1 /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
5 * Holds LTTng per-session event registry.
7 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
10 #ifndef _LTTNG_EVENTS_H
11 #define _LTTNG_EVENTS_H
13 #include <lttng/kernel-version.h>
14 #include <linux/list.h>
15 #include <linux/kprobes.h>
16 #include <linux/kref.h>
17 #include <linux/uuid.h>
18 #include <linux/irq_work.h>
19 #include <wrapper/uprobes.h>
20 #include <lttng/cpuhotplug.h>
21 #include <lttng/tracer.h>
22 #include <lttng/abi.h>
23 #include <lttng/abi-old.h>
24 #include <lttng/endian.h>
26 #define lttng_is_signed_type(type) (((type) -1) < (type) 1)
28 struct lttng_kernel_channel_buffer
;
29 struct lttng_kernel_session
;
30 struct lttng_kernel_ring_buffer_ctx
;
32 /* Type description */
34 enum lttng_kernel_type
{
35 lttng_kernel_type_integer
,
36 lttng_kernel_type_string
,
37 lttng_kernel_type_enum
,
38 lttng_kernel_type_array
,
39 lttng_kernel_type_sequence
,
40 lttng_kernel_type_struct
,
41 lttng_kernel_type_variant
,
42 NR_LTTNG_KERNEL_TYPES
,
45 enum lttng_kernel_string_encoding
{
46 lttng_kernel_string_encoding_none
= 0,
47 lttng_kernel_string_encoding_UTF8
= 1,
48 lttng_kernel_string_encoding_ASCII
= 2,
49 NR_LTTNG_KERNEL_STRING_ENCODING
,
52 struct lttng_kernel_enum_value
{
53 unsigned long long value
;
54 unsigned int signedness
:1;
57 struct lttng_kernel_enum_entry
{
58 struct lttng_kernel_enum_value start
, end
; /* start and end are inclusive */
61 unsigned int is_auto
:1;
66 * struct lttng_kernel_type_common is fixed-size. Its children inherits
67 * from it by embedding struct lttng_kernel_type_common as its first field.
69 struct lttng_kernel_type_common
{
70 enum lttng_kernel_type type
;
73 struct lttng_kernel_type_integer
{
74 struct lttng_kernel_type_common parent
;
75 unsigned int size
; /* in bits */
76 unsigned short alignment
; /* in bits */
77 unsigned int signedness
:1,
79 unsigned int base
; /* 2, 8, 10, 16, for pretty print */
82 struct lttng_kernel_type_string
{
83 struct lttng_kernel_type_common parent
;
84 enum lttng_kernel_string_encoding encoding
;
87 struct lttng_kernel_type_enum
{
88 struct lttng_kernel_type_common parent
;
89 const struct lttng_kernel_enum_desc
*desc
; /* Enumeration mapping */
90 const struct lttng_kernel_type_common
*container_type
;
93 struct lttng_kernel_type_array
{
94 struct lttng_kernel_type_common parent
;
95 const struct lttng_kernel_type_common
*elem_type
;
96 unsigned int length
; /* Num. elems. */
97 unsigned int alignment
;
98 enum lttng_kernel_string_encoding encoding
;
101 struct lttng_kernel_type_sequence
{
102 struct lttng_kernel_type_common parent
;
103 const char *length_name
; /* Length field name. If NULL, use previous field. */
104 const struct lttng_kernel_type_common
*elem_type
;
105 unsigned int alignment
; /* Alignment before elements. */
106 enum lttng_kernel_string_encoding encoding
;
109 struct lttng_kernel_type_struct
{
110 struct lttng_kernel_type_common parent
;
111 unsigned int nr_fields
;
112 const struct lttng_kernel_event_field
* const *fields
; /* Array of pointers to fields. */
113 unsigned int alignment
;
116 struct lttng_kernel_type_variant
{
117 struct lttng_kernel_type_common parent
;
118 const char *tag_name
; /* Tag field name. If NULL, use previous field. */
119 const struct lttng_kernel_event_field
* const *choices
; /* Array of pointers to fields. */
120 unsigned int nr_choices
;
121 unsigned int alignment
;
124 struct lttng_kernel_enum_desc
{
126 const struct lttng_kernel_enum_entry
