include/lttng/events.h

   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 <linux/irq_work.h>
  14 #include <linux/version.h>
  15 #include <linux/list.h>
  16 #include <linux/kprobes.h>
  17 #include <linux/kref.h>
  18 #include <linux/uuid.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)) < 0)
  27
  28 struct lttng_channel;
  29 struct lttng_session;
  30 struct lttng_metadata_cache;
  31 struct lib_ring_buffer_ctx;
  32 struct perf_event;
  33 struct perf_event_attr;
  34 struct lib_ring_buffer_config;
  35
  36 /* Type description */
  37
  38 enum abstract_types {
  39         atype_integer,
  40         atype_string,
  41         atype_enum_nestable,
  42         atype_array_nestable,
  43         atype_sequence_nestable,
  44         atype_struct_nestable,
  45         atype_variant_nestable,
  46         NR_ABSTRACT_TYPES,
  47 };
  48
  49 enum lttng_string_encodings {
  50         lttng_encode_none = 0,
  51         lttng_encode_UTF8 = 1,
  52         lttng_encode_ASCII = 2,
  53         NR_STRING_ENCODINGS,
  54 };
  55
  56 enum channel_type {
  57         PER_CPU_CHANNEL,
  58         METADATA_CHANNEL,
  59 };
  60
  61 struct lttng_enum_value {
  62         unsigned long long value;
  63         unsigned int signedness:1;
  64 };
  65
  66 struct lttng_enum_entry {
  67         struct lttng_enum_value start, end;     /* start and end are inclusive */
  68         const char *string;
  69         struct {
  70                 unsigned int is_auto:1;
  71         } options;
  72 };
  73
  74 #define __type_integer(_type, _size, _alignment, _signedness,   \
  75                 _byte_order, _base, _encoding)  \
  76         {                                                       \
  77             .atype = atype_integer,                             \
  78             .u.integer =                                        \
  79                 {                                               \
  80                   .size = (_size) ? : sizeof(_type) * CHAR_BIT, \
  81                   .alignment = (_alignment) ? : lttng_alignof(_type) * CHAR_BIT, \
  82                   .signedness = (_signedness) >= 0 ? (_signedness) : lttng_is_signed_type(_type), \
  83                   .reverse_byte_order = _byte_order != __BYTE_ORDER, \
  84                   .base = _base,                                \
  85                   .encoding = lttng_encode_##_encoding,         \
  86                 },                                              \
  87         }                                                       \
  88
  89 struct lttng_integer_type {
  90         unsigned int size;              /* in bits */
  91         unsigned short alignment;       /* in bits */
  92         unsigned int signedness:1,
  93                 reverse_byte_order:1;
  94         unsigned int base;              /* 2, 8, 10, 16, for pretty print */
  95         enum lttng_string_encodings encoding;
  96 };
  97
  98 struct lttng_type {
  99         enum abstract_types atype;
 100         union {
 101                 struct lttng_integer_type integer;
 102                 struct {
 103                         enum lttng_string_encodings encoding;
 104                 } string;
 105                 struct {
 106                         const struct lttng_enum_desc *desc;     /* Enumeration mapping */
 107                         const struct lttng_type *container_type;
 108                 } enum_nestable;
 109                 struct {
 110                         const struct lttng_type *elem_type;
 111                         unsigned int length;                    /* Num. elems. */
 112                         unsigned int alignment;
 113                 } array_nestable;
 114                 struct {
 115                         const char *length_name;                /* Length field name. */
 116                         const struct lttng_type *elem_type;
 117                         unsigned int alignment;                 /* Alignment before elements. */
 118                 } sequence_nestable;
 119                 struct {
 120                         unsigned int nr_fields;
 121                         const struct lttng_event_field *fields; /* Array of fields. */
 122                         unsigned int alignment;
 123                 } struct_nestable;
 124                 struct {
 125                         const char *tag_name;
 126                         const struct lttng_event_field *choices; /* Array of fields. */
 127                         unsigned int nr_choices;
 128                         unsigned int alignment;
 129                 } variant_nestable;
 130         } u;
 131 };
 132
 133 struct lttng_enum_desc {
 134         const char *name;
 135         const struct lttng_enum_entry *entries;
 136         unsigned int nr_entries;
 137 };
 138
 139 /* Event field description */
 140
 141 struct lttng_event_field {
 142         const char *name;
 143         struct lttng_type type;
 144         unsigned int nowrite:1,         /* do not write into trace */
 145                         user:1,         /* fetch from user-space */
 146                         nofilter:1;     /* do not consider for filter */
 147 };
 148
 149 union lttng_ctx_value {
 150         int64_t s64;
 151         const char *str;
 152         double d;
 153 };
 154
 155 /*
 156  * We need to keep this perf counter field separately from struct
 157  * lttng_ctx_field because cpu hotplug needs fixed-location addresses.
 158  */
 159 struct lttng_perf_counter_field {
 160 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))
 161         struct lttng_cpuhp_node cpuhp_prepare;
 162         struct lttng_cpuhp_node cpuhp_online;
 163 #else
 164         struct notifier_block nb;
 165         int hp_enable;
 166 #endif
 167         struct perf_event_attr *attr;
 168         struct perf_event **e;  /* per-cpu array */
 169 };
 170
 171 struct lttng_probe_ctx {
 172         struct lttng_event *event;
 173         struct lttng_event_notifier *event_notifier; // Not sure if we will ever need it.
