CDS_INIT_LIST_HEAD(&session
->chan
);
319 CDS_INIT_LIST_HEAD(&session
->events
);
320 CDS_INIT_LIST_HEAD(&session
->wildcards
);
321 ret
= lttng_ust_uuid_generate(session
->uuid
);
323 session
->uuid
[0] = '\0';
325 cds_list_add(&session
->list
, &sessions
);
329 void ltt_session_destroy(struct ltt_session
*session
)
331 struct ltt_channel
*chan
, *tmpchan
;
332 struct ltt_event
*event
, *tmpevent
;
333 struct session_wildcard
*wildcard
, *tmpwildcard
;
336 CMM_ACCESS_ONCE(session
->active
) = 0;
337 cds_list_for_each_entry(event
, &session
->events
, list
) {
338 ret
= _ltt_event_unregister(event
);
341 synchronize_trace(); /* Wait for in-flight events to complete */
342 cds_list_for_each_entry_safe(wildcard
, tmpwildcard
, &session
->wildcards
, list
)
343 _ltt_wildcard_destroy(wildcard
);
344 cds_list_for_each_entry_safe(event
, tmpevent
, &session
->events
, list
)
345 _ltt_event_destroy(event
);
346 cds_list_for_each_entry_safe(chan
, tmpchan
, &session
->chan
, list
)
347 _ltt_channel_destroy(chan
);
348 cds_list_del(&session
->list
);
352 int ltt_session_enable(struct ltt_session
*session
)
355 struct ltt_channel
*chan
;
357 if (session
->active
) {
363 * Snapshot the number of events per channel to know the type of header
366 cds_list_for_each_entry(chan
, &session
->chan
, list
) {
367 if (chan
->header_type
)
368 continue; /* don't change it if session stop/restart */
369 if (chan
->free_event_id
< 31)
370 chan
->header_type
= 1; /* compact */
372 chan
->header_type
= 2; /* large */
375 CMM_ACCESS_ONCE(session
->active
) = 1;
376 CMM_ACCESS_ONCE(session
->been_active
) = 1;
377 ret
= _ltt_session_metadata_statedump(session
);
379 CMM_ACCESS_ONCE(session
->active
) = 0;
384 int ltt_session_disable(struct ltt_session
*session
)
388 if (!session
->active
) {
392 CMM_ACCESS_ONCE(session
->active
) = 0;
397 int ltt_channel_enable(struct ltt_channel
*channel
)
401 if (channel
== channel
->session
->metadata
)
403 old
= uatomic_xchg(&channel
->enabled
, 1);
409 int ltt_channel_disable(struct ltt_channel
*channel
)
413 if (channel
== channel
->session
->metadata
)
415 old
= uatomic_xchg(&channel
->enabled
, 0);
421 int ltt_event_enable(struct ltt_event
*event
)
425 if (event
->chan
== event
->chan
->session
->metadata
)
427 old
= uatomic_xchg(&event
->enabled
, 1);
433 int ltt_event_disable(struct ltt_event
*event
)
437 if (event
->chan
== event
->chan
->session
->metadata
)
439 old
= uatomic_xchg(&event
->enabled
, 0);
445 struct ltt_channel
*ltt_channel_create(struct ltt_session
*session
,
446 const char *transport_name
,
448 size_t subbuf_size
, size_t num_subbuf
,
449 unsigned int switch_timer_interval
,
450 unsigned int read_timer_interval
,
451 int **shm_fd
, int **wait_fd
,
452 uint64_t **memory_map_size
,
453 struct ltt_channel
*chan_priv_init
)
455 struct ltt_channel
*chan
= NULL
;
456 struct ltt_transport
*transport
;
458 if (session
->been_active
)
459 goto active
; /* Refuse to add channel to active session */
460 transport
= ltt_transport_find(transport_name
);
462 DBG("LTTng transport %s not found\n",
466 chan_priv_init
->id
= session
->free_chan_id
++;
467 chan_priv_init
->session
= session
;
469 * Note: the channel creation op already writes into the packet
470 * headers. Therefore the "chan" information used as input
471 * should be already accessible.