* const *entries
;
127 unsigned int nr_entries
;
128 const struct lttng_kernel_probe_desc
*probe_desc
;
131 /* Event field description */
133 struct lttng_kernel_event_field
{
135 const struct lttng_kernel_type_common
*type
;
136 unsigned int nowrite
:1, /* do not write into trace */
137 user
:1, /* fetch from user-space */
138 nofilter
:1; /* do not consider for filter */
142 #define PARAMS(args...) args
145 #define lttng_kernel_static_type_integer(_size, _alignment, _signedness, _byte_order, _base) \
146 ((const struct lttng_kernel_type_common *) __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_type_integer, { \
148 .type = lttng_kernel_type_integer, \
151 .alignment = (_alignment), \
152 .signedness = (_signedness), \
153 .reverse_byte_order = (_byte_order) != __BYTE_ORDER, \
157 #define lttng_kernel_static_type_integer_from_type(_type, _byte_order, _base) \
158 lttng_kernel_static_type_integer(sizeof(_type) * CHAR_BIT, \
159 lttng_alignof(_type) * CHAR_BIT, \
160 lttng_is_signed_type(_type), \
164 #define lttng_kernel_static_type_enum(_desc, _container_type) \
165 ((const struct lttng_kernel_type_common *) __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_type_enum, { \
167 .type = lttng_kernel_type_enum, \
170 .container_type = (_container_type), \
173 #define lttng_kernel_static_type_array(_length, _elem_type, _alignment, _encoding) \
174 ((const struct lttng_kernel_type_common *) __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_type_array, { \
176 .type = lttng_kernel_type_array, \
178 .length = (_length), \
179 .alignment = (_alignment), \
180 .encoding = lttng_kernel_string_encoding_##_encoding, \
181 .elem_type = (_elem_type), \
184 #define lttng_kernel_static_type_array_text(_length) \
185 lttng_kernel_static_type_array(_length, \
186 lttng_kernel_static_type_integer(sizeof(char) * CHAR_BIT, \
187 lttng_alignof(char) * CHAR_BIT, lttng_is_signed_type(char), \
191 #define lttng_kernel_static_type_sequence(_length_name, _elem_type, _alignment, _encoding) \
192 ((const struct lttng_kernel_type_common *) __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_type_sequence, { \
194 .type = lttng_kernel_type_sequence, \
196 .length_name = (_length_name), \
197 .alignment = (_alignment), \
198 .encoding = lttng_kernel_string_encoding_##_encoding, \
199 .elem_type = (_elem_type), \
202 #define lttng_kernel_static_type_string(_encoding) \
203 ((const struct lttng_kernel_type_common *) __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_type_string, { \
205 .type = lttng_kernel_type_string, \
207 .encoding = lttng_kernel_string_encoding_##_encoding, \
210 #define lttng_kernel_static_type_struct_init(_nr_fields, _fields, _alignment) \
213 .type = lttng_kernel_type_struct, \
215 .nr_fields = (_nr_fields), \
217 .alignment = (_alignment), \
220 #define lttng_kernel_static_type_struct(_nr_fields, _fields, _alignment) \
221 ((const struct lttng_kernel_type_common *) __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_type_struct, \
222 lttng_kernel_static_type_struct_init(_nr_fields, PARAMS(_fields), _alignment) \
225 #define lttng_kernel_static_type_variant(_nr_choices, _choices, _tag_name, _alignment) \
226 ((const struct lttng_kernel_type_common *) __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_type_variant, { \
228 .type = lttng_kernel_type_variant, \
230 .tag_name = (_tag_name), \
231 .choices = _choices, \
232 .nr_choices = (_nr_choices), \
233 .alignment = (_alignment), \