 174         uint8_t interruptible;
 175 };
 176
 177 struct lttng_ctx_field {
 178         struct lttng_event_field event_field;
 179         size_t (*get_size)(size_t offset);
 180         size_t (*get_size_arg)(size_t offset, struct lttng_ctx_field *field,
 181                                struct lib_ring_buffer_ctx *ctx,
 182                                struct lttng_channel *chan);
 183         void (*record)(struct lttng_ctx_field *field,
 184                        struct lib_ring_buffer_ctx *ctx,
 185                        struct lttng_channel *chan);
 186         void (*get_value)(struct lttng_ctx_field *field,
 187                          struct lttng_probe_ctx *lttng_probe_ctx,
 188                          union lttng_ctx_value *value);
 189         union {
 190                 struct lttng_perf_counter_field *perf_counter;
 191         } u;
 192         void (*destroy)(struct lttng_ctx_field *field);
 193         /*
 194          * Private data to keep state between get_size and record.
 195          * User must perform its own synchronization to protect against
 196          * concurrent and reentrant contexts.
 197          */
 198         void *priv;
 199 };
 200
 201 struct lttng_ctx {
 202         struct lttng_ctx_field *fields;
 203         unsigned int nr_fields;
 204         unsigned int allocated_fields;
 205         size_t largest_align;   /* in bytes */
 206 };
 207
 208 struct lttng_event_desc {
 209         const char *name;               /* lttng-modules name */
 210         const char *kname;              /* Linux kernel name (tracepoints) */
 211         void *probe_callback;
 212         const struct lttng_event_ctx *ctx;      /* context */
 213         const struct lttng_event_field *fields; /* event payload */
 214         unsigned int nr_fields;
 215         struct module *owner;
 216         void *event_notifier_callback;
 217 };
 218
 219 struct lttng_probe_desc {
 220         const char *provider;
 221         const struct lttng_event_desc **event_desc;
 222         unsigned int nr_events;
 223         struct list_head head;                  /* chain registered probes */
 224         struct list_head lazy_init_head;
 225         int lazy;                               /* lazy registration */
 226 };
 227
 228 struct lttng_krp;                               /* Kretprobe handling */
 229
 230 enum lttng_event_type {
 231         LTTNG_TYPE_EVENT = 0,
 232         LTTNG_TYPE_ENABLER = 1,
 233 };
 234
 235 struct lttng_filter_bytecode_node {
 236         struct list_head node;
 237         struct lttng_enabler *enabler;
 238         /*
 239          * struct lttng_kernel_filter_bytecode has var. sized array, must be
 240          * last field.
 241          */
 242         struct lttng_kernel_filter_bytecode bc;
 243 };
 244
 245 /*
 246  * Filter return value masks.
 247  */
 248 enum lttng_filter_ret {
 249         LTTNG_FILTER_DISCARD = 0,
 250         LTTNG_FILTER_RECORD_FLAG = (1ULL << 0),
 251         /* Other bits are kept for future use. */
 252 };
 253
 254 struct lttng_bytecode_runtime {
 255         /* Associated bytecode */
 256         struct lttng_filter_bytecode_node *bc;
 257         uint64_t (*filter)(void *filter_data, struct lttng_probe_ctx *lttng_probe_ctx,
 258                         const char *filter_stack_data);
 259         int link_failed;
 260         struct list_head node;  /* list of bytecode runtime in event */
 261         struct lttng_ctx *ctx;
 262 };
 263
 264 /*
 265  * Objects in a linked-list of enablers, owned by an event.
 266  */
 267 struct lttng_enabler_ref {
 268         struct list_head node;                  /* enabler ref list */
 269         struct lttng_enabler *ref;              /* backward ref */
 270 };
 271
 272 struct lttng_uprobe_handler {
 273         struct lttng_event *event;
 274         loff_t offset;
 275         struct uprobe_consumer up_consumer;
 276         struct list_head node;
 277 };
 278
 279 struct lttng_kprobe {
 280         struct kprobe kp;
 281         char *symbol_name;
 282 };
 283
 284 enum lttng_syscall_entryexit {
 285         LTTNG_SYSCALL_ENTRY,
 286         LTTNG_SYSCALL_EXIT,
 287 };
 288
 289 enum lttng_syscall_abi {
 290         LTTNG_SYSCALL_ABI_NATIVE,
 291         LTTNG_SYSCALL_ABI_COMPAT,
 292 };
 293
 294 /*
 295  * lttng_event structure is referred to by the tracing fast path. It must be
 296  * kept small.
 297  */
 298 struct lttng_event {
 299         enum lttng_event_type evtype;   /* First field. */
 300         unsigned int id;
 301         struct lttng_channel *chan;
 302         int enabled;
 303         const struct lttng_event_desc *desc;
 304         void *filter;
 305         struct lttng_ctx *ctx;
 306         enum lttng_kernel_instrumentation instrumentation;
 307         union {
 308                 struct lttng_kprobe kprobe;
 309                 struct {
 310                         struct lttng_krp *lttng_krp;
 311                         char *symbol_name;
 312                 } kretprobe;
 313                 struct {
 314                         struct inode *inode;
 315                         struct list_head head;
 316                 } uprobe;
 317                 struct {
 318                         char *syscall_name;
 319                         enum lttng_syscall_entryexit entryexit;
 320                         enum lttng_syscall_abi abi;
 321                 } syscall;
 322         } u;
 323         struct list_head list;          /* Event list in session */
 324         unsigned int metadata_dumped:1;
 325
 326         /* Backward references: list of lttng_enabler_ref (ref to enablers) */
 327         struct list_head enablers_ref_head;
 328         struct hlist_node hlist;        /* session ht of events */
 329         int registered;                 /* has reg'd tracepoint probe */
 330         /* list of struct lttng_bytecode_runtime, sorted by seqnum */
 331         struct list_head bytecode_runtime_head;
 332         int has_enablers_without_bytecode;
 333 };
 334
 335 // FIXME: Really similar to lttng_event above. Could those be merged ?