473 chan
= transport
->ops
.channel_create(transport_name
, buf_addr
,
474 subbuf_size
, num_subbuf
, switch_timer_interval
,
475 read_timer_interval
, shm_fd
, wait_fd
,
476 memory_map_size
, chan_priv_init
);
480 chan
->ops
= &transport
->ops
;
481 cds_list_add(&chan
->list
, &session
->chan
);
491 * Only used internally at session destruction.
494 void _ltt_channel_destroy(struct ltt_channel
*chan
)
496 cds_list_del(&chan
->list
);
497 lttng_destroy_context(chan
->ctx
);
498 chan
->ops
->channel_destroy(chan
);
502 * Supports event creation while tracing session is active.
504 int ltt_event_create(struct ltt_channel
*chan
,
505 struct lttng_ust_event
*event_param
,
506 struct ltt_event
**_event
)
508 const struct lttng_event_desc
*desc
= NULL
; /* silence gcc */
509 struct ltt_event
*event
;
512 if (chan
->used_event_id
== -1U) {
517 * This is O(n^2) (for each event, the loop is called at event
518 * creation). Might require a hash if we have lots of events.
520 cds_list_for_each_entry(event
, &chan
->session
->events
, list
) {
521 if (event
->desc
&& !strncmp(event
->desc
->name
,
523 LTTNG_UST_SYM_NAME_LEN
- 1)) {
530 * Check if loglevel match. Refuse to connect event if not.
532 if (event_param
->instrumentation
== LTTNG_UST_TRACEPOINT
) {
533 desc
= ltt_event_get(event_param
->name
);
535 if (!ltt_loglevel_match(desc
,
536 event_param
->loglevel_type
,
537 event_param
->loglevel
)) {
539 goto no_loglevel_match
;
543 * If descriptor is not there, it will be added to
547 event
= zmalloc(sizeof(struct ltt_event
));
554 * used_event_id counts the maximum number of event IDs that can
555 * register if all probes register.
557 chan
->used_event_id
++;
559 event
->instrumentation
= event_param
->instrumentation
;
560 /* Populate ltt_event structure before tracepoint registration. */
562 switch (event_param
->instrumentation
) {
563 case LTTNG_UST_TRACEPOINT
:
566 ret
= __tracepoint_probe_register(event_param
->name
,
567 event
->desc
->probe_callback
,
568 event
, event
->desc
->signature
);
571 event
->id
= chan
->free_event_id
++;
574 * If the probe is not present, event->desc stays NULL,
575 * waiting for the probe to register, and the event->id
578 ret
= add_pending_probe(event
, event_param
->name
,
579 event_param
->loglevel_type
,
580 event_param
->loglevel
);
582 goto add_pending_error
;
589 ret
= _ltt_event_metadata_statedump(chan
->session
, chan
, event
);
591 goto statedump_error
;
593 cds_list_add(&event
->list
, &chan
->session
->events
);
599 WARN_ON_ONCE(__tracepoint_probe_unregister(event_param
->name
,
600 event
->desc
->probe_callback
,
602 ltt_event_put(event
->desc
);
615 * Only used internally at session destruction.
617 int _ltt_event_unregister(struct ltt_event
*event
)
621 switch (event
->instrumentation
) {
622 case LTTNG_UST_TRACEPOINT
:
624 ret
= __tracepoint_probe_unregister(event
->desc
->name
,
625 event
->desc
->probe_callback
,
630 remove_pending_probe(event
->pending_probe
);
641 * Only used internally at session destruction.
