2 * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
4 * SPDX-License-Identifier: GPL-2.0-only
15 #include <sys/types.h>
17 #include <common/common.h>
18 #include <common/hashtable/utils.h>
19 #include <common/trace-chunk.h>
20 #include <common/kernel-ctl/kernel-ctl.h>
21 #include <common/kernel-ctl/kernel-ioctl.h>
22 #include <common/sessiond-comm/sessiond-comm.h>
24 #include <lttng/userspace-probe.h>
25 #include <lttng/userspace-probe-internal.h>
26 #include <lttng/condition/event-rule.h>
27 #include <lttng/condition/event-rule-internal.h>
28 #include <lttng/event-rule/event-rule.h>
29 #include <lttng/event-rule/event-rule-internal.h>
30 #include <lttng/event-rule/uprobe-internal.h>
32 #include "lttng-sessiond.h"
33 #include "lttng-syscall.h"
36 #include "kernel-consumer.h"
37 #include "kern-modules.h"
41 #include "notification-thread-commands.h"
44 * Key used to reference a channel between the sessiond and the consumer. This
45 * is only read and updated with the session_list lock held.
47 static uint64_t next_kernel_channel_key
;
49 static const char *module_proc_lttng
= "/proc/lttng";
51 static int kernel_tracer_fd
= -1;
52 static int kernel_tracer_trigger_group_fd
= -1;
53 static int kernel_tracer_trigger_group_notification_fd
= -1;
54 static struct ltt_kernel_token_event_rule_list kernel_tracer_token_list
;
57 * Add context on a kernel channel.
59 * Assumes the ownership of ctx.
61 int kernel_add_channel_context(struct ltt_kernel_channel
*chan
,
62 struct ltt_kernel_context
*ctx
)
69 DBG("Adding context to channel %s", chan
->channel
->name
);
70 ret
= kernctl_add_context(chan
->fd
, &ctx
->ctx
);
74 /* Exists but not available for this kernel */
75 ret
= LTTNG_ERR_KERN_CONTEXT_UNAVAILABLE
;
78 /* If EEXIST, we just ignore the error */
82 PERROR("add context ioctl");
83 ret
= LTTNG_ERR_KERN_CONTEXT_FAIL
;
90 cds_list_add_tail(&ctx
->list
, &chan
->ctx_list
);
95 trace_kernel_destroy_context(ctx
);
101 * Create a new kernel session, register it to the kernel tracer and add it to
102 * the session daemon session.
104 int kernel_create_session(struct ltt_session
*session
)
107 struct ltt_kernel_session
*lks
;
111 /* Allocate data structure */
112 lks
= trace_kernel_create_session();
118 /* Kernel tracer session creation */
119 ret
= kernctl_create_session(kernel_tracer_fd
);
121 PERROR("ioctl kernel create session");
126 /* Prevent fd duplication after execlp() */
127 ret
= fcntl(lks
->fd
, F_SETFD
, FD_CLOEXEC
);
129 PERROR("fcntl session fd");
132 lks
->id
= session
->id
;
133 lks
->consumer_fds_sent
= 0;
134 session
->kernel_session
= lks
;
136 DBG("Kernel session created (fd: %d)", lks
->fd
);
139 * This is necessary since the creation time is present in the session
140 * name when it is generated.
142 if (session
->has_auto_generated_name
) {
143 ret
= kernctl_session_set_name(lks
->fd
, DEFAULT_SESSION_NAME
);
145 ret
= kernctl_session_set_name(lks
->fd
, session
->name
);
148 WARN("Could not set kernel session name for session %" PRIu64
" name: %s",
149 session
->id
, session
->name
);
152 ret
= kernctl_session_set_creation_time(lks
->fd
, session
->creation_time
);
154 WARN("Could not set kernel session creation time for session %" PRIu64
" name: %s",
155 session
->id
, session
->name
);
162 trace_kernel_destroy_session(lks
);
163 trace_kernel_free_session(lks
);
169 * Create a kernel channel, register it to the kernel tracer and add it to the
172 int kernel_create_channel(struct ltt_kernel_session
*session
,
173 struct lttng_channel
*chan
)
176 struct ltt_kernel_channel
*lkc
;
181 /* Allocate kernel channel */
182 lkc
= trace_kernel_create_channel(chan
);
187 DBG3("Kernel create channel %s with attr: %d, %" PRIu64
", %" PRIu64
", %u, %u, %d, %d",
188 chan
->name
, lkc
->channel
->attr
.overwrite
,
189 lkc
->channel
->attr
.subbuf_size
, lkc
->channel
->attr
.num_subbuf
,
190 lkc
->channel
->attr
.switch_timer_interval
, lkc
->channel
->attr
.read_timer_interval
,
191 lkc
->channel
->attr
.live_timer_interval
, lkc
->channel
->attr
.output
);
193 /* Kernel tracer channel creation */
194 ret
= kernctl_create_channel(session
->fd
, &lkc
->channel
->attr
);
196 PERROR("ioctl kernel create channel");
200 /* Setup the channel fd */
202 /* Prevent fd duplication after execlp() */
203 ret
= fcntl(lkc
->fd
, F_SETFD
, FD_CLOEXEC
);
205 PERROR("fcntl session fd");
208 /* Add channel to session */
209 cds_list_add(&lkc
->list
, &session
->channel_list
.head
);
210 session
->channel_count
++;
211 lkc
->session
= session
;
212 lkc
->key
= ++next_kernel_channel_key
;
214 DBG("Kernel channel %s created (fd: %d, key: %" PRIu64
")",
215 lkc
->channel
->name
, lkc
->fd
, lkc
->key
);
228 * Create a kernel channel, register it to the kernel tracer and add it to the
232 int kernel_create_trigger_group(int *trigger_group_fd
)
237 assert(trigger_group_fd
);
239 /* Kernel tracer channel creation */
240 ret
= kernctl_create_trigger_group(kernel_tracer_fd
);
242 PERROR("ioctl kernel create trigger group");
250 /* Prevent fd duplication after execlp() */
251 ret
= fcntl(local_fd
, F_SETFD
, FD_CLOEXEC
);
253 PERROR("fcntl session fd");
256 DBG("Kernel trigger group created (fd: %d)",
261 *trigger_group_fd
= local_fd
;
266 * Compute the offset of the instrumentation byte in the binary based on the
267 * function probe location using the ELF lookup method.