 336 struct lttng_event_notifier {
 337         enum lttng_event_type evtype;   /* First field. */
 338         uint64_t user_token;
 339         int enabled;
 340         int registered;                 /* has reg'd tracepoint probe */
 341         const struct lttng_event_desc *desc;
 342         void *filter;
 343         struct list_head list;          /* event_notifier list in event_notifier group */
 344
 345         enum lttng_kernel_instrumentation instrumentation;
 346         union {
 347                 struct lttng_kprobe kprobe;
 348         } u;
 349
 350         /* Backward references: list of lttng_enabler_ref (ref to enablers) */
 351         struct list_head enablers_ref_head;
 352         struct hlist_node hlist;        /* session ht of event_notifiers */
 353         /* list of struct lttng_bytecode_runtime, sorted by seqnum */
 354         struct list_head bytecode_runtime_head;
 355         int has_enablers_without_bytecode;
 356
 357         void (*send_notification)(struct lttng_event_notifier *event_notifier);
 358         struct lttng_event_notifier_group *group; /* Weak ref */
 359 };
 360
 361 enum lttng_enabler_format_type {
 362         LTTNG_ENABLER_FORMAT_STAR_GLOB,
 363         LTTNG_ENABLER_FORMAT_NAME,
 364 };
 365
 366 /*
 367  * Enabler field, within whatever object is enabling an event. Target of
 368  * backward reference.
 369  */
 370 struct lttng_enabler {
 371         enum lttng_event_type evtype;   /* First field. */
 372
 373         enum lttng_enabler_format_type format_type;
 374
 375         /* head list of struct lttng_ust_filter_bytecode_node */
 376         struct list_head filter_bytecode_head;
 377
 378         struct lttng_kernel_event event_param;
 379         unsigned int enabled:1;
 380
 381         uint64_t user_token;            /* User-provided token. */
 382 };
 383
 384 struct lttng_event_enabler {
 385         struct lttng_enabler base;
 386         struct list_head node;  /* per-session list of enablers */
 387         struct lttng_channel *chan;
 388         /*
 389          * Unused, but kept around to make it explicit that the tracer can do
 390          * it.
 391          */
 392         struct lttng_ctx *ctx;
 393 };
 394
 395 struct lttng_event_notifier_enabler {
 396         struct lttng_enabler base;
 397         struct list_head node;  /* List of event_notifier enablers */
 398         struct lttng_event_notifier_group *group;
 399 };
 400
 401 static inline
 402 struct lttng_enabler *lttng_event_enabler_as_enabler(
 403                 struct lttng_event_enabler *event_enabler)
 404 {
 405         return &event_enabler->base;
 406 }
 407
 408 static inline
 409 struct lttng_enabler *lttng_event_notifier_enabler_as_enabler(
 410                 struct lttng_event_notifier_enabler *event_notifier_enabler)
 411 {
 412         return &event_notifier_enabler->base;
 413 }
 414
 415 struct lttng_channel_ops {
 416         struct channel *(*channel_create)(const char *name,
 417                                 void *priv,
 418                                 void *buf_addr,
 419                                 size_t subbuf_size, size_t num_subbuf,
 420                                 unsigned int switch_timer_interval,
 421                                 unsigned int read_timer_interval);
 422         void (*channel_destroy)(struct channel *chan);
 423         struct lib_ring_buffer *(*buffer_read_open)(struct channel *chan);
 424         int (*buffer_has_read_closed_stream)(struct channel *chan);
 425         void (*buffer_read_close)(struct lib_ring_buffer *buf);
 426         int (*event_reserve)(struct lib_ring_buffer_ctx *ctx,
 427                              uint32_t event_id);
 428         void (*event_commit)(struct lib_ring_buffer_ctx *ctx);
 429         void (*event_write)(struct lib_ring_buffer_ctx *ctx, const void *src,
 430                             size_t len);
 431         void (*event_write_from_user)(struct lib_ring_buffer_ctx *ctx,
 432                                       const void *src, size_t len);
 433         void (*event_memset)(struct lib_ring_buffer_ctx *ctx,
 434                              int c, size_t len);
 435         void (*event_strcpy)(struct lib_ring_buffer_ctx *ctx, const char *src,
 436                              size_t len);
 437         void (*event_strcpy_from_user)(struct lib_ring_buffer_ctx *ctx,
 438                                        const char __user *src, size_t len);
 439         /*
 440          * packet_avail_size returns the available size in the current
 441          * packet. Note that the size returned is only a hint, since it
 442          * may change due to concurrent writes.