644 void _ltt_event_destroy(struct ltt_event
*event
)
646 switch (event
->instrumentation
) {
647 case LTTNG_UST_TRACEPOINT
:
649 ltt_event_put(event
->desc
);
655 cds_list_del(&event
->list
);
656 lttng_destroy_context(event
->ctx
);
657 free(event
->filter_bytecode
);
658 free(event
->filter_data
);
663 * We have exclusive access to our metadata buffer (protected by the
664 * ust_lock), so we can do racy operations such as looking for
665 * remaining space left in packet and write, since mutual exclusion
666 * protects us from concurrent writes.
668 int lttng_metadata_printf(struct ltt_session
*session
,
669 const char *fmt
, ...)
671 struct lttng_ust_lib_ring_buffer_ctx ctx
;
672 struct ltt_channel
*chan
= session
->metadata
;
674 int ret
= 0, waitret
;
675 size_t len
, reserve_len
, pos
;
678 WARN_ON_ONCE(!CMM_ACCESS_ONCE(session
->active
));
681 ret
= vasprintf(&str
, fmt
, ap
);
689 for (pos
= 0; pos
< len
; pos
+= reserve_len
) {
690 reserve_len
= min_t(size_t,
691 chan
->ops
->packet_avail_size(chan
->chan
, chan
->handle
),
693 lib_ring_buffer_ctx_init(&ctx
, chan
->chan
, NULL
, reserve_len
,
694 sizeof(char), -1, chan
->handle
);
696 * We don't care about metadata buffer's records lost
697 * count, because we always retry here. Report error if
698 * we need to bail out after timeout or being
701 waitret
= wait_cond_interruptible_timeout(
703 ret
= chan
->ops
->event_reserve(&ctx
, 0);
704 ret
!= -ENOBUFS
|| !ret
;
706 LTTNG_METADATA_TIMEOUT_MSEC
);
707 if (waitret
== -ETIMEDOUT
|| waitret
== -EINTR
|| ret
) {
708 DBG("LTTng: Failure to write metadata to buffers (%s)\n",
709 waitret
== -EINTR
? "interrupted" :
710 (ret
== -ENOBUFS
? "timeout" : "I/O error"));
711 if (waitret
== -EINTR
)
715 chan
->ops
->event_write(&ctx
, &str
[pos
], reserve_len
);
716 chan
->ops
->event_commit(&ctx
);
724 int _ltt_field_statedump(struct ltt_session
*session
,
725 const struct lttng_event_field
*field
)
732 switch (field
->type
.atype
) {
734 ret
= lttng_metadata_printf(session
,
735 " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s;\n",
736 field
->type
.u
.basic
.integer
.size
,
737 field
->type
.u
.basic
.integer
.alignment
,
738 field
->type
.u
.basic
.integer
.signedness
,
739 (field
->type
.u
.basic
.integer
.encoding
== lttng_encode_none
)
741 : (field
->type
.u
.basic
.integer
.encoding
== lttng_encode_UTF8
)
744 field
->type
.u
.basic
.integer
.base
,
745 #if (BYTE_ORDER == BIG_ENDIAN)
746 field
->type
.u
.basic
.integer
.reverse_byte_order
? " byte_order = le;" : "",
748 field
->type
.u
.basic
.integer
.reverse_byte_order
? " byte_order = be;" : "",
753 ret
= lttng_metadata_printf(session
,
754 " floating_point { exp_dig = %u; mant_dig = %u; align = %u;%s } _%s;\n",
755 field
->type
.u
.basic
._float
.exp_dig
,
756 field
->type
.u
.basic
._float
.mant_dig
,
757 field
->type
.u
.basic
._float
.alignment
,
758 #if (BYTE_ORDER == BIG_ENDIAN)
759 field
->type
.u
.basic
.integer
.reverse_byte_order
? " byte_order = le;" : "",
761 field
->type
.u
.basic
.integer
.reverse_byte_order
? " byte_order = be;" : "",
766 ret
= lttng_metadata_printf(session
,
768 field
->type
.u
.basic
.enumeration
.name
,
773 const struct lttng_basic_type
*elem_type
;
775 elem_type
= &field
->type
.u
.array
.elem_type
;
776 ret