269 * Returns 0 on success and set the offset out parameter to the offset of the
271 * Returns -1 on error
274 int extract_userspace_probe_offset_function_elf(
275 const struct lttng_userspace_probe_location
*probe_location
,
276 uid_t uid
, gid_t gid
, uint64_t *offset
)
280 const char *symbol
= NULL
;
281 const struct lttng_userspace_probe_location_lookup_method
*lookup
= NULL
;
282 enum lttng_userspace_probe_location_lookup_method_type lookup_method_type
;
284 assert(lttng_userspace_probe_location_get_type(probe_location
) ==
285 LTTNG_USERSPACE_PROBE_LOCATION_TYPE_FUNCTION
);
287 lookup
= lttng_userspace_probe_location_get_lookup_method(
295 lttng_userspace_probe_location_lookup_method_get_type(lookup
);
297 assert(lookup_method_type
==
298 LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF
);
300 symbol
= lttng_userspace_probe_location_function_get_function_name(
307 fd
= lttng_userspace_probe_location_function_get_binary_fd(probe_location
);
313 ret
= run_as_extract_elf_symbol_offset(fd
, symbol
, uid
, gid
, offset
);
315 DBG("userspace probe offset calculation failed for "
316 "function %s", symbol
);
320 DBG("userspace probe elf offset for %s is 0x%jd", symbol
, (intmax_t)(*offset
));
326 * Compute the offsets of the instrumentation bytes in the binary based on the
327 * tracepoint probe location using the SDT lookup method. This function
328 * allocates the offsets buffer, the caller must free it.
330 * Returns 0 on success and set the offset out parameter to the offsets of the
332 * Returns -1 on error.
335 int extract_userspace_probe_offset_tracepoint_sdt(
336 const struct lttng_userspace_probe_location
*probe_location
,
337 uid_t uid
, gid_t gid
, uint64_t **offsets
,
338 uint32_t *offsets_count
)
340 enum lttng_userspace_probe_location_lookup_method_type lookup_method_type
;
341 const struct lttng_userspace_probe_location_lookup_method
*lookup
= NULL
;
342 const char *probe_name
= NULL
, *provider_name
= NULL
;
346 assert(lttng_userspace_probe_location_get_type(probe_location
) ==
347 LTTNG_USERSPACE_PROBE_LOCATION_TYPE_TRACEPOINT
);
349 lookup
= lttng_userspace_probe_location_get_lookup_method(probe_location
);
356 lttng_userspace_probe_location_lookup_method_get_type(lookup
);
358 assert(lookup_method_type
==
359 LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT
);
362 probe_name
= lttng_userspace_probe_location_tracepoint_get_probe_name(
369 provider_name
= lttng_userspace_probe_location_tracepoint_get_provider_name(
371 if (!provider_name
) {
376 fd
= lttng_userspace_probe_location_tracepoint_get_binary_fd(probe_location
);
382 ret
= run_as_extract_sdt_probe_offsets(fd
, provider_name
, probe_name
,
383 uid
, gid
, offsets
, offsets_count
);
385 DBG("userspace probe offset calculation failed for sdt "
386 "probe %s:%s", provider_name
, probe_name
);
390 if (*offsets_count
== 0) {
391 DBG("no userspace probe offset found");
395 DBG("%u userspace probe SDT offsets found for %s:%s at:",
396 *offsets_count
, provider_name
, probe_name
);
397 for (i
= 0; i
< *offsets_count
; i
++) {
398 DBG("\t0x%jd", (intmax_t)((*offsets
)[i
]));
405 int userspace_probe_add_callsite(
406 const struct lttng_userspace_probe_location
*location
,
407 uid_t uid
, gid_t gid
, int fd
)
409 const struct lttng_userspace_probe_location_lookup_method
*lookup_method
= NULL
;
410 enum lttng_userspace_probe_location_lookup_method_type type
;
413 lookup_method
= lttng_userspace_probe_location_get_lookup_method(location
);
414 if (!lookup_method
) {
419 type
= lttng_userspace_probe_location_lookup_method_get_type(lookup_method
);
421 case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_FUNCTION_ELF
:
423 struct lttng_kernel_event_callsite callsite
;
426 ret
= extract_userspace_probe_offset_function_elf(location
,
429 ret
= LTTNG_ERR_PROBE_LOCATION_INVAL
;
433 callsite
.u
.uprobe
.offset
= offset
;
434 ret
= kernctl_add_callsite(fd
, &callsite
);
436 WARN("Adding callsite to ELF userspace probe failed.");
437 ret
= LTTNG_ERR_KERN_ENABLE_FAIL
;
442 case LTTNG_USERSPACE_PROBE_LOCATION_LOOKUP_METHOD_TYPE_TRACEPOINT_SDT
:
445 uint64_t *offsets
= NULL
;
446 uint32_t offsets_count
;
447 struct lttng_kernel_event_callsite callsite
;
450 * This call allocates the offsets buffer. This buffer must be freed
453 ret
= extract_userspace_probe_offset_tracepoint_sdt(location
,
454 uid
, gid
, &offsets
, &offsets_count
);
456 ret
= LTTNG_ERR_PROBE_LOCATION_INVAL
;
459 for (i
= 0; i
< offsets_count
; i
++) {
460 callsite
.u
.uprobe
.offset
= offsets
[i
];
461 ret
= kernctl_add_callsite(fd
, &callsite
);
463 WARN("Adding callsite to SDT userspace probe "
465 ret
= LTTNG_ERR_KERN_ENABLE_FAIL
;
474 ret
= LTTNG_ERR_PROBE_LOCATION_INVAL
;
482 * Extract the offsets of the instrumentation point for the different lookup
486 int userspace_probe_event_add_callsites(struct lttng_event
*ev
,
487 struct ltt_kernel_session
*session
, int fd
)
489 const struct lttng_userspace_probe_location
*location
= NULL
;
493 assert(ev
->type
== LTTNG_EVENT_USERSPACE_PROBE
);
495 location
= lttng_event_get_userspace_probe_location(ev
);
501 ret
= userspace_probe_add_callsite(location
, session
->uid
, session
->gid
,
504 WARN("Adding callsite to userspace probe event \"%s\" "
505 "failed.", ev
->name
);
513 * Extract the offsets of the instrumentation point for the different lookup
516 static int userspace_probe_event_rule_add_callsites(
517 const struct lttng_event_rule
*rule
,
518 const struct lttng_credentials
*creds
,
521 const struct lttng_userspace_probe_location
*location
= NULL
;
522 enum lttng_event_rule_status status
;
527 assert(lttng_event_rule_get_type(rule
) == LTTNG_EVENT_RULE_TYPE_UPROBE
);
529 status
= lttng_event_rule_uprobe_get_location(rule
, &location
);
530 if (status
!= LTTNG_EVENT_RULE_STATUS_OK
|| !location
) {
535 ret
= userspace_probe_add_callsite(location
, creds
->uid
, creds
->gid
,
538 WARN("Adding callsite to userspace probe object %d"
547 * Create a kernel event, enable it to the kernel tracer and add it to the
548 * channel event list of the kernel session.
549 * We own filter_expression and filter.