 443          */
 444         size_t (*packet_avail_size)(struct channel *chan);
 445         wait_queue_head_t *(*get_writer_buf_wait_queue)(struct channel *chan, int cpu);
 446         wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
 447         int (*is_finalized)(struct channel *chan);
 448         int (*is_disabled)(struct channel *chan);
 449         int (*timestamp_begin) (const struct lib_ring_buffer_config *config,
 450                         struct lib_ring_buffer *bufb,
 451                         uint64_t *timestamp_begin);
 452         int (*timestamp_end) (const struct lib_ring_buffer_config *config,
 453                         struct lib_ring_buffer *bufb,
 454                         uint64_t *timestamp_end);
 455         int (*events_discarded) (const struct lib_ring_buffer_config *config,
 456                         struct lib_ring_buffer *bufb,
 457                         uint64_t *events_discarded);
 458         int (*content_size) (const struct lib_ring_buffer_config *config,
 459                         struct lib_ring_buffer *bufb,
 460                         uint64_t *content_size);
 461         int (*packet_size) (const struct lib_ring_buffer_config *config,
 462                         struct lib_ring_buffer *bufb,
 463                         uint64_t *packet_size);
 464         int (*stream_id) (const struct lib_ring_buffer_config *config,
 465                         struct lib_ring_buffer *bufb,
 466                         uint64_t *stream_id);
 467         int (*current_timestamp) (const struct lib_ring_buffer_config *config,
 468                         struct lib_ring_buffer *bufb,
 469                         uint64_t *ts);
 470         int (*sequence_number) (const struct lib_ring_buffer_config *config,
 471                         struct lib_ring_buffer *bufb,
 472                         uint64_t *seq);
 473         int (*instance_id) (const struct lib_ring_buffer_config *config,
 474                         struct lib_ring_buffer *bufb,
 475                         uint64_t *id);
 476 };
 477
 478 struct lttng_transport {
 479         char *name;
 480         struct module *owner;
 481         struct list_head node;
 482         struct lttng_channel_ops ops;
 483 };
 484
 485 struct lttng_syscall_filter;
 486
 487 #define LTTNG_EVENT_HT_BITS             12
 488 #define LTTNG_EVENT_HT_SIZE             (1U << LTTNG_EVENT_HT_BITS)
 489
 490 struct lttng_event_ht {
 491         struct hlist_head table[LTTNG_EVENT_HT_SIZE];
 492 };
 493
 494 #define LTTNG_EVENT_NOTIFIER_HT_BITS            12
 495 #define LTTNG_EVENT_NOTIFIER_HT_SIZE            (1U << LTTNG_EVENT_NOTIFIER_HT_BITS)
 496
 497 struct lttng_event_notifier_ht {
 498         struct hlist_head table[LTTNG_EVENT_NOTIFIER_HT_SIZE];
 499 };
 500
 501 struct lttng_channel {
 502         unsigned int id;
 503         struct channel *chan;           /* Channel buffers */
 504         int enabled;
 505         struct lttng_ctx *ctx;
 506         /* Event ID management */
 507         struct lttng_session *session;
 508         struct file *file;              /* File associated to channel */
 509         unsigned int free_event_id;     /* Next event ID to allocate */
 510         struct list_head list;          /* Channel list */
 511         struct lttng_channel_ops *ops;
 512         struct lttng_transport *transport;
 513         struct lttng_event **sc_table;  /* for syscall tracing */
 514         struct lttng_event **compat_sc_table;
 515         struct lttng_event **sc_exit_table;     /* for syscall exit tracing */
 516         struct lttng_event **compat_sc_exit_table;
 517         struct lttng_event *sc_unknown; /* for unknown syscalls */
 518         struct lttng_event *sc_compat_unknown;
 519         struct lttng_event *sc_exit_unknown;
 520         struct lttng_event *compat_sc_exit_unknown;
 521         struct lttng_syscall_filter *sc_filter;
 522         int header_type;                /* 0: unset, 1: compact, 2: large */
 523         enum channel_type channel_type;
 524         int syscall_all;
 525         unsigned int metadata_dumped:1,
 526                 sys_enter_registered:1,
 527                 sys_exit_registered:1,
 528                 tstate:1;               /* Transient enable state */
 529 };
 530
 531 struct lttng_metadata_stream {
 532         void *priv;                     /* Ring buffer private data */
 533         struct lttng_metadata_cache *metadata_cache;
 534         unsigned int metadata_in;       /* Bytes read from the cache */
 535         unsigned int metadata_out;      /* Bytes consumed from stream */
 536         int finalized;                  /* Has channel been finalized */
 537         wait_queue_head_t read_wait;    /* Reader buffer-level wait queue */
 538         struct list_head list;          /* Stream list */
 539         struct lttng_transport *transport;
 540         uint64_t version;               /* Current version of the metadata cache */
 541         bool coherent;                  /* Stream in a coherent state */
 542 };
 543
 544 #define LTTNG_DYNAMIC_LEN_STACK_SIZE    128
 545
 546 struct lttng_dynamic_len_stack {
 547         size_t stack[LTTNG_DYNAMIC_LEN_STACK_SIZE];
 548         size_t offset;
 549 };
 550
 551 DECLARE_PER_CPU(struct lttng_dynamic_len_stack, lttng_dynamic_len_stack);
 552
 553 /*
 554  * struct lttng_id_tracker declared in header due to deferencing of *v
 555  * in RCU_INITIALIZER(v).