= lttng_metadata_printf(session
,
777 " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[%u];\n",
778 elem_type
->u
.basic
.integer
.size
,
779 elem_type
->u
.basic
.integer
.alignment
,
780 elem_type
->u
.basic
.integer
.signedness
,
781 (elem_type
->u
.basic
.integer
.encoding
== lttng_encode_none
)
783 : (elem_type
->u
.basic
.integer
.encoding
== lttng_encode_UTF8
)
786 elem_type
->u
.basic
.integer
.base
,
787 #if (BYTE_ORDER == BIG_ENDIAN)
788 elem_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = le;" : "",
790 elem_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = be;" : "",
792 field
->name
, field
->type
.u
.array
.length
);
797 const struct lttng_basic_type
*elem_type
;
798 const struct lttng_basic_type
*length_type
;
800 elem_type
= &field
->type
.u
.sequence
.elem_type
;
801 length_type
= &field
->type
.u
.sequence
.length_type
;
802 ret
= lttng_metadata_printf(session
,
803 " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } __%s_length;\n",
804 length_type
->u
.basic
.integer
.size
,
805 (unsigned int) length_type
->u
.basic
.integer
.alignment
,
806 length_type
->u
.basic
.integer
.signedness
,
807 (length_type
->u
.basic
.integer
.encoding
== lttng_encode_none
)
809 : ((length_type
->u
.basic
.integer
.encoding
== lttng_encode_UTF8
)
812 length_type
->u
.basic
.integer
.base
,
813 #if (BYTE_ORDER == BIG_ENDIAN)
814 length_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = le;" : "",
816 length_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = be;" : "",
822 ret
= lttng_metadata_printf(session
,
823 " integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s } _%s[ __%s_length ];\n",
824 elem_type
->u
.basic
.integer
.size
,
825 (unsigned int) elem_type
->u
.basic
.integer
.alignment
,
826 elem_type
->u
.basic
.integer
.signedness
,
827 (elem_type
->u
.basic
.integer
.encoding
== lttng_encode_none
)
829 : ((elem_type
->u
.basic
.integer
.encoding
== lttng_encode_UTF8
)
832 elem_type
->u
.basic
.integer
.base
,
833 #if (BYTE_ORDER == BIG_ENDIAN)
834 elem_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = le;" : "",
836 elem_type
->u
.basic
.integer
.reverse_byte_order
? " byte_order = be;" : "",
844 /* Default encoding is UTF8 */
845 ret
= lttng_metadata_printf(session
,
847 field
->type
.u
.basic
.string
.encoding
== lttng_encode_ASCII
?
848 " { encoding = ASCII; }" : "",
859 int _ltt_context_metadata_statedump(struct ltt_session
*session
,
860 struct lttng_ctx
*ctx
)
867 for (i
= 0; i
< ctx
->nr_fields
; i
++) {
868 const struct lttng_ctx_field
*field
= &ctx
->fields
[i
];
870 ret
= _ltt_field_statedump(session
, &field
->event_field
);
878 int _ltt_fields_metadata_statedump(struct ltt_session
*session
,
879 struct ltt_event
*event
)
881 const struct lttng_event_desc
*desc
= event
->desc
;
885 for (i
= 0; i
< desc
->nr_fields
; i
++) {
886 const struct lttng_event_field
*field
= &desc
->fields
[i
];
888 ret
= _ltt_field_statedump(session
, field
);
896 int _ltt_event_metadata_statedump(struct ltt_session
*session
,
897 struct ltt_channel
*chan
,
898 struct ltt_event
*event
)
901 int loglevel
= TRACE_DEFAULT
;
903 if (event
->metadata_dumped
|| !CMM_ACCESS_ONCE(session
->active
))
905 if (chan
== session
->metadata
)
908 * Don't print events for which probe load is pending.
