| 1 | /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only) |
| 2 | * |
| 3 | * lttng/events.h |
| 4 | * |
| 5 | * Holds LTTng per-session event registry. |
| 6 | * |
| 7 | * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 8 | */ |
| 9 | |
| 10 | #ifndef _LTTNG_EVENTS_H |
| 11 | #define _LTTNG_EVENTS_H |
| 12 | |
| 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> |
| 25 | |
| 26 | #define lttng_is_signed_type(type) (((type) -1) < (type) 1) |
| 27 | |
| 28 | struct lttng_kernel_channel_buffer; |
| 29 | struct lttng_kernel_session; |
| 30 | struct lttng_kernel_ring_buffer_ctx; |
| 31 | |
| 32 | /* Type description */ |
| 33 | |
| 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, |
| 43 | }; |
| 44 | |
| 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, |
| 50 | }; |
| 51 | |
| 52 | struct lttng_kernel_enum_value { |
| 53 | unsigned long long value; |
| 54 | unsigned int signedness:1; |
| 55 | }; |
| 56 | |
| 57 | struct lttng_kernel_enum_entry { |
| 58 | struct lttng_kernel_enum_value start, end; /* start and end are inclusive */ |
| 59 | const char *string; |
| 60 | struct { |
| 61 | unsigned int is_auto:1; |
| 62 | } options; |
| 63 | }; |
| 64 | |
| 65 | /* |
| 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. |
| 68 | */ |
| 69 | struct lttng_kernel_type_common { |
| 70 | enum lttng_kernel_type type; |
| 71 | }; |
| 72 | |
| 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, |
| 78 | reverse_byte_order:1; |
| 79 | unsigned int base; /* 2, 8, 10, 16, for pretty print */ |
| 80 | }; |
| 81 | |
| 82 | struct lttng_kernel_type_string { |
| 83 | struct lttng_kernel_type_common parent; |
| 84 | enum lttng_kernel_string_encoding encoding; |
| 85 | }; |
| 86 | |
| 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; |
| 91 | }; |
| 92 | |
| 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; |
| 99 | }; |
| 100 | |
| 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; |
| 107 | }; |
| 108 | |
| 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; |
| 114 | }; |
| 115 | |
| 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; |
| 122 | }; |
| 123 | |
| 124 | struct lttng_kernel_enum_desc { |
| 125 | const char *name; |
| 126 | const struct lttng_kernel_enum_entry * const *entries; |
| 127 | unsigned int nr_entries; |
| 128 | const struct lttng_kernel_probe_desc *probe_desc; |
| 129 | }; |
| 130 | |
| 131 | /* Event field description */ |
| 132 | |
| 133 | struct lttng_kernel_event_field { |
| 134 | const char *name; |
| 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 */ |
| 139 | }; |
| 140 | |
| 141 | #ifndef PARAMS |
| 142 | #define PARAMS(args...) args |
| 143 | #endif |
| 144 | |
| 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, { \ |
| 147 | .parent = { \ |
| 148 | .type = lttng_kernel_type_integer, \ |
| 149 | }, \ |
| 150 | .size = (_size), \ |
| 151 | .alignment = (_alignment), \ |
| 152 | .signedness = (_signedness), \ |
| 153 | .reverse_byte_order = (_byte_order) != __BYTE_ORDER, \ |
| 154 | .base = (_base), \ |
| 155 | })) |
| 156 | |
| 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), \ |
| 161 | _byte_order, \ |
| 162 | _base) |
| 163 | |
| 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, { \ |
| 166 | .parent = { \ |