236 #define lttng_kernel_static_event_field(_name, _type, _nowrite, _user, _nofilter) \
237 __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_event_field, { \
240 .nowrite = (_nowrite), \
242 .nofilter = (_nofilter), \
245 #define lttng_kernel_static_event_field_array(_fields...) \
246 __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_event_field *, \
250 #define lttng_kernel_static_enum_entry_value(_string, _value) \
251 __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_enum_entry, { \
253 .signedness = lttng_is_signed_type(__typeof__(_value)), \
254 .value = lttng_is_signed_type(__typeof__(_value)) ? \
255 (long long) (_value) : (_value), \
258 .signedness = lttng_is_signed_type(__typeof__(_value)), \
259 .value = lttng_is_signed_type(__typeof__(_value)) ? \
260 (long long) (_value) : (_value), \
262 .string = (_string), \
265 #define lttng_kernel_static_enum_entry_range(_string, _range_start, _range_end) \
266 __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_enum_entry, { \
268 .signedness = lttng_is_signed_type(__typeof__(_range_start)), \
269 .value = lttng_is_signed_type(__typeof__(_range_start)) ? \
270 (long long) (_range_start) : (_range_start), \
273 .signedness = lttng_is_signed_type(__typeof__(_range_end)), \
274 .value = lttng_is_signed_type(__typeof__(_range_end)) ? \
275 (long long) (_range_end) : (_range_end), \
277 .string = (_string), \
280 #define lttng_kernel_static_enum_entry_auto(_string) \
281 __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_enum_entry, { \
290 .string = (_string), \
296 struct lttng_kernel_probe_ctx
{
297 struct lttng_kernel_event_common
*event
;
298 uint8_t interruptible
;
301 struct lttng_kernel_tracepoint_class
{
302 void (*probe_callback
)(void);
303 const struct lttng_kernel_event_field
* const *fields
; /* event payload */
304 unsigned int nr_fields
;
305 const struct lttng_kernel_probe_desc
*probe_desc
;
308 struct lttng_kernel_event_desc
{
309 const char *event_name
; /* lttng-modules name */
310 const char *event_kname
; /* Linux kernel name (tracepoints) */
311 const struct lttng_kernel_probe_desc
*probe_desc
;
312 const struct lttng_kernel_tracepoint_class
*tp_class
;
313 struct module
*owner
;
316 struct lttng_kernel_probe_desc
{
317 const char *provider_name
;
318 const struct lttng_kernel_event_desc
* const *event_desc
;
319 unsigned int nr_events
;
320 struct list_head head
; /* chain registered probes */
321 struct list_head lazy_init_head
;
322 int lazy
; /* lazy registration */
326 * Result of the run_filter() callback.
328 enum lttng_kernel_event_filter_result
{
329 LTTNG_KERNEL_EVENT_FILTER_ACCEPT
= 0,
330 LTTNG_KERNEL_EVENT_FILTER_REJECT
= 1,
333 struct lttng_kernel_event_common_private
;
335 enum lttng_kernel_event_type
{
336 LTTNG_KERNEL_EVENT_TYPE_RECORDER
= 0,
337 LTTNG_KERNEL_EVENT_TYPE_NOTIFIER
= 1,
340 struct lttng_kernel_event_common
{
341 struct lttng_kernel_event_common_private
*priv
; /* Private event interface */
343 enum lttng_kernel_event_type type
;
344 /* Get child with container_of(). */
347 int eval_filter
; /* Need to evaluate filters */
348 int (*run_filter
)(const struct lttng_kernel_event_common
*event
,
349 const char *stack_data
,
350 struct lttng_kernel_probe_ctx
*probe_ctx
,
354 struct lttng_kernel_event_recorder_private
;
356 struct lttng_kernel_event_recorder
{
357 struct lttng_kernel_event_common parent
;
358 struct lttng_kernel_event_recorder_private
*priv
; /* Private event record interface */
360 struct lttng_kernel_channel_buffer
*chan
;