913 ret
= lttng_metadata_printf(session
,
917 " stream_id = %u;\n",
924 if (event
->desc
->loglevel
)
925 loglevel
= *(*event
->desc
->loglevel
);
927 ret
= lttng_metadata_printf(session
,
934 ret
= lttng_metadata_printf(session
,
935 " context := struct {\n");
939 ret
= _ltt_context_metadata_statedump(session
, event
->ctx
);
943 ret
= lttng_metadata_printf(session
,
949 ret
= lttng_metadata_printf(session
,
950 " fields := struct {\n"
955 ret
= _ltt_fields_metadata_statedump(session
, event
);
960 * LTTng space reservation can only reserve multiples of the
963 ret
= lttng_metadata_printf(session
,
969 event
->metadata_dumped
= 1;
976 int _ltt_channel_metadata_statedump(struct ltt_session
*session
,
977 struct ltt_channel
*chan
)
981 if (chan
->metadata_dumped
|| !CMM_ACCESS_ONCE(session
->active
))
983 if (chan
== session
->metadata
)
986 WARN_ON_ONCE(!chan
->header_type
);
987 ret
= lttng_metadata_printf(session
,
990 " event.header := %s;\n"
991 " packet.context := struct packet_context;\n",
993 chan
->header_type
== 1 ? "struct event_header_compact" :
994 "struct event_header_large");
999 ret
= lttng_metadata_printf(session
,
1000 " event.context := struct {\n");
1004 ret
= _ltt_context_metadata_statedump(session
, chan
->ctx
);
1008 ret
= lttng_metadata_printf(session
,
1014 ret
= lttng_metadata_printf(session
,
1017 chan
->metadata_dumped
= 1;
1023 int _ltt_stream_packet_context_declare(struct ltt_session
*session
)
1025 return lttng_metadata_printf(session
,
1026 "struct packet_context {\n"
1027 " uint64_clock_monotonic_t timestamp_begin;\n"
1028 " uint64_clock_monotonic_t timestamp_end;\n"
1029 " unsigned long events_discarded;\n"
1030 " uint32_t content_size;\n"
1031 " uint32_t packet_size;\n"
1032 " uint32_t cpu_id;\n"
1039 * id: range: 0 - 30.
1040 * id 31 is reserved to indicate an extended header.
1043 * id: range: 0 - 65534.
1044 * id 65535 is reserved to indicate an extended header.
1047 int _ltt_event_header_declare(struct ltt_session
*session
)
1049 return lttng_metadata_printf(session
,
1050 "struct event_header_compact {\n"
1051 " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n"
1054 " uint27_clock_monotonic_t timestamp;\n"
1058 " uint64_clock_monotonic_t timestamp;\n"
1063 "struct event_header_large {\n"
1064 " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n"
1067 " uint32_clock_monotonic_t timestamp;\n"
1071 " uint64_clock_monotonic_t timestamp;\n"
1075 lttng_alignof(uint32_t) * CHAR_BIT
,
1076 lttng_alignof(uint16_t) * CHAR_BIT
1081 * Approximation of NTP time of day to clock monotonic correlation,
1082 * taken at start of trace.
1083 * Yes, this is only an approximation. Yes, we can (and will) do better
1084 * in future versions.
1087 uint64_t measure_clock_offset(void)
1089 uint64_t offset
, monotonic
[2], realtime
;
1090 struct timespec rts
= { 0, 0 };
1093 monotonic
[0] = trace_clock_read64();
1094 ret
= clock_gettime(CLOCK_REALTIME
, &rts
);
1097 monotonic
[1] = trace_clock_read64();
1098 offset
= (monotonic
[0] + monotonic
[1]) >> 1;
1099 realtime
= (uint64_t) rts
.tv_sec
* 1000000000ULL;
1100 realtime
+= rts
.tv_nsec
;
1101 offset
= realtime
- offset
;
1106 * Output metadata into this session's metadata buffers.