551 int kernel_create_event(struct lttng_event
*ev
,
552 struct ltt_kernel_channel
*channel
,
553 char *filter_expression
,
554 struct lttng_filter_bytecode
*filter
)
557 enum lttng_error_code ret
;
558 struct ltt_kernel_event
*event
;
563 /* We pass ownership of filter_expression and filter */
564 ret
= trace_kernel_create_event(ev
, filter_expression
,
566 if (ret
!= LTTNG_OK
) {
570 fd
= kernctl_create_event(channel
->fd
, event
->event
);
574 ret
= LTTNG_ERR_KERN_EVENT_EXIST
;
577 WARN("Event type not implemented");
578 ret
= LTTNG_ERR_KERN_EVENT_ENOSYS
;
581 WARN("Event %s not found!", ev
->name
);
582 ret
= LTTNG_ERR_KERN_ENABLE_FAIL
;
585 ret
= LTTNG_ERR_KERN_ENABLE_FAIL
;
586 PERROR("create event ioctl");
591 event
->type
= ev
->type
;
593 /* Prevent fd duplication after execlp() */
594 err
= fcntl(event
->fd
, F_SETFD
, FD_CLOEXEC
);
596 PERROR("fcntl session fd");
600 err
= kernctl_filter(event
->fd
, filter
);
604 ret
= LTTNG_ERR_FILTER_NOMEM
;
607 ret
= LTTNG_ERR_FILTER_INVAL
;
614 if (ev
->type
== LTTNG_EVENT_USERSPACE_PROBE
) {
615 ret
= userspace_probe_event_add_callsites(ev
, channel
->session
,
618 goto add_callsite_error
;
622 err
= kernctl_enable(event
->fd
);
626 ret
= LTTNG_ERR_KERN_EVENT_EXIST
;
629 PERROR("enable kernel event");
630 ret
= LTTNG_ERR_KERN_ENABLE_FAIL
;
636 /* Add event to event list */
637 cds_list_add(&event
->list
, &channel
->events_list
.head
);
638 channel
->event_count
++;
640 DBG("Event %s created (fd: %d)", ev
->name
, event
->fd
);
650 closeret
= close(event
->fd
);
652 PERROR("close event fd");
662 * Disable a kernel channel.
664 int kernel_disable_channel(struct ltt_kernel_channel
*chan
)
670 ret
= kernctl_disable(chan
->fd
);
672 PERROR("disable chan ioctl");
677 DBG("Kernel channel %s disabled (fd: %d, key: %" PRIu64
")",
678 chan
->channel
->name
, chan
->fd
, chan
->key
);
687 * Enable a kernel channel.
689 int kernel_enable_channel(struct ltt_kernel_channel
*chan
)
695 ret
= kernctl_enable(chan
->fd
);
696 if (ret
< 0 && ret
!= -EEXIST
) {
697 PERROR("Enable kernel chan");
702 DBG("Kernel channel %s enabled (fd: %d, key: %" PRIu64
")",
703 chan
->channel
->name
, chan
->fd
, chan
->key
);
712 * Enable a kernel event.
714 int kernel_enable_event(struct ltt_kernel_event
*event
)
720 ret
= kernctl_enable(event
->fd
);
724 ret
= LTTNG_ERR_KERN_EVENT_EXIST
;
727 PERROR("enable kernel event");
734 DBG("Kernel event %s enabled (fd: %d)", event
->event
->name
, event
->fd
);
743 * Disable a kernel event.
745 int kernel_disable_event(struct ltt_kernel_event
*event
)
751 ret
= kernctl_disable(event
->fd
);
755 ret
= LTTNG_ERR_KERN_EVENT_EXIST
;
758 PERROR("disable kernel event");
765 DBG("Kernel event %s disabled (fd: %d)", event
->event
->name
, event
->fd
);
774 * Disable a kernel trigger.
776 int kernel_disable_token_event_rule(struct ltt_kernel_token_event_rule
*event
)
782 ret
= kernctl_disable(event
->fd
);
786 ret
= LTTNG_ERR_KERN_EVENT_EXIST
;
789 PERROR("disable kernel event");
796 DBG("Kernel trigger token %" PRIu64
" disabled (fd: %d)", event
->token
, event
->fd
);
803 static struct lttng_tracker_list
*get_id_tracker_list(
804 struct ltt_kernel_session
*session
,
805 enum lttng_tracker_type tracker_type
)
807 switch (tracker_type
) {
808 case LTTNG_TRACKER_PID
:
809 return session
->tracker_list_pid
;
810 case LTTNG_TRACKER_VPID
:
811 return session
->tracker_list_vpid
;
812 case LTTNG_TRACKER_UID
:
813 return session
->tracker_list_uid
;
814 case LTTNG_TRACKER_VUID
:
815 return session
->tracker_list_vuid
;
816 case LTTNG_TRACKER_GID
:
817 return session
->tracker_list_gid
;
818 case LTTNG_TRACKER_VGID
:
819 return session
->tracker_list_vgid
;
825 int kernel_track_id(enum lttng_tracker_type tracker_type
,
826 struct ltt_kernel_session
*session
,
827 const struct lttng_tracker_id
*id
)
830 struct lttng_tracker_list
*tracker_list
;
831 struct lttng_tracker_ids
*saved_ids
;
833 ret
= lttng_tracker_id_lookup_string(tracker_type
, id
, &value
);
834 if (ret
!= LTTNG_OK
) {
838 tracker_list
= get_id_tracker_list(session
, tracker_type
);
840 return LTTNG_ERR_INVALID
;
843 /* Save list for restore on error. */
844 ret
= lttng_tracker_id_get_list(tracker_list
, &saved_ids
);
845 if (ret
!= LTTNG_OK
) {
846 return LTTNG_ERR_INVALID
;
850 ret
= lttng_tracker_list_add(tracker_list
, id
);
851 if (ret
!= LTTNG_OK
) {
855 switch (tracker_type
) {
856 case LTTNG_TRACKER_PID
:
857 DBG("Kernel track PID %d for session id %" PRIu64
".", value
,
859 ret
= kernctl_track_pid(session
->fd
, value
);
865 case LTTNG_TRACKER_VPID
:
866 DBG("Kernel track VPID %d for session id %" PRIu64
".", value
,
868 ret
= kernctl_track_id(session
->fd
, LTTNG_TRACKER_VPID
, value
);
874 case LTTNG_TRACKER_UID
:
875 DBG("Kernel track UID %d for session id %" PRIu64
".", value
,
877 ret
= kernctl_track_id(session
->fd
, LTTNG_TRACKER_UID
, value
);
883 case LTTNG_TRACKER_GID
:
884 DBG("Kernel track GID %d for session id %" PRIu64
".", value
,
886 ret
= kernctl_track_id(session
->fd
, LTTNG_TRACKER_GID
, value
);
892 case LTTNG_TRACKER_VUID
:
893 DBG("Kernel track VUID %d for session id %" PRIu64
".", value
,
895 ret
= kernctl_track_id(session
->fd
, LTTNG_TRACKER_VUID
, value
);
901 case LTTNG_TRACKER_VGID
:
902 DBG("Kernel track VGID %d for session id %" PRIu64
".", value
,
904 ret
= kernctl_track_id(session
->fd
, LTTNG_TRACKER_VGID
, value
);