 556  */
 557 #define LTTNG_ID_HASH_BITS      6
 558 #define LTTNG_ID_TABLE_SIZE     (1 << LTTNG_ID_HASH_BITS)
 559
 560 enum tracker_type {
 561         TRACKER_PID,
 562         TRACKER_VPID,
 563         TRACKER_UID,
 564         TRACKER_VUID,
 565         TRACKER_GID,
 566         TRACKER_VGID,
 567
 568         TRACKER_UNKNOWN,
 569 };
 570
 571 struct lttng_id_tracker_rcu {
 572         struct hlist_head id_hash[LTTNG_ID_TABLE_SIZE];
 573 };
 574
 575 struct lttng_id_tracker {
 576         struct lttng_session *session;
 577         enum tracker_type tracker_type;
 578         struct lttng_id_tracker_rcu *p; /* RCU dereferenced. */
 579 };
 580
 581 struct lttng_id_hash_node {
 582         struct hlist_node hlist;
 583         int id;
 584 };
 585
 586 struct lttng_session {
 587         int active;                     /* Is trace session active ? */
 588         int been_active;                /* Has trace session been active ? */
 589         struct file *file;              /* File associated to session */
 590         struct list_head chan;          /* Channel list head */
 591         struct list_head events;        /* Event list head */
 592         struct list_head list;          /* Session list */
 593         unsigned int free_chan_id;      /* Next chan ID to allocate */
 594         uuid_le uuid;                   /* Trace session unique ID */
 595         struct lttng_metadata_cache *metadata_cache;
 596         struct lttng_id_tracker pid_tracker;
 597         struct lttng_id_tracker vpid_tracker;
 598         struct lttng_id_tracker uid_tracker;
 599         struct lttng_id_tracker vuid_tracker;
 600         struct lttng_id_tracker gid_tracker;
 601         struct lttng_id_tracker vgid_tracker;
 602         unsigned int metadata_dumped:1,
 603                 tstate:1;               /* Transient enable state */
 604         /* List of event enablers */
 605         struct list_head enablers_head;
 606         /* Hash table of events */
 607         struct lttng_event_ht events_ht;
 608         char name[LTTNG_KERNEL_SESSION_NAME_LEN];
 609         char creation_time[LTTNG_KERNEL_SESSION_CREATION_TIME_ISO8601_LEN];
 610 };
 611
 612 struct lttng_event_notifier_group {
 613         struct file *file;              /* File associated to event notifier group */
 614         struct file *notif_file;        /* File used to expose notifications to userspace. */
 615         struct list_head node;          /* event notifier group list */
 616         struct list_head enablers_head; /* List of enablers */
 617         struct list_head event_notifiers_head; /* List of event notifier */
 618         struct lttng_event_notifier_ht event_notifiers_ht; /* Hash table of event notifiers */
 619         struct lttng_ctx *ctx;          /* Contexts for filters. */
 620         struct lttng_channel_ops *ops;
 621         struct lttng_transport *transport;
 622         struct channel *chan;           /* Ring buffer channel for event notifier group. */
 623         struct lib_ring_buffer *buf;    /* Ring buffer for event notifier group. */
 624         wait_queue_head_t read_wait;
 625         struct irq_work wakeup_pending; /* Pending wakeup irq work. */
 626 };
 627
 628 struct lttng_metadata_cache {
 629         char *data;                     /* Metadata cache */
 630         unsigned int cache_alloc;       /* Metadata allocated size (bytes) */
 631         unsigned int metadata_written;  /* Number of bytes written in metadata cache */
 632         atomic_t producing;             /* Metadata being produced (incomplete) */
 633         struct kref refcount;           /* Metadata cache usage */
 634         struct list_head metadata_stream;       /* Metadata stream list */
 635         uuid_le uuid;                   /* Trace session unique ID (copy) */
 636         struct mutex lock;              /* Produce/consume lock */
 637         uint64_t version;               /* Current version of the metadata */
 638 };
 639
 640 void lttng_lock_sessions(void);
 641 void lttng_unlock_sessions(void);
 642
 643 struct list_head *lttng_get_probe_list_head(void);
 644
 645 struct lttng_event_enabler *lttng_event_enabler_create(
 646                 enum lttng_enabler_format_type format_type,
 647                 struct lttng_kernel_event *event_param,
 648                 struct lttng_channel *chan);
 649
 650 int lttng_event_enabler_enable(struct lttng_event_enabler *event_enabler);
 651 int lttng_event_enabler_disable(struct lttng_event_enabler *event_enabler);
 652 struct lttng_event_notifier_enabler *lttng_event_notifier_enabler_create(
 653                 struct lttng_event_notifier_group *event_notifier_group,
 654                 enum lttng_enabler_format_type format_type,
 655                 struct lttng_kernel_event_notifier *event_notifier_param);
 656
 657 int lttng_event_notifier_enabler_enable(
 658                 struct lttng_event_notifier_enabler *event_notifier_enabler);
 659 int lttng_event_notifier_enabler_disable(
 660                 struct lttng_event_notifier_enabler *event_notifier_enabler);
 661 int lttng_fix_pending_events(void);
 662 int lttng_fix_pending_event_notifiers(void);
 663 int lttng_session_active(void);
 664 bool lttng_event_notifier_active(void);
 665
 666 struct lttng_session *lttng_session_create(void);