1109 int _ltt_session_metadata_statedump(struct ltt_session
*session
)
1111 unsigned char *uuid_c
= session
->uuid
;
1112 char uuid_s
[LTTNG_UST_UUID_STR_LEN
],
1113 clock_uuid_s
[LTTNG_UST_UUID_STR_LEN
];
1114 struct ltt_channel
*chan
;
1115 struct ltt_event
*event
;
1117 char procname
[LTTNG_UST_PROCNAME_LEN
] = "";
1119 if (!CMM_ACCESS_ONCE(session
->active
))
1121 if (session
->metadata_dumped
)
1123 if (!session
->metadata
) {
1124 DBG("LTTng: attempt to start tracing, but metadata channel is not found. Operation abort.\n");
1128 snprintf(uuid_s
, sizeof(uuid_s
),
1129 "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
1130 uuid_c
[0], uuid_c
[1], uuid_c
[2], uuid_c
[3],
1131 uuid_c
[4], uuid_c
[5], uuid_c
[6], uuid_c
[7],
1132 uuid_c
[8], uuid_c
[9], uuid_c
[10], uuid_c
[11],
1133 uuid_c
[12], uuid_c
[13], uuid_c
[14], uuid_c
[15]);
1135 ret
= lttng_metadata_printf(session
,
1136 "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n"
1137 "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n"
1138 "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n"
1139 "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n"
1140 "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n"
1141 "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n"
1142 "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n"
1148 " byte_order = %s;\n"
1149 " packet.header := struct {\n"
1150 " uint32_t magic;\n"
1151 " uint8_t uuid[16];\n"
1152 " uint32_t stream_id;\n"
1155 lttng_alignof(uint8_t) * CHAR_BIT
,
1156 lttng_alignof(uint16_t) * CHAR_BIT
,
1157 lttng_alignof(uint32_t) * CHAR_BIT
,
1158 lttng_alignof(uint64_t) * CHAR_BIT
,
1159 sizeof(unsigned long) * CHAR_BIT
,
1160 lttng_alignof(unsigned long) * CHAR_BIT
,
1164 #if (BYTE_ORDER == BIG_ENDIAN)
1173 /* ignore error, just use empty string if error. */
1174 lttng_ust_getprocname(procname
);
1175 procname
[LTTNG_UST_PROCNAME_LEN
- 1] = '\0';
1176 ret
= lttng_metadata_printf(session
,
1179 " procname = \"%s\";\n"
1180 " domain = \"ust\";\n"
1181 " tracer_name = \"lttng-ust\";\n"
1182 " tracer_major = %u;\n"
1183 " tracer_minor = %u;\n"
1184 " tracer_patchlevel = %u;\n"
1188 LTTNG_UST_MAJOR_VERSION
,
1189 LTTNG_UST_MINOR_VERSION
,
1190 LTTNG_UST_PATCHLEVEL_VERSION
1195 ret
= lttng_metadata_printf(session
,
1203 if (!trace_clock_uuid(clock_uuid_s
)) {
1204 ret
= lttng_metadata_printf(session
,
1205 " uuid = \"%s\";\n",
1212 ret
= lttng_metadata_printf(session
,
1213 " description = \"Monotonic Clock\";\n"
1214 " freq = %" PRIu64
"; /* Frequency, in Hz */\n"
1215 " /* clock value offset from Epoch is: offset * (1/freq) */\n"
1216 " offset = %" PRIu64
";\n"
1219 measure_clock_offset()
1224 ret
= lttng_metadata_printf(session
,
1225 "typealias integer {\n"
1226 " size = 27; align = 1; signed = false;\n"