915 /* Error handling. */
918 ret
= LTTNG_ERR_INVALID
;
921 ret
= LTTNG_ERR_NOMEM
;
924 ret
= LTTNG_ERR_ID_TRACKED
;
931 if (lttng_tracker_id_set_list(tracker_list
, saved_ids
) != LTTNG_OK
) {
932 ERR("Error on tracker add error handling.\n");
935 lttng_tracker_ids_destroy(saved_ids
);
939 int kernel_untrack_id(enum lttng_tracker_type tracker_type
,
940 struct ltt_kernel_session
*session
,
941 const struct lttng_tracker_id
*id
)
944 struct lttng_tracker_list
*tracker_list
;
945 struct lttng_tracker_ids
*saved_ids
;
947 ret
= lttng_tracker_id_lookup_string(tracker_type
, id
, &value
);
948 if (ret
!= LTTNG_OK
) {
952 tracker_list
= get_id_tracker_list(session
, tracker_type
);
954 return LTTNG_ERR_INVALID
;
956 /* Save list for restore on error. */
957 ret
= lttng_tracker_id_get_list(tracker_list
, &saved_ids
);
958 if (ret
!= LTTNG_OK
) {
959 return LTTNG_ERR_INVALID
;
961 /* Remove from list. */
962 ret
= lttng_tracker_list_remove(tracker_list
, id
);
963 if (ret
!= LTTNG_OK
) {
967 switch (tracker_type
) {
968 case LTTNG_TRACKER_PID
:
969 DBG("Kernel untrack PID %d for session id %" PRIu64
".", value
,
971 ret
= kernctl_untrack_pid(session
->fd
, value
);
977 case LTTNG_TRACKER_VPID
:
978 DBG("Kernel untrack VPID %d for session id %" PRIu64
".", value
,
980 ret
= kernctl_untrack_id(
981 session
->fd
, LTTNG_TRACKER_VPID
, value
);
987 case LTTNG_TRACKER_UID
:
988 DBG("Kernel untrack UID %d for session id %" PRIu64
".", value
,
990 ret
= kernctl_untrack_id(session
->fd
, LTTNG_TRACKER_UID
, value
);
996 case LTTNG_TRACKER_GID
:
997 DBG("Kernel untrack GID %d for session id %" PRIu64
".", value
,
999 ret
= kernctl_untrack_id(session
->fd
, LTTNG_TRACKER_GID
, value
);
1005 case LTTNG_TRACKER_VUID
:
1006 DBG("Kernel untrack VUID %d for session id %" PRIu64
".", value
,
1008 ret
= kernctl_untrack_id(
1009 session
->fd
, LTTNG_TRACKER_VUID
, value
);
1015 case LTTNG_TRACKER_VGID
:
1016 DBG("Kernel untrack VGID %d for session id %" PRIu64
".", value
,
1018 ret
= kernctl_untrack_id(
1019 session
->fd
, LTTNG_TRACKER_VGID
, value
);
1030 /* Error handling. */
1033 ret
= LTTNG_ERR_INVALID
;
1036 ret
= LTTNG_ERR_NOMEM
;
1039 ret
= LTTNG_ERR_ID_TRACKED
;
1042 ret
= LTTNG_ERR_UNK
;
1046 if (lttng_tracker_id_set_list(tracker_list
, saved_ids
) != LTTNG_OK
) {
1047 ERR("Error on tracker remove error handling.\n");
1050 lttng_tracker_ids_destroy(saved_ids
);
1055 * Called with session lock held.
1057 int kernel_list_tracker_ids(enum lttng_tracker_type tracker_type
,
1058 struct ltt_kernel_session
*session
,
1059 struct lttng_tracker_ids
**_ids
)
1062 struct lttng_tracker_list
*tracker_list
;
1064 tracker_list
= get_id_tracker_list(session
, tracker_type
);
1065 if (!tracker_list
) {
1066 ret
= -LTTNG_ERR_INVALID
;
1070 ret
= lttng_tracker_id_get_list(tracker_list
, _ids
);
1071 if (ret
!= LTTNG_OK
) {
1072 ret
= -LTTNG_ERR_INVALID
;
1081 * Create kernel metadata, open from the kernel tracer and add it to the
1084 int kernel_open_metadata(struct ltt_kernel_session
*session
)
1087 struct ltt_kernel_metadata
*lkm
= NULL
;
1091 /* Allocate kernel metadata */
1092 lkm
= trace_kernel_create_metadata();
1097 /* Kernel tracer metadata creation */
1098 ret
= kernctl_open_metadata(session
->fd
, &lkm
->conf
->attr
);
1104 lkm
->key
= ++next_kernel_channel_key
;
1105 /* Prevent fd duplication after execlp() */
1106 ret
= fcntl(lkm
->fd
, F_SETFD
, FD_CLOEXEC
);
1108 PERROR("fcntl session fd");
1111 session
->metadata
= lkm
;
1113 DBG("Kernel metadata opened (fd: %d)", lkm
->fd
);
1118 trace_kernel_destroy_metadata(lkm
);
1124 * Start tracing session.
1126 int kernel_start_session(struct ltt_kernel_session
*session
)
1132 ret
= kernctl_start_session(session
->fd
);
1134 PERROR("ioctl start session");
1138 DBG("Kernel session started");
1147 * Make a kernel wait to make sure in-flight probe have completed.
1149 void kernel_wait_quiescent(void)
1152 int fd
= kernel_tracer_fd
;
1154 DBG("Kernel quiescent wait on %d", fd
);
1156 ret
= kernctl_wait_quiescent(fd
);
1158 PERROR("wait quiescent ioctl");
1159 ERR("Kernel quiescent wait failed");
1164 * Force flush buffer of metadata.
1166 int kernel_metadata_flush_buffer(int fd
)
1170 DBG("Kernel flushing metadata buffer on fd %d", fd
);
1172 ret
= kernctl_buffer_flush(fd
);
1174 ERR("Fail to flush metadata buffers %d (ret: %d)", fd
, ret
);
1181 * Force flush buffer for channel.
1183 int kernel_flush_buffer(struct ltt_kernel_channel
*channel
)
1186 struct ltt_kernel_stream
*stream
;
1190 DBG("Flush buffer for channel %s", channel
->channel
->name
);
1192 cds_list_for_each_entry(stream
, &channel
->stream_list
.head
, list
) {
1193 DBG("Flushing channel stream %d", stream
->fd
);
1194 ret
= kernctl_buffer_flush(stream
->fd
);
1197 ERR("Fail to flush buffer for stream %d (ret: %d)",
1206 * Stop tracing session.
1208 int kernel_stop_session(struct ltt_kernel_session
*session
)
1214 ret
= kernctl_stop_session(session
->fd
);
1219 DBG("Kernel session stopped");
1228 * Open stream of channel, register it to the kernel tracer and add it
1229 * to the stream list of the channel.
1231 * Note: given that the streams may appear in random order wrt CPU
1232 * number (e.g. cpu hotplug), the index value of the stream number in
1233 * the stream name is not necessarily linked to the CPU number.
1235 * Return the number of created stream. Else, a negative value.