 667 int lttng_session_enable(struct lttng_session *session);
 668 int lttng_session_disable(struct lttng_session *session);
 669 void lttng_session_destroy(struct lttng_session *session);
 670 int lttng_session_metadata_regenerate(struct lttng_session *session);
 671 int lttng_session_statedump(struct lttng_session *session);
 672 void metadata_cache_destroy(struct kref *kref);
 673
 674 struct lttng_event_notifier_group *lttng_event_notifier_group_create(void);
 675 void lttng_event_notifier_group_destroy(
 676                 struct lttng_event_notifier_group *event_notifier_group);
 677
 678 struct lttng_channel *lttng_channel_create(struct lttng_session *session,
 679                                        const char *transport_name,
 680                                        void *buf_addr,
 681                                        size_t subbuf_size, size_t num_subbuf,
 682                                        unsigned int switch_timer_interval,
 683                                        unsigned int read_timer_interval,
 684                                        enum channel_type channel_type);
 685 struct lttng_channel *lttng_global_channel_create(struct lttng_session *session,
 686                                        int overwrite, void *buf_addr,
 687                                        size_t subbuf_size, size_t num_subbuf,
 688                                        unsigned int switch_timer_interval,
 689                                        unsigned int read_timer_interval);
 690
 691 void lttng_metadata_channel_destroy(struct lttng_channel *chan);
 692 struct lttng_event *lttng_event_create(struct lttng_channel *chan,
 693                                 struct lttng_kernel_event *event_param,
 694                                 void *filter,
 695                                 const struct lttng_event_desc *event_desc,
 696                                 enum lttng_kernel_instrumentation itype);
 697 struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
 698                                 struct lttng_kernel_event *event_param,
 699                                 void *filter,
 700                                 const struct lttng_event_desc *event_desc,
 701                                 enum lttng_kernel_instrumentation itype);
 702 struct lttng_event *lttng_event_compat_old_create(struct lttng_channel *chan,
 703                 struct lttng_kernel_old_event *old_event_param,
 704                 void *filter,
 705                 const struct lttng_event_desc *internal_desc);
 706
 707 struct lttng_event_notifier *lttng_event_notifier_create(
 708                                 const struct lttng_event_desc *event_notifier_desc,
 709                                 uint64_t id,
 710                                 struct lttng_event_notifier_group *event_notifier_group,
 711                                 struct lttng_kernel_event_notifier *event_notifier_param,
 712                                 void *filter,
 713                                 enum lttng_kernel_instrumentation itype);
 714 struct lttng_event_notifier *_lttng_event_notifier_create(
 715                                 const struct lttng_event_desc *event_notifier_desc,
 716                                 uint64_t id,
 717                                 struct lttng_event_notifier_group *event_notifier_group,
 718                                 struct lttng_kernel_event_notifier *event_notifier_param,
 719                                 void *filter,
 720                                 enum lttng_kernel_instrumentation itype);
 721
 722 int lttng_channel_enable(struct lttng_channel *channel);
 723 int lttng_channel_disable(struct lttng_channel *channel);
 724 int lttng_event_enable(struct lttng_event *event);
 725 int lttng_event_disable(struct lttng_event *event);
 726
 727 int lttng_event_notifier_enable(struct lttng_event_notifier *event_notifier);
 728 int lttng_event_notifier_disable(struct lttng_event_notifier *event_notifier);
 729
 730 void lttng_transport_register(struct lttng_transport *transport);
 731 void lttng_transport_unregister(struct lttng_transport *transport);
 732
 733 void synchronize_trace(void);
 734 int lttng_abi_init(void);
 735 int lttng_abi_compat_old_init(void);
 736 void lttng_abi_exit(void);
 737 void lttng_abi_compat_old_exit(void);
 738
 739 int lttng_probe_register(struct lttng_probe_desc *desc);
 740 void lttng_probe_unregister(struct lttng_probe_desc *desc);
 741 const struct lttng_event_desc *lttng_event_desc_get(const char *name);
 742 void lttng_event_desc_put(const struct lttng_event_desc *desc);
 743 int lttng_probes_init(void);
 744 void lttng_probes_exit(void);
 745
 746 int lttng_metadata_output_channel(struct lttng_metadata_stream *stream,
 747                 struct channel *chan, bool *coherent);
 748
 749 int lttng_id_tracker_get_node_id(const struct lttng_id_hash_node *node);
 750 int lttng_id_tracker_empty_set(struct lttng_id_tracker *lf);
 751 void lttng_id_tracker_destroy(struct lttng_id_tracker *lf, bool rcu);
 752 bool lttng_id_tracker_lookup(struct lttng_id_tracker_rcu *p, int id);
 753 int lttng_id_tracker_add(struct lttng_id_tracker *lf, int id);
 754 int lttng_id_tracker_del(struct lttng_id_tracker *lf, int id);
 755
 756 int lttng_session_track_id(struct lttng_session *session,