1227 " map = clock.monotonic.value;\n"
1228 "} := uint27_clock_monotonic_t;\n"
1230 "typealias integer {\n"
1231 " size = 32; align = %u; signed = false;\n"
1232 " map = clock.monotonic.value;\n"
1233 "} := uint32_clock_monotonic_t;\n"
1235 "typealias integer {\n"
1236 " size = 64; align = %u; signed = false;\n"
1237 " map = clock.monotonic.value;\n"
1238 "} := uint64_clock_monotonic_t;\n\n",
1239 lttng_alignof(uint32_t) * CHAR_BIT
,
1240 lttng_alignof(uint64_t) * CHAR_BIT
1245 ret
= _ltt_stream_packet_context_declare(session
);
1249 ret
= _ltt_event_header_declare(session
);
1254 cds_list_for_each_entry(chan
, &session
->chan
, list
) {
1255 ret
= _ltt_channel_metadata_statedump(session
, chan
);
1260 cds_list_for_each_entry(event
, &session
->events
, list
) {
1261 ret
= _ltt_event_metadata_statedump(session
, event
->chan
, event
);
1265 session
->metadata_dumped
= 1;
1270 void lttng_ust_events_exit(void)
1272 struct ltt_session
*session
, *tmpsession
;
1274 cds_list_for_each_entry_safe(session
, tmpsession
, &sessions
, list
)
1275 ltt_session_destroy(session
);
1281 int wildcard_same_loglevel(struct wildcard_entry
*e
,
1282 enum lttng_ust_loglevel_type loglevel_type
,
1285 if (e
->loglevel_type
== loglevel_type
&& e
->loglevel
== loglevel
)
1293 int wildcard_is_within(struct wildcard_entry
*e
,
1294 enum lttng_ust_loglevel_type loglevel_type
,
1297 if (e
->loglevel_type
== LTTNG_UST_LOGLEVEL_ALL
1298 || e
->loglevel
== -1)
1300 switch (e
->loglevel_type
) {
1301 case LTTNG_UST_LOGLEVEL_RANGE
:
1302 switch (loglevel_type
) {
1303 case LTTNG_UST_LOGLEVEL_RANGE
:
1304 if (e
->loglevel
>= loglevel
)
1308 case LTTNG_UST_LOGLEVEL_SINGLE
:
1309 if (e
->loglevel
<= 0 && loglevel
== 0)
1314 case LTTNG_UST_LOGLEVEL_SINGLE
:
1315 switch (loglevel_type
) {
1316 case LTTNG_UST_LOGLEVEL_RANGE
:
1321 case LTTNG_UST_LOGLEVEL_SINGLE
:
1322 if (e
->loglevel
== loglevel
)
1332 * Add the wildcard to the wildcard list. Must be called with
1336 struct session_wildcard
*add_wildcard(struct ltt_channel
*chan
,
1337 struct lttng_ust_event
*event_param
)
1339 struct wildcard_entry
*e
;
1340 struct session_wildcard
*sw
;
1341 size_t name_len
= strlen(event_param
->name
) + 1;
1345 * Try to find global wildcard entry. Given that this is shared
1346 * across all sessions, we need to check for exact loglevel
1347 * match, not just whether contained within the existing ones.
1349 cds_list_for_each_entry(e
, &wildcard_list
, list
) {
1350 if (!strncmp(event_param
->name
, e
->name
,
1351 LTTNG_UST_SYM_NAME_LEN
- 1)) {
1352 if (wildcard_same_loglevel(e
,
1353 event_param
->loglevel_type
,
1354 event_param
->loglevel
)) {
1363 * Create global wildcard entry if not found. Using
1364 * zmalloc here to allocate a variable length element.
1365 * Could cause some memory fragmentation if overused.