1237 int kernel_open_channel_stream(struct ltt_kernel_channel
*channel
)
1240 struct ltt_kernel_stream
*lks
;
1244 while ((ret
= kernctl_create_stream(channel
->fd
)) >= 0) {
1245 lks
= trace_kernel_create_stream(channel
->channel
->name
,
1246 channel
->stream_count
);
1256 /* Prevent fd duplication after execlp() */
1257 ret
= fcntl(lks
->fd
, F_SETFD
, FD_CLOEXEC
);
1259 PERROR("fcntl session fd");
1262 lks
->tracefile_size
= channel
->channel
->attr
.tracefile_size
;
1263 lks
->tracefile_count
= channel
->channel
->attr
.tracefile_count
;
1265 /* Add stream to channel stream list */
1266 cds_list_add(&lks
->list
, &channel
->stream_list
.head
);
1267 channel
->stream_count
++;
1269 DBG("Kernel stream %s created (fd: %d, state: %d)", lks
->name
, lks
->fd
,
1273 return channel
->stream_count
;
1280 * Open the metadata stream and set it to the kernel session.
1282 int kernel_open_metadata_stream(struct ltt_kernel_session
*session
)
1288 ret
= kernctl_create_stream(session
->metadata
->fd
);
1290 PERROR("kernel create metadata stream");
1294 DBG("Kernel metadata stream created (fd: %d)", ret
);
1295 session
->metadata_stream_fd
= ret
;
1296 /* Prevent fd duplication after execlp() */
1297 ret
= fcntl(session
->metadata_stream_fd
, F_SETFD
, FD_CLOEXEC
);
1299 PERROR("fcntl session fd");
1309 * Get the event list from the kernel tracer and return the number of elements.
1311 ssize_t
kernel_list_events(struct lttng_event
**events
)
1315 size_t nbmem
, count
= 0;
1317 struct lttng_event
*elist
;
1321 fd
= kernctl_tracepoint_list(kernel_tracer_fd
);
1323 PERROR("kernel tracepoint list");
1327 fp
= fdopen(fd
, "r");
1329 PERROR("kernel tracepoint list fdopen");
1334 * Init memory size counter
1335 * See kernel-ctl.h for explanation of this value
1337 nbmem
= KERNEL_EVENT_INIT_LIST_SIZE
;
1338 elist
= zmalloc(sizeof(struct lttng_event
) * nbmem
);
1339 if (elist
== NULL
) {
1340 PERROR("alloc list events");
1345 while (fscanf(fp
, "event { name = %m[^;]; };\n", &event
) == 1) {
1346 if (count
>= nbmem
) {
1347 struct lttng_event
*new_elist
;
1350 new_nbmem
= nbmem
<< 1;
1351 DBG("Reallocating event list from %zu to %zu bytes",
1353 new_elist
= realloc(elist
, new_nbmem
* sizeof(struct lttng_event
));
1354 if (new_elist
== NULL
) {
1355 PERROR("realloc list events");
1361 /* Zero the new memory */
1362 memset(new_elist
+ nbmem
, 0,
1363 (new_nbmem
- nbmem
) * sizeof(struct lttng_event
));
1367 strncpy(elist
[count
].name
, event
, LTTNG_SYMBOL_NAME_LEN
);
1368 elist
[count
].name
[LTTNG_SYMBOL_NAME_LEN
- 1] = '\0';
1369 elist
[count
].enabled
= -1;
1375 DBG("Kernel list events done (%zu events)", count
);
1377 ret
= fclose(fp
); /* closes both fp and fd */
1393 * Get kernel version and validate it.
1395 int kernel_validate_version(struct lttng_kernel_tracer_version
*version
,
1396 struct lttng_kernel_tracer_abi_version
*abi_version
)
1400 ret
= kernctl_tracer_version(kernel_tracer_fd
, version
);
1402 ERR("Failed to retrieve the lttng-modules version");
1406 /* Validate version */
1407 if (version
->major
!= VERSION_MAJOR
) {
1408 ERR("Kernel tracer major version (%d) is not compatible with lttng-tools major version (%d)",
1409 version
->major
, VERSION_MAJOR
);
1412 ret
= kernctl_tracer_abi_version(kernel_tracer_fd
, abi_version
);
1414 ERR("Failed to retrieve lttng-modules ABI version");
1417 if (abi_version
->major
!= LTTNG_MODULES_ABI_MAJOR_VERSION
) {
1418 ERR("Kernel tracer ABI version (%d.%d) does not match the expected ABI major version (%d.*)",
1419 abi_version
->major
, abi_version
->minor
,
1420 LTTNG_MODULES_ABI_MAJOR_VERSION
);
1423 DBG2("Kernel tracer version validated (%d.%d, ABI %d.%d)",
1424 version
->major
, version
->minor
,
1425 abi_version
->major
, abi_version
->minor
);
1432 ERR("Kernel tracer version check failed; kernel tracing will not be available");
1437 * Kernel work-arounds called at the start of sessiond main().
1439 int init_kernel_workarounds(void)
1445 * boot_id needs to be read once before being used concurrently
1446 * to deal with a Linux kernel race. A fix is proposed for
1447 * upstream, but the work-around is needed for older kernels.
1449 fp
= fopen("/proc/sys/kernel/random/boot_id", "r");
1456 ret
= fread(buf
, 1, sizeof(buf
), fp
);
1458 /* Ignore error, we don't really care */
1470 * Teardown of a kernel session, keeping data required by destroy notifiers.
1472 void kernel_destroy_session(struct ltt_kernel_session
*ksess
)
1474 struct lttng_trace_chunk
*trace_chunk
;
1476 if (ksess
== NULL
) {
1477 DBG3("No kernel session when tearing down session");
1481 DBG("Tearing down kernel session");
1482 trace_chunk
= ksess
->current_trace_chunk
;
1485 * Destroy channels on the consumer if at least one FD has been sent and we
1486 * are in no output mode because the streams are in *no* monitor mode so we
1487 * have to send a command to clean them up or else they leaked.
1489 if (!ksess
->output_traces
&& ksess
->consumer_fds_sent
) {
1491 struct consumer_socket
*socket
;
1492 struct lttng_ht_iter iter
;
1494 /* For each consumer socket. */
1496 cds_lfht_for_each_entry(ksess
->consumer
->socks
->ht
, &iter
.iter
,
1497 socket
, node
.node
) {
1498 struct ltt_kernel_channel
*chan
;
1500 /* For each channel, ask the consumer to destroy it. */
1501 cds_list_for_each_entry(chan
, &ksess
->channel_list
.head
, list
) {
1502 ret
= kernel_consumer_destroy_channel(socket
, chan
);
1504 /* Consumer is probably dead. Use next socket. */
1512 /* Close any relayd session */
1513 consumer_output_send_destroy_relayd(ksess
->consumer
);
1515 trace_kernel_destroy_session(ksess
);
1516 lttng_trace_chunk_put(trace_chunk
);
1519 /* Teardown of data required by destroy notifiers. */
1520 void kernel_free_session(struct ltt_kernel_session
*ksess
)
1522 if (ksess
== NULL
) {
1525 trace_kernel_free_session(ksess
);
1529 * Destroy a kernel channel object. It does not do anything on the tracer side.