 757                 enum tracker_type tracker_type, int id);
 758 int lttng_session_untrack_id(struct lttng_session *session,
 759                 enum tracker_type tracker_type, int id);
 760
 761 int lttng_session_list_tracker_ids(struct lttng_session *session,
 762                 enum tracker_type tracker_type);
 763
 764 void lttng_clock_ref(void);
 765 void lttng_clock_unref(void);
 766
 767 #if defined(CONFIG_HAVE_SYSCALL_TRACEPOINTS)
 768 int lttng_syscalls_register(struct lttng_channel *chan, void *filter);
 769 int lttng_syscalls_unregister(struct lttng_channel *chan);
 770 int lttng_syscalls_destroy(struct lttng_channel *chan);
 771 int lttng_syscall_filter_enable(struct lttng_channel *chan,
 772                 struct lttng_event *event);
 773 int lttng_syscall_filter_disable(struct lttng_channel *chan,
 774                 struct lttng_event *event);
 775 long lttng_channel_syscall_mask(struct lttng_channel *channel,
 776                 struct lttng_kernel_syscall_mask __user *usyscall_mask);
 777 #else
 778 static inline int lttng_syscalls_register(struct lttng_channel *chan, void *filter)
 779 {
 780         return -ENOSYS;
 781 }
 782
 783 static inline int lttng_syscalls_unregister(struct lttng_channel *chan)
 784 {
 785         return 0;
 786 }
 787
 788 static inline int lttng_syscalls_destroy(struct lttng_channel *chan)
 789 {
 790         return 0;
 791 }
 792
 793 static inline int lttng_syscall_filter_enable(struct lttng_channel *chan,
 794                 struct lttng_event *event);
 795 {
 796         return -ENOSYS;
 797 }
 798
 799 static inline int lttng_syscall_filter_disable(struct lttng_channel *chan,
 800                 struct lttng_event *event);
 801 {
 802         return -ENOSYS;
 803 }
 804
 805 static inline long lttng_channel_syscall_mask(struct lttng_channel *channel,
 806                 struct lttng_kernel_syscall_mask __user *usyscall_mask)
 807 {
 808         return -ENOSYS;
 809 }
 810
 811 #endif
 812
 813 void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime);
 814 int lttng_event_enabler_attach_bytecode(struct lttng_event_enabler *event_enabler,
 815                 struct lttng_kernel_filter_bytecode __user *bytecode);
 816 int lttng_event_notifier_enabler_attach_bytecode(
 817                 struct lttng_event_notifier_enabler *event_notifier_enabler,
 818                 struct lttng_kernel_filter_bytecode __user *bytecode);
 819
 820 void lttng_enabler_link_bytecode(const struct lttng_event_desc *event_desc,
 821                 struct lttng_ctx *ctx,
 822                 struct list_head *bytecode_runtime_head,
 823                 struct lttng_enabler *enabler);
 824
 825 int lttng_probes_init(void);
 826
 827 extern struct lttng_ctx *lttng_static_ctx;
 828
 829 int lttng_context_init(void);
 830 void lttng_context_exit(void);
 831 struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx);
 832 ssize_t lttng_append_context_index(struct lttng_ctx **ctx_p);
 833 struct lttng_ctx_field *lttng_get_context_field_from_index(struct lttng_ctx *ctx,
 834                 size_t index);
 835 void lttng_context_update(struct lttng_ctx *ctx);
 836 int lttng_find_context(struct lttng_ctx *ctx, const char *name);
 837 int lttng_get_context_index(struct lttng_ctx *ctx, const char *name);
 838 void lttng_remove_context_field(struct lttng_ctx **ctx,
 839                                 struct lttng_ctx_field *field);
 840 void lttng_remove_context_field_index(struct lttng_ctx **ctx_p, size_t index);
 841 void lttng_destroy_context(struct lttng_ctx *ctx);
 842 int lttng_add_pid_to_ctx(struct lttng_ctx **ctx);
 843 int lttng_add_cpu_id_to_ctx(struct lttng_ctx **ctx);
 844 int lttng_add_procname_to_ctx(struct lttng_ctx **ctx);
 845 int lttng_add_prio_to_ctx(struct lttng_ctx **ctx);
 846 int lttng_add_nice_to_ctx(struct lttng_ctx **ctx);
 847 int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
 848 int lttng_add_tid_to_ctx(struct lttng_ctx **ctx);
 849 int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
 850 int lttng_add_ppid_to_ctx(struct lttng_ctx **ctx);
 851 int lttng_add_vppid_to_ctx(struct lttng_ctx **ctx);
 852 int lttng_add_hostname_to_ctx(struct lttng_ctx **ctx);
 853 int lttng_add_interruptible_to_ctx(struct lttng_ctx **ctx);
 854 int lttng_add_need_reschedule_to_ctx(struct lttng_ctx **ctx);
 855 #if defined(CONFIG_PREEMPT_RT_FULL) || defined(CONFIG_PREEMPT)
 856 int lttng_add_preemptible_to_ctx(struct lttng_ctx **ctx);
 857 #else
 858 static inline
 859 int lttng_add_preemptible_to_ctx(struct lttng_ctx **ctx)
 860 {
 861         return -ENOSYS;
 862 }
 863 #endif
 864 #ifdef CONFIG_PREEMPT_RT_FULL
 865 int lttng_add_migratable_to_ctx(struct lttng_ctx **ctx);
 866 #else
 867 static inline
 868 int lttng_add_migratable_to_ctx(struct lttng_ctx **ctx)
 869 {
 870         return -ENOSYS;
 871 }
 872 #endif
 873
 874 int lttng_add_callstack_to_ctx(struct lttng_ctx **ctx, int type);
 875
 876 #if defined(CONFIG_CGROUPS) && \
 877         ((LINUX_VERSION_CODE >= KERNEL_VERSION(4,6,0)) || \
 878          LTTNG_UBUNTU_KERNEL_RANGE(4,4,0,0, 4,5,0,0))
 879 int lttng_add_cgroup_ns_to_ctx(struct lttng_ctx **ctx);
 880 #else
 881 static inline
 882 int lttng_add_cgroup_ns_to_ctx(struct lttng_ctx **ctx)
 883 {
 884         return -ENOSYS;
 885 }
 886 #endif
 887
 888 #if defined(CONFIG_IPC_NS) && \
 889         (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