| 167 | .type = lttng_kernel_type_enum, \ |
| 168 | }, \ |
| 169 | .desc = (_desc), \ |
| 170 | .container_type = (_container_type), \ |
| 171 | })) |
| 172 | |
| 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, { \ |
| 175 | .parent = { \ |
| 176 | .type = lttng_kernel_type_array, \ |
| 177 | }, \ |
| 178 | .length = (_length), \ |
| 179 | .alignment = (_alignment), \ |
| 180 | .encoding = lttng_kernel_string_encoding_##_encoding, \ |
| 181 | .elem_type = (_elem_type), \ |
| 182 | })) |
| 183 | |
| 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), \ |
| 188 | __BYTE_ORDER, 10), \ |
| 189 | 0, UTF8) |
| 190 | |
| 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, { \ |
| 193 | .parent = { \ |
| 194 | .type = lttng_kernel_type_sequence, \ |
| 195 | }, \ |
| 196 | .length_name = (_length_name), \ |
| 197 | .alignment = (_alignment), \ |
| 198 | .encoding = lttng_kernel_string_encoding_##_encoding, \ |
| 199 | .elem_type = (_elem_type), \ |
| 200 | })) |
| 201 | |
| 202 | #define lttng_kernel_static_type_string(_encoding) \ |
| 203 | ((const struct lttng_kernel_type_common *) __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_type_string, { \ |
| 204 | .parent = { \ |
| 205 | .type = lttng_kernel_type_string, \ |
| 206 | }, \ |
| 207 | .encoding = lttng_kernel_string_encoding_##_encoding, \ |
| 208 | })) |
| 209 | |
| 210 | #define lttng_kernel_static_type_struct_init(_nr_fields, _fields, _alignment) \ |
| 211 | { \ |
| 212 | .parent = { \ |
| 213 | .type = lttng_kernel_type_struct, \ |
| 214 | }, \ |
| 215 | .nr_fields = (_nr_fields), \ |
| 216 | .fields = _fields, \ |
| 217 | .alignment = (_alignment), \ |
| 218 | } |
| 219 | |
| 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) \ |
| 223 | )) |
| 224 | |
| 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, { \ |
| 227 | .parent = { \ |
| 228 | .type = lttng_kernel_type_variant, \ |
| 229 | }, \ |
| 230 | .tag_name = (_tag_name), \ |
| 231 | .choices = _choices, \ |
| 232 | .nr_choices = (_nr_choices), \ |
| 233 | .alignment = (_alignment), \ |
| 234 | })) |
| 235 | |
| 236 | #define lttng_kernel_static_event_field(_name, _type, _nowrite, _user, _nofilter) \ |
| 237 | __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_event_field, { \ |
| 238 | .name = (_name), \ |
| 239 | .type = (_type), \ |
| 240 | .nowrite = (_nowrite), \ |
| 241 | .user = (_user), \ |
| 242 | .nofilter = (_nofilter), \ |
| 243 | }) |
| 244 | |
| 245 | #define lttng_kernel_static_event_field_array(_fields...) \ |
| 246 | __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_event_field *, \ |
| 247 | _fields \ |
| 248 | ) |
| 249 | |
| 250 | #define lttng_kernel_static_enum_entry_value(_string, _value) \ |
| 251 | __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_enum_entry, { \ |
| 252 | .start = { \ |
| 253 | .signedness = lttng_is_signed_type(__typeof__(_value)), \ |
| 254 | .value = lttng_is_signed_type(__typeof__(_value)) ? \ |
| 255 | (long long) (_value) : (_value), \ |
| 256 | }, \ |
| 257 | .end = { \ |
| 258 | .signedness = lttng_is_signed_type(__typeof__(_value)), \ |
| 259 | .value = lttng_is_signed_type(__typeof__(_value)) ? \ |
| 260 | (long long) (_value) : (_value), \ |
| 261 | }, \ |
| 262 | .string = (_string), \ |