1531 void kernel_destroy_channel(struct ltt_kernel_channel
*kchan
)
1533 struct ltt_kernel_session
*ksess
= NULL
;
1536 assert(kchan
->channel
);
1538 DBG3("Kernel destroy channel %s", kchan
->channel
->name
);
1540 /* Update channel count of associated session. */
1541 if (kchan
->session
) {
1542 /* Keep pointer reference so we can update it after the destroy. */
1543 ksess
= kchan
->session
;
1546 trace_kernel_destroy_channel(kchan
);
1549 * At this point the kernel channel is not visible anymore. This is safe
1550 * since in order to work on a visible kernel session, the tracing session
1551 * lock (ltt_session.lock) MUST be acquired.
1554 ksess
->channel_count
--;
1559 * Take a snapshot for a given kernel session.
1561 * Return LTTNG_OK on success or else return a LTTNG_ERR code.
1563 enum lttng_error_code
kernel_snapshot_record(
1564 struct ltt_kernel_session
*ksess
,
1565 const struct consumer_output
*output
, int wait
,
1566 uint64_t nb_packets_per_stream
)
1568 int err
, ret
, saved_metadata_fd
;
1569 enum lttng_error_code status
= LTTNG_OK
;
1570 struct consumer_socket
*socket
;
1571 struct lttng_ht_iter iter
;
1572 struct ltt_kernel_metadata
*saved_metadata
;
1573 char *trace_path
= NULL
;
1574 size_t consumer_path_offset
= 0;
1577 assert(ksess
->consumer
);
1580 DBG("Kernel snapshot record started");
1582 /* Save current metadata since the following calls will change it. */
1583 saved_metadata
= ksess
->metadata
;
1584 saved_metadata_fd
= ksess
->metadata_stream_fd
;
1588 ret
= kernel_open_metadata(ksess
);
1590 status
= LTTNG_ERR_KERN_META_FAIL
;
1594 ret
= kernel_open_metadata_stream(ksess
);
1596 status
= LTTNG_ERR_KERN_META_FAIL
;
1597 goto error_open_stream
;
1600 trace_path
= setup_channel_trace_path(ksess
->consumer
,
1601 DEFAULT_KERNEL_TRACE_DIR
, &consumer_path_offset
);
1603 status
= LTTNG_ERR_INVALID
;
1606 /* Send metadata to consumer and snapshot everything. */
1607 cds_lfht_for_each_entry(output
->socks
->ht
, &iter
.iter
,
1608 socket
, node
.node
) {
1609 struct ltt_kernel_channel
*chan
;
1611 pthread_mutex_lock(socket
->lock
);
1612 /* This stream must not be monitored by the consumer. */
1613 ret
= kernel_consumer_add_metadata(socket
, ksess
, 0);
1614 pthread_mutex_unlock(socket
->lock
);
1616 status
= LTTNG_ERR_KERN_META_FAIL
;
1617 goto error_consumer
;
1620 /* For each channel, ask the consumer to snapshot it. */
1621 cds_list_for_each_entry(chan
, &ksess
->channel_list
.head
, list
) {
1622 status
= consumer_snapshot_channel(socket
, chan
->key
, output
, 0,
1623 ksess
->uid
, ksess
->gid
,
1624 &trace_path
[consumer_path_offset
], wait
,
1625 nb_packets_per_stream
);
1626 if (status
!= LTTNG_OK
) {
1627 (void) kernel_consumer_destroy_metadata(socket
,
1629 goto error_consumer
;
1633 /* Snapshot metadata, */
1634 status
= consumer_snapshot_channel(socket
, ksess
->metadata
->key
, output
,
1635 1, ksess
->uid
, ksess
->gid
, &trace_path
[consumer_path_offset
],
1637 if (status
!= LTTNG_OK
) {
1638 goto error_consumer
;
1642 * The metadata snapshot is done, ask the consumer to destroy it since
1643 * it's not monitored on the consumer side.
1645 (void) kernel_consumer_destroy_metadata(socket
, ksess
->metadata
);
1649 /* Close newly opened metadata stream. It's now on the consumer side. */
1650 err
= close(ksess
->metadata_stream_fd
);
1652 PERROR("close snapshot kernel");
1656 trace_kernel_destroy_metadata(ksess
->metadata
);
1658 /* Restore metadata state.*/
1659 ksess
->metadata
= saved_metadata
;
1660 ksess
->metadata_stream_fd
= saved_metadata_fd
;
1667 * Get the syscall mask array from the kernel tracer.
1669 * Return 0 on success else a negative value. In both case, syscall_mask should
1672 int kernel_syscall_mask(int chan_fd
, char **syscall_mask
, uint32_t *nr_bits
)
1674 assert(syscall_mask
);
1677 return kernctl_syscall_mask(chan_fd
, syscall_mask
, nr_bits
);
1681 * Check for the support of the RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS via abi
1684 * Return 1 on success, 0 when feature is not supported, negative value in case
1687 int kernel_supports_ring_buffer_snapshot_sample_positions(void)
1689 int ret
= 0; // Not supported by default
1690 struct lttng_kernel_tracer_abi_version abi
;
1692 ret
= kernctl_tracer_abi_version(kernel_tracer_fd
, &abi
);
1694 ERR("Failed to retrieve lttng-modules ABI version");
1699 * RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS was introduced in 2.3
1701 if (abi
.major
>= 2 && abi
.minor
>= 3) {
1713 * Check for the support of the packet sequence number via abi version number.
1715 * Return 1 on success, 0 when feature is not supported, negative value in case
1718 int kernel_supports_ring_buffer_packet_sequence_number(void)
1720 int ret
= 0; // Not supported by default
1721 struct lttng_kernel_tracer_abi_version abi
;
1723 ret
= kernctl_tracer_abi_version(kernel_tracer_fd
, &abi
);
1725 ERR("Failed to retrieve lttng-modules ABI version");
1730 * Packet sequence number was introduced in LTTng 2.8,
1731 * lttng-modules ABI 2.1.
1733 if (abi
.major
>= 2 && abi
.minor
>= 1) {
1745 * Rotate a kernel session.
1747 * Return LTTNG_OK on success or else an LTTng error code.
1749 enum lttng_error_code
kernel_rotate_session(struct ltt_session
*session
)
1752 enum lttng_error_code status
= LTTNG_OK
;
1753 struct consumer_socket
*socket
;
1754 struct lttng_ht_iter iter
;
1755 struct ltt_kernel_session
*ksess
= session
->kernel_session
;
1758 assert(ksess
->consumer
);
1760 DBG("Rotate kernel session %s started (session %" PRIu64
")",
1761 session
->name
, session
->id
);
1766 * Note that this loop will end after one iteration given that there is
1767 * only one kernel consumer.
1769 cds_lfht_for_each_entry(ksess
->consumer
->socks
->ht
, &iter
.iter
,
1770 socket
, node
.node
) {
1771 struct ltt_kernel_channel
*chan
;
1773 /* For each channel, ask the consumer to rotate it. */
1774 cds_list_for_each_entry(chan
, &ksess
->channel_list
.head
, list
) {
1775 DBG("Rotate kernel channel %" PRIu64
", session %s",
1776 chan
->key
, session
->name
);
1777 ret
= consumer_rotate_channel(socket
, chan
->key
,
1778 ksess
->uid
, ksess
->gid
, ksess
->consumer
,
1779 /* is_metadata_channel */ false);
1781 status
= LTTNG_ERR_KERN_CONSUMER_FAIL
;
1787 * Rotate the metadata channel.