 890 int lttng_add_ipc_ns_to_ctx(struct lttng_ctx **ctx);
 891 #else
 892 static inline
 893 int lttng_add_ipc_ns_to_ctx(struct lttng_ctx **ctx)
 894 {
 895         return -ENOSYS;
 896 }
 897 #endif
 898
 899 #if !defined(LTTNG_MNT_NS_MISSING_HEADER) && \
 900         (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
 901 int lttng_add_mnt_ns_to_ctx(struct lttng_ctx **ctx);
 902 #else
 903 static inline
 904 int lttng_add_mnt_ns_to_ctx(struct lttng_ctx **ctx)
 905 {
 906         return -ENOSYS;
 907 }
 908 #endif
 909
 910 #if defined(CONFIG_NET_NS) && \
 911         (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
 912 int lttng_add_net_ns_to_ctx(struct lttng_ctx **ctx);
 913 #else
 914 static inline
 915 int lttng_add_net_ns_to_ctx(struct lttng_ctx **ctx)
 916 {
 917         return -ENOSYS;
 918 }
 919 #endif
 920
 921 #if defined(CONFIG_PID_NS) && \
 922         (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
 923 int lttng_add_pid_ns_to_ctx(struct lttng_ctx **ctx);
 924 #else
 925 static inline
 926 int lttng_add_pid_ns_to_ctx(struct lttng_ctx **ctx)
 927 {
 928         return -ENOSYS;
 929 }
 930 #endif
 931
 932 #if defined(CONFIG_USER_NS) && \
 933         (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
 934 int lttng_add_user_ns_to_ctx(struct lttng_ctx **ctx);
 935 #else
 936 static inline
 937 int lttng_add_user_ns_to_ctx(struct lttng_ctx **ctx)
 938 {
 939         return -ENOSYS;
 940 }
 941 #endif
 942
 943 #if defined(CONFIG_UTS_NS) && \
 944         (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
 945 int lttng_add_uts_ns_to_ctx(struct lttng_ctx **ctx);
 946 #else
 947 static inline
 948 int lttng_add_uts_ns_to_ctx(struct lttng_ctx **ctx)
 949 {
 950         return -ENOSYS;
 951 }
 952 #endif
 953
 954 #if defined(CONFIG_TIME_NS) && \
 955         (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0))
 956 int lttng_add_time_ns_to_ctx(struct lttng_ctx **ctx);
 957 #else
 958 static inline
 959 int lttng_add_time_ns_to_ctx(struct lttng_ctx **ctx)
 960 {
 961         return -ENOSYS;
 962 }
 963 #endif
 964
 965 int lttng_add_uid_to_ctx(struct lttng_ctx **ctx);
 966 int lttng_add_euid_to_ctx(struct lttng_ctx **ctx);
 967 int lttng_add_suid_to_ctx(struct lttng_ctx **ctx);
 968 int lttng_add_gid_to_ctx(struct lttng_ctx **ctx);
 969 int lttng_add_egid_to_ctx(struct lttng_ctx **ctx);
 970 int lttng_add_sgid_to_ctx(struct lttng_ctx **ctx);
 971 int lttng_add_vuid_to_ctx(struct lttng_ctx **ctx);
 972 int lttng_add_veuid_to_ctx(struct lttng_ctx **ctx);
 973 int lttng_add_vsuid_to_ctx(struct lttng_ctx **ctx);
 974 int lttng_add_vgid_to_ctx(struct lttng_ctx **ctx);
 975 int lttng_add_vegid_to_ctx(struct lttng_ctx **ctx);
 976 int lttng_add_vsgid_to_ctx(struct lttng_ctx **ctx);
 977
 978 #if defined(CONFIG_PERF_EVENTS)
 979 int lttng_add_perf_counter_to_ctx(uint32_t type,
 980                                   uint64_t config,
 981                                   const char *name,
 982                                   struct lttng_ctx **ctx);
 983 int lttng_cpuhp_perf_counter_online(unsigned int cpu,
 984                 struct lttng_cpuhp_node *node);
 985 int lttng_cpuhp_perf_counter_dead(unsigned int cpu,
 986                 struct lttng_cpuhp_node *node);
 987 #else
 988 static inline
 989 int lttng_add_perf_counter_to_ctx(uint32_t type,
 990                                   uint64_t config,
 991                                   const char *name,
 992                                   struct lttng_ctx **ctx)
 993 {
 994         return -ENOSYS;
 995 }
 996 static inline
 997 int lttng_cpuhp_perf_counter_online(unsigned int cpu,
 998                 struct lttng_cpuhp_node *node)
 999 {
1000         return 0;
1001 }
1002 static inline
1003 int lttng_cpuhp_perf_counter_dead(unsigned int cpu,
1004                 struct lttng_cpuhp_node *node)
1005 {
1006         return 0;
1007 }
1008 #endif
1009
1010 int lttng_logger_init(void);
1011 void lttng_logger_exit(void);
1012
1013 extern int lttng_statedump_start(struct lttng_session *session);
1014
1015 #ifdef CONFIG_KPROBES
1016 int lttng_kprobes_register_event(const char *name,
1017                 const char *symbol_name,
1018                 uint64_t offset,
1019                 uint64_t addr,
1020                 struct lttng_event *event);
1021 void lttng_kprobes_unregister_event(struct lttng_event *event);
1022 void lttng_kprobes_destroy_event_private(struct lttng_event *event);
1023 int lttng_kprobes_register_event_notifier(const char *symbol_name,
1024                 uint64_t offset,
1025                 uint64_t addr,
1026                 struct lttng_event_notifier *event_notifier);
1027 void lttng_kprobes_unregister_event_notifier(struct lttng_event_notifier *event_notifier);
1028 void lttng_kprobes_destroy_event_notifier_private(struct lttng_event_notifier *event_notifier);
1029 #else
1030 static inline
1031 int lttng_kprobes_register_event(const char *name,
1032                 const char *symbol_name,
1033                 uint64_t offset,
1034                 uint64_t addr,
1035                 struct lttng_event *event)
1036 {
1037         return -ENOSYS;
1038 }
1039
1040 static inline
1041 void lttng_kprobes_unregister_event(struct lttng_event *event)
1042 {
1043 }
1044
1045 static inline
1046 void lttng_kprobes_destroy_event