| 263 | }), |
| 264 | |
| 265 | #define lttng_kernel_static_enum_entry_range(_string, _range_start, _range_end) \ |
| 266 | __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_enum_entry, { \ |
| 267 | .start = { \ |
| 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), \ |
| 271 | }, \ |
| 272 | .end = { \ |
| 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), \ |
| 276 | }, \ |
| 277 | .string = (_string), \ |
| 278 | }), |
| 279 | |
| 280 | #define lttng_kernel_static_enum_entry_auto(_string) \ |
| 281 | __LTTNG_COMPOUND_LITERAL(const struct lttng_kernel_enum_entry, { \ |
| 282 | .start = { \ |
| 283 | .signedness = -1, \ |
| 284 | .value = -1, \ |
| 285 | }, \ |
| 286 | .end = { \ |
| 287 | .signedness = -1, \ |
| 288 | .value = -1, \ |
| 289 | }, \ |
| 290 | .string = (_string), \ |
| 291 | .options = { \ |
| 292 | .is_auto = 1, \ |
| 293 | } \ |
| 294 | }), |
| 295 | |
| 296 | struct lttng_kernel_probe_ctx { |
| 297 | struct lttng_kernel_event_common *event; |
| 298 | uint8_t interruptible; |
| 299 | }; |
| 300 | |
| 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; |
| 306 | }; |
| 307 | |
| 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; |
| 314 | }; |
| 315 | |
| 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 */ |
| 323 | }; |
| 324 | |
| 325 | /* |
| 326 | * Result of the run_filter() callback. |
| 327 | */ |
| 328 | enum lttng_kernel_event_filter_result { |
| 329 | LTTNG_KERNEL_EVENT_FILTER_ACCEPT = 0, |
| 330 | LTTNG_KERNEL_EVENT_FILTER_REJECT = 1, |
| 331 | }; |
| 332 | |
| 333 | struct lttng_kernel_event_common_private; |
| 334 | |
| 335 | enum lttng_kernel_event_type { |
| 336 | LTTNG_KERNEL_EVENT_TYPE_RECORDER = 0, |
| 337 | LTTNG_KERNEL_EVENT_TYPE_NOTIFIER = 1, |
| 338 | }; |
| 339 | |
| 340 | struct lttng_kernel_event_common { |
| 341 | struct lttng_kernel_event_common_private *priv; /* Private event interface */ |
| 342 | |
| 343 | enum lttng_kernel_event_type type; |
| 344 | /* Get child with container_of(). */ |
| 345 | |
| 346 | int enabled; |
| 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, |
| 351 | void *filter_ctx); |
| 352 | }; |
| 353 | |
| 354 | struct lttng_kernel_event_recorder_private; |
| 355 | |
| 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 */ |
| 359 | |
| 360 | struct lttng_kernel_channel_buffer *chan; |
| 361 | }; |
| 362 | |
| 363 | struct lttng_kernel_notification_ctx { |
| 364 | int eval_capture; /* Capture evaluation available. */ |
| 365 | }; |
| 366 | |
| 367 | struct lttng_kernel_event_notifier_private; |
| 368 | |
| 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 */ |
| 372 | |
| 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); |
| 378 | }; |
| 379 | |
| 380 | struct lttng_kernel_channel_buffer_ops { |
| 381 | struct lttng_kernel_channel_buffer_ops_private *priv; /* Private channel buffer ops interface. */ |
| 382 | |
| 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, |
| 386 | size_t len, size_t alignment); |
| 387 | void (*event_write_from_user)(struct lttng_kernel_ring_buffer_ctx *ctx, |
| 388 | const void *src, size_t len, size_t alignment); |
| 389 | void (*event_memset)(struct lttng_kernel_ring_buffer_ctx *ctx, |
| 390 | int c, size_t len); |