363 struct lttng_kernel_notification_ctx
{
364 int eval_capture
; /* Capture evaluation available. */
367 struct lttng_kernel_event_notifier_private
;
369 struct lttng_kernel_event_notifier
{
370 struct lttng_kernel_event_common parent
;
371 struct lttng_kernel_event_notifier_private
*priv
; /* Private event notifier interface */
373 int eval_capture
; /* Need to evaluate capture */
374 void (*notification_send
)(struct lttng_kernel_event_notifier
*event_notifier
,
375 const char *stack_data
,
376 struct lttng_kernel_probe_ctx
*probe_ctx
,
377 struct lttng_kernel_notification_ctx
*notif_ctx
);
380 struct lttng_kernel_channel_buffer_ops
{
381 struct lttng_kernel_channel_buffer_ops_private
*priv
; /* Private channel buffer ops interface. */
383 int (*event_reserve
)(struct lttng_kernel_ring_buffer_ctx
*ctx
);
384 void (*event_commit
)(struct lttng_kernel_ring_buffer_ctx
*ctx
);
385 void (*event_write
)(struct lttng_kernel_ring_buffer_ctx
*ctx
, const void *src
,
387 void (*event_write_from_user
)(struct lttng_kernel_ring_buffer_ctx
*ctx
,
388 const void *src
, size_t len
);
389 void (*event_memset
)(struct lttng_kernel_ring_buffer_ctx
*ctx
,
391 void (*event_strcpy
)(struct lttng_kernel_ring_buffer_ctx
*ctx
, const char *src
,
393 void (*event_strcpy_from_user
)(struct lttng_kernel_ring_buffer_ctx
*ctx
,
394 const char __user
*src
, size_t len
);
395 void (*lost_event_too_big
)(struct lttng_kernel_channel_buffer
*lttng_channel
);
398 enum lttng_kernel_channel_type
{
399 LTTNG_KERNEL_CHANNEL_TYPE_BUFFER
= 0,
402 struct lttng_kernel_channel_common_private
;
404 /* Use container_of() to get child. */
405 struct lttng_kernel_channel_common
{
406 struct lttng_kernel_channel_common_private
*priv
; /* Private channel interface. */
408 enum lttng_kernel_channel_type type
;
411 struct lttng_kernel_session
*session
;
414 struct lttng_kernel_channel_buffer_private
;
416 struct lttng_kernel_channel_buffer
{
417 struct lttng_kernel_channel_common parent
;
418 struct lttng_kernel_channel_buffer_private
*priv
;
420 struct lttng_kernel_channel_buffer_ops
*ops
;
423 #define LTTNG_DYNAMIC_LEN_STACK_SIZE 128
425 struct lttng_dynamic_len_stack
{
426 size_t stack
[LTTNG_DYNAMIC_LEN_STACK_SIZE
];
430 DECLARE_PER_CPU(struct lttng_dynamic_len_stack
, lttng_dynamic_len_stack
);
433 * struct lttng_kernel_id_tracker declared in header due to deferencing of *v
434 * in RCU_INITIALIZER(v).
436 #define LTTNG_ID_HASH_BITS 6
437 #define LTTNG_ID_TABLE_SIZE (1 << LTTNG_ID_HASH_BITS)
439 struct lttng_kernel_id_tracker_rcu
{
440 struct hlist_head id_hash
[LTTNG_ID_TABLE_SIZE
];
443 struct lttng_kernel_id_tracker
{
444 struct lttng_kernel_id_tracker_private
*priv
; /* Private API */
446 struct lttng_kernel_id_tracker_rcu
*p
; /* RCU dereferenced. */
449 struct lttng_kernel_session_private
;
451 struct lttng_kernel_session
{
452 struct lttng_kernel_session_private
*priv
; /* Private session interface */
454 int active
; /* Is trace session active ? */
456 struct lttng_kernel_id_tracker pid_tracker
;
457 struct lttng_kernel_id_tracker vpid_tracker
;
458 struct lttng_kernel_id_tracker uid_tracker
;
459 struct lttng_kernel_id_tracker vuid_tracker
;
460 struct lttng_kernel_id_tracker gid_tracker
;
461 struct lttng_kernel_id_tracker vgid_tracker
;
464 int lttng_kernel_probe_register(struct lttng_kernel_probe_desc
*desc
);
465 void lttng_kernel_probe_unregister(struct lttng_kernel_probe_desc
*desc
);
467 bool lttng_id_tracker_lookup(struct lttng_kernel_id_tracker_rcu
*p
, int id
);
469 #endif /* _LTTNG_EVENTS_H */