1789 ret
= consumer_rotate_channel(socket
, ksess
->metadata
->key
,
1790 ksess
->uid
, ksess
->gid
, ksess
->consumer
,
1791 /* is_metadata_channel */ true);
1793 status
= LTTNG_ERR_KERN_CONSUMER_FAIL
;
1803 enum lttng_error_code
kernel_create_channel_subdirectories(
1804 const struct ltt_kernel_session
*ksess
)
1806 enum lttng_error_code ret
= LTTNG_OK
;
1807 enum lttng_trace_chunk_status chunk_status
;
1810 assert(ksess
->current_trace_chunk
);
1813 * Create the index subdirectory which will take care
1814 * of implicitly creating the channel's path.
1816 chunk_status
= lttng_trace_chunk_create_subdirectory(
1817 ksess
->current_trace_chunk
,
1818 DEFAULT_KERNEL_TRACE_DIR
"/" DEFAULT_INDEX_DIR
);
1819 if (chunk_status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
1820 ret
= LTTNG_ERR_CREATE_DIR_FAIL
;
1829 * Setup necessary data for kernel tracer action.
1832 int init_kernel_tracer(void)
1835 bool is_root
= !getuid();
1837 /* Modprobe lttng kernel modules */
1838 ret
= modprobe_lttng_control();
1843 /* Open debugfs lttng */
1844 kernel_tracer_fd
= open(module_proc_lttng
, O_RDWR
);
1845 if (kernel_tracer_fd
< 0) {
1846 DBG("Failed to open %s", module_proc_lttng
);
1850 /* Validate kernel version */
1851 ret
= kernel_validate_version(&kernel_tracer_version
,
1852 &kernel_tracer_abi_version
);
1857 ret
= modprobe_lttng_data();
1862 ret
= kernel_supports_ring_buffer_snapshot_sample_positions();
1867 WARN("Kernel tracer does not support buffer monitoring. "
1868 "The monitoring timer of channels in the kernel domain "
1869 "will be set to 0 (disabled).");
1872 ret
= kernel_create_trigger_group(&kernel_tracer_trigger_group_fd
);
1874 /* TODO: error handling if it is not supported etc. */
1875 WARN("Failed trigger group creation");
1876 kernel_tracer_trigger_group_fd
= -1;
1877 /* This is not fatal */
1879 ret
= kernel_create_trigger_group_notification_fd(&kernel_tracer_trigger_group_notification_fd
);
1885 CDS_INIT_LIST_HEAD(&kernel_tracer_token_list
.head
);
1887 DBG("Kernel tracer fd %d", kernel_tracer_fd
);
1888 DBG("Kernel tracer trigger group fd %d", kernel_tracer_trigger_group_fd
);
1889 DBG("Kernel tracer trigger group notificationi fd %d", kernel_tracer_trigger_group_notification_fd
);
1891 ret
= syscall_init_table(kernel_tracer_fd
);
1893 ERR("Unable to populate syscall table. Syscall tracing won't "
1894 "work for this session daemon.");
1900 modprobe_remove_lttng_control();
1901 ret
= close(kernel_tracer_fd
);
1905 kernel_tracer_fd
= -1;
1906 return LTTNG_ERR_KERN_VERSION
;
1909 ret
= close(kernel_tracer_fd
);
1915 modprobe_remove_lttng_control();
1918 WARN("No kernel tracer available");
1919 kernel_tracer_fd
= -1;
1921 return LTTNG_ERR_NEED_ROOT_SESSIOND
;
1923 return LTTNG_ERR_KERN_NA
;
1928 void cleanup_kernel_tracer(void)
1932 struct ltt_kernel_token_event_rule
*rule
, *rtmp
;
1933 cds_list_for_each_entry_safe(rule
, rtmp
, &kernel_tracer_token_list
.head
, list
) {
1934 kernel_disable_token_event_rule(rule
);
1935 trace_kernel_destroy_token_event_rule(rule
);
1938 DBG2("Closing kernel trigger group notification fd");
1939 if (kernel_tracer_trigger_group_notification_fd
>= 0) {
1940 ret
= close(kernel_tracer_trigger_group_notification_fd
);
1944 kernel_tracer_trigger_group_notification_fd
= -1;
1947 /* TODO: do we iterate over the list to remove all token? */
1948 DBG2("Closing kernel trigger group fd");
1949 if (kernel_tracer_trigger_group_fd
>= 0) {
1950 ret
= close(kernel_tracer_trigger_group_fd
);
1954 kernel_tracer_trigger_group_fd
= -1;
1957 DBG2("Closing kernel fd");
1958 if (kernel_tracer_fd
>= 0) {
1959 ret
= close(kernel_tracer_fd
);
1963 kernel_tracer_fd
= -1;
1967 DBG("Unloading kernel modules");
1968 modprobe_remove_lttng_all();
1969 free(syscall_table
);
1973 bool kernel_tracer_is_initialized(void)
1975 return kernel_tracer_fd
>= 0;
1979 * Clear a kernel session.
1981 * Return LTTNG_OK on success or else an LTTng error code.
1983 enum lttng_error_code
kernel_clear_session(struct ltt_session
*session
)
1986 enum lttng_error_code status
= LTTNG_OK
;
1987 struct consumer_socket
*socket
;
1988 struct lttng_ht_iter iter
;
1989 struct ltt_kernel_session
*ksess
= session
->kernel_session
;
1992 assert(ksess
->consumer
);
1994 DBG("Clear kernel session %s (session %" PRIu64
")",
1995 session
->name
, session
->id
);
1999 if (ksess
->active
) {
2000 ERR("Expecting inactive session %s (%" PRIu64
")", session
->name
, session
->id
);
2001 status
= LTTNG_ERR_FATAL
;
2006 * Note that this loop will end after one iteration given that there is
2007 * only one kernel consumer.
2009 cds_lfht_for_each_entry(ksess
->consumer
->socks
->ht
, &iter
.iter
,
2010 socket
, node
.node
) {
2011 struct ltt_kernel_channel
*chan
;
2013 /* For each channel, ask the consumer to clear it. */
2014 cds_list_for_each_entry(chan
, &ksess
->channel_list
.head
, list
) {
2015 DBG("Clear kernel channel %" PRIu64
", session %s",
2016 chan
->key
, session
->name
);
2017 ret
= consumer_clear_channel(socket
, chan
->key
);
2023 if (!ksess
->metadata
) {
2025 * Nothing to do for the metadata.
2026 * This is a snapshot session.
2027 * The metadata is genererated on the fly.
2033 * Clear the metadata channel.
2034 * Metadata channel is not cleared per se but we still need to
2035 * perform a rotation operation on it behind the scene.