| 391 | void (*event_strcpy)(struct lttng_kernel_ring_buffer_ctx *ctx, const char *src, |
| 392 | size_t len); |
| 393 | void (*event_strcpy_from_user)(struct lttng_kernel_ring_buffer_ctx *ctx, |
| 394 | const char __user *src, size_t len); |
| 395 | void (*event_pstrcpy_pad)(struct lttng_kernel_ring_buffer_ctx *ctx, |
| 396 | const char *src, size_t len); |
| 397 | void (*event_pstrcpy_pad_from_user)(struct lttng_kernel_ring_buffer_ctx *ctx, |
| 398 | const char __user *src, size_t len); |
| 399 | void (*lost_event_too_big)(struct lttng_kernel_channel_buffer *lttng_channel); |
| 400 | }; |
| 401 | |
| 402 | enum lttng_kernel_channel_type { |
| 403 | LTTNG_KERNEL_CHANNEL_TYPE_BUFFER = 0, |
| 404 | }; |
| 405 | |
| 406 | struct lttng_kernel_channel_common_private; |
| 407 | |
| 408 | /* Use container_of() to get child. */ |
| 409 | struct lttng_kernel_channel_common { |
| 410 | struct lttng_kernel_channel_common_private *priv; /* Private channel interface. */ |
| 411 | |
| 412 | enum lttng_kernel_channel_type type; |
| 413 | |
| 414 | int enabled; |
| 415 | struct lttng_kernel_session *session; |
| 416 | }; |
| 417 | |
| 418 | struct lttng_kernel_channel_buffer_private; |
| 419 | |
| 420 | struct lttng_kernel_channel_buffer { |
| 421 | struct lttng_kernel_channel_common parent; |
| 422 | struct lttng_kernel_channel_buffer_private *priv; |
| 423 | |
| 424 | struct lttng_kernel_channel_buffer_ops *ops; |
| 425 | }; |
| 426 | |
| 427 | #define LTTNG_DYNAMIC_LEN_STACK_SIZE 128 |
| 428 | |
| 429 | struct lttng_dynamic_len_stack { |
| 430 | size_t stack[LTTNG_DYNAMIC_LEN_STACK_SIZE]; |
| 431 | size_t offset; |
| 432 | }; |
| 433 | |
| 434 | DECLARE_PER_CPU(struct lttng_dynamic_len_stack, lttng_dynamic_len_stack); |
| 435 | |
| 436 | /* |
| 437 | * struct lttng_kernel_id_tracker declared in header due to deferencing of *v |
| 438 | * in RCU_INITIALIZER(v). |
| 439 | */ |
| 440 | #define LTTNG_ID_HASH_BITS 6 |
| 441 | #define LTTNG_ID_TABLE_SIZE (1 << LTTNG_ID_HASH_BITS) |
| 442 | |
| 443 | struct lttng_kernel_id_tracker_rcu { |
| 444 | struct hlist_head id_hash[LTTNG_ID_TABLE_SIZE]; |
| 445 | }; |
| 446 | |
| 447 | struct lttng_kernel_id_tracker { |
| 448 | struct lttng_kernel_id_tracker_private *priv; /* Private API */ |
| 449 | |
| 450 | struct lttng_kernel_id_tracker_rcu *p; /* RCU dereferenced. */ |
| 451 | }; |
| 452 | |
| 453 | struct lttng_kernel_session_private; |
| 454 | |
| 455 | struct lttng_kernel_session { |
| 456 | struct lttng_kernel_session_private *priv; /* Private session interface */ |
| 457 | |
| 458 | int active; /* Is trace session active ? */ |
| 459 | |
| 460 | struct lttng_kernel_id_tracker pid_tracker; |
| 461 | struct lttng_kernel_id_tracker vpid_tracker; |
| 462 | struct lttng_kernel_id_tracker uid_tracker; |
| 463 | struct lttng_kernel_id_tracker vuid_tracker; |
| 464 | struct lttng_kernel_id_tracker gid_tracker; |
| 465 | struct lttng_kernel_id_tracker vgid_tracker; |
| 466 | }; |
| 467 | |
| 468 | int lttng_kernel_probe_register(struct lttng_kernel_probe_desc *desc); |
| 469 | void lttng_kernel_probe_unregister(struct lttng_kernel_probe_desc *desc); |
| 470 | |
| 471 | bool lttng_id_tracker_lookup(struct lttng_kernel_id_tracker_rcu *p, int id); |
| 472 | |
| 473 | #endif /* _LTTNG_EVENTS_H */ |