1367 e
= zmalloc(sizeof(struct wildcard_entry
) + name_len
);
1369 return ERR_PTR(-ENOMEM
);
1370 memcpy(&e
->name
[0], event_param
->name
, name_len
);
1371 e
->loglevel_type
= event_param
->loglevel_type
;
1372 e
->loglevel
= event_param
->loglevel
;
1373 cds_list_add(&e
->list
, &wildcard_list
);
1374 CDS_INIT_LIST_HEAD(&e
->session_list
);
1377 /* session wildcard */
1378 cds_list_for_each_entry(sw
, &e
->session_list
, session_list
) {
1379 if (chan
== sw
->chan
) {
1380 DBG("wildcard %s busy for this channel",
1382 return ERR_PTR(-EEXIST
); /* Already there */
1385 sw
= zmalloc(sizeof(struct session_wildcard
));
1387 return ERR_PTR(-ENOMEM
);
1390 memcpy(&sw
->event_param
, event_param
, sizeof(sw
->event_param
));
1391 sw
->event_param
.instrumentation
= LTTNG_UST_TRACEPOINT
;
1392 sw
->event_param
.loglevel_type
= event_param
->loglevel_type
;
1393 sw
->event_param
.loglevel
= event_param
->loglevel
;
1394 CDS_INIT_LIST_HEAD(&sw
->events
);
1395 cds_list_add(&sw
->list
, &chan
->session
->wildcards
);
1396 cds_list_add(&sw
->session_list
, &e
->session_list
);
1398 ltt_probes_create_wildcard_events(e
, sw
);
1403 * Remove the wildcard from the wildcard list. Must be called with
1404 * ust_lock held. Only called at session teardown.
1407 void _remove_wildcard(struct session_wildcard
*wildcard
)
1409 struct ltt_event
*ev
, *tmp
;
1412 * Just remove the events owned (for enable/disable) by this
1413 * wildcard from the list. The session teardown will take care
1414 * of freeing the event memory.
1416 cds_list_for_each_entry_safe(ev
, tmp
, &wildcard
->events
,
1418 cds_list_del(&ev
->wildcard_list
);
1420 cds_list_del(&wildcard
->session_list
);
1421 cds_list_del(&wildcard
->list
);
1422 if (cds_list_empty(&wildcard
->entry
->session_list
)) {
1423 cds_list_del(&wildcard
->entry
->list
);
1424 free(wildcard
->entry
);
1426 free(wildcard
->filter_bytecode
);
1430 int ltt_wildcard_create(struct ltt_channel
*chan
,
1431 struct lttng_ust_event
*event_param
,
1432 struct session_wildcard
**_sw
)
1434 struct session_wildcard
*sw
;
1436 sw
= add_wildcard(chan
, event_param
);
1437 if (!sw
|| IS_ERR(sw
)) {
1445 void _ltt_wildcard_destroy(struct session_wildcard
*sw
)
1447 _remove_wildcard(sw
);
1450 int ltt_wildcard_enable(struct session_wildcard
*wildcard
)
1452 struct ltt_event
*ev
;
1455 if (wildcard
->enabled
)
1457 cds_list_for_each_entry(ev
, &wildcard
->events
, wildcard_list
) {
1458 ret
= ltt_event_enable(ev
);
1460 DBG("Error: enable error.\n");
1464 wildcard
->enabled
= 1;
1468 int ltt_wildcard_disable(struct session_wildcard
*wildcard
)
1470 struct ltt_event
*ev
;
1473 if (!wildcard
->enabled
)
1475 cds_list_for_each_entry(ev
, &wildcard
->events
, wildcard_list
) {
1476 ret
= ltt_event_disable(ev
);
1478 DBG("Error: disable error.\n");
1482 wildcard
->enabled
= 0;
1487 * Take the TLS "fault" in libuuid if dlopen'd, which can take the
1488 * dynamic linker mutex, outside of the UST lock, since the UST lock is
1489 * taken in constructors, which are called with dynamic linker mutex
1492 void lttng_fixup_event_tls(void)
1494 unsigned char uuid
[LTTNG_UST_UUID_STR_LEN
];
1496 (void) lttng_ust_uuid_generate(uuid
);