2037 ret
= consumer_clear_channel(socket
, ksess
->metadata
->key
);
2046 case LTTCOMM_CONSUMERD_RELAYD_CLEAR_DISALLOWED
:
2047 status
= LTTNG_ERR_CLEAR_RELAY_DISALLOWED
;
2050 status
= LTTNG_ERR_CLEAR_FAIL_CONSUMER
;
2058 enum lttng_error_code
kernel_create_trigger_group_notification_fd(
2059 int *trigger_group_notification_fd
)
2061 enum lttng_error_code ret
= LTTNG_OK
;
2064 assert(trigger_group_notification_fd
);
2066 ret
= kernctl_create_trigger_group_notification_fd(kernel_tracer_trigger_group_fd
);
2068 PERROR("ioctl kernel create trigger group");
2076 /* Prevent fd duplication after execlp() */
2077 ret
= fcntl(local_fd
, F_SETFD
, FD_CLOEXEC
);
2079 PERROR("fcntl session fd");
2082 DBG("Kernel trigger group notification created (fd: %d)",
2087 *trigger_group_notification_fd
= local_fd
;
2091 enum lttng_error_code
kernel_destroy_trigger_group_notification_fd(
2092 int trigger_group_notification_fd
)
2094 enum lttng_error_code ret
= LTTNG_OK
;
2095 DBG("Closing trigger group notification fd %d", trigger_group_notification_fd
);
2096 if (trigger_group_notification_fd
>= 0) {
2097 ret
= close(trigger_group_notification_fd
);
2105 static int kernel_create_token_event_rule(struct lttng_event_rule
*rule
,
2106 const struct lttng_credentials
*creds
, uint64_t token
)
2109 enum lttng_error_code ret
;
2110 struct ltt_kernel_token_event_rule
*event
;
2111 struct lttng_kernel_trigger trigger
;
2115 ret
= trace_kernel_create_token_event_rule(rule
, token
, &event
);
2116 if (ret
!= LTTNG_OK
) {
2120 trace_kernel_init_trigger_from_event_rule(event
->event_rule
, &trigger
);
2121 trigger
.id
= event
->token
;
2123 fd
= kernctl_create_trigger(kernel_tracer_trigger_group_fd
, &trigger
);
2127 ret
= LTTNG_ERR_KERN_EVENT_EXIST
;
2130 WARN("Trigger type not implemented");
2131 ret
= LTTNG_ERR_KERN_EVENT_ENOSYS
;
2134 WARN("Event %s not found!", trigger
.name
);
2135 ret
= LTTNG_ERR_KERN_ENABLE_FAIL
;
2138 ret
= LTTNG_ERR_KERN_ENABLE_FAIL
;
2139 PERROR("create trigger ioctl");
2145 /* Prevent fd duplication after execlp() */
2146 err
= fcntl(event
->fd
, F_SETFD
, FD_CLOEXEC
);
2148 PERROR("fcntl session fd");
2151 if (event
->filter
) {
2152 err
= kernctl_filter(event
->fd
, event
->filter
);
2156 ret
= LTTNG_ERR_FILTER_NOMEM
;
2159 ret
= LTTNG_ERR_FILTER_INVAL
;
2166 if (lttng_event_rule_get_type(event
->event_rule
) ==
2167 LTTNG_EVENT_RULE_TYPE_UPROBE
) {
2168 ret
= userspace_probe_event_rule_add_callsites(
2169 rule
, creds
, event
->fd
);
2171 goto add_callsite_error
;
2175 err
= kernctl_enable(event
->fd
);
2179 ret
= LTTNG_ERR_KERN_EVENT_EXIST
;
2182 PERROR("enable kernel trigger");
2183 ret
= LTTNG_ERR_KERN_ENABLE_FAIL
;
2189 /* Add event to event list */
2190 cds_list_add(&event
->list
, &kernel_tracer_token_list
.head
);
2192 DBG("Trigger %s created (fd: %d)", trigger
.name
, event
->fd
);
2202 closeret
= close(event
->fd
);
2204 PERROR("close event fd");
2213 enum lttng_error_code
kernel_update_tokens(void)
2215 enum lttng_error_code ret
= LTTNG_OK
;
2216 enum lttng_trigger_status t_status
;
2217 struct ltt_kernel_token_event_rule
*token_event_rule_element
;
2218 struct lttng_triggers
*triggers
;
2221 /* TODO error handling */
2223 /* Get list of token trigger from the notification thread here */
2225 pthread_mutex_lock(¬ification_trigger_tokens_ht_lock
);
2226 ret
= notification_thread_command_get_tokens(notification_thread_handle
, &triggers
);
2227 if (ret
!= LTTNG_OK
) {
2234 t_status
= lttng_triggers_get_count(triggers
, &count
);
2235 if (t_status
!= LTTNG_TRIGGER_STATUS_OK
) {
2240 for (unsigned int i
= 0; i
< count
; i
++) {
2241 struct lttng_condition
*condition
;
2242 struct lttng_event_rule
*event_rule
;
2243 struct lttng_trigger
*trigger
;
2244 struct ltt_kernel_token_event_rule
*k_token
;
2245 const struct lttng_credentials
*creds
;
2248 trigger
= lttng_triggers_get_pointer_of_index(triggers
, i
);
2251 /* TODO: error checking and type checking */
2252 token
= lttng_trigger_get_key(trigger
);
2253 condition
= lttng_trigger_get_condition(trigger
);
2254 (void) lttng_condition_event_rule_get_rule_no_const(condition
, &event_rule
);
2256 if (lttng_event_rule_get_domain_type(event_rule
) != LTTNG_DOMAIN_KERNEL
) {
2257 /* Skip ust related trigger */
2261 creds
= lttng_trigger_get_credentials(trigger
);
2262 /* Iterate over all known token trigger */
2263 k_token
= trace_kernel_find_trigger_by_token(&kernel_tracer_token_list
, token
);
2265 ret
= kernel_create_token_event_rule(event_rule
, creds
, token
);
2272 /* Remove all unknown trigger from the app
2273 * TODO find a way better way then this, do it on the unregister command
2274 * and be specific on the token to remove instead of going over all
2275 * trigger known to the app. This is sub optimal.
2277 cds_list_for_each_entry (token_event_rule_element
, &kernel_tracer_token_list
.head
,
2282 token
= token_event_rule_element
->token
;
2285 * Check if the app event trigger still exists on the
2286 * notification side.
2287 * TODO: might want to change the backing data struct of the
2288 * lttng_triggers object to allow quick lookup?
2289 * For kernel mostly all of this can be removed once we delete
2290 * on a per trigger basis.
2293 for (unsigned int i
= 0; i
< count
; i
++) {
2294 struct lttng_trigger
*trigger
;
2295 uint64_t inner_token
;
2297 trigger
= lttng_triggers_get_pointer_of_index(
2301 inner_token
= lttng_trigger_get_key(trigger
);
2303 if (inner_token
== token
) {
2314 kernel_disable_token_event_rule(token_event_rule_element
);
2315 trace_kernel_destroy_token_event_rule(token_event_rule_element
);
2319 pthread_mutex_unlock(¬ification_trigger_tokens_ht_lock
);
2324 int kernel_get_notification_fd(void)
2326 return kernel_tracer_trigger_group_notification_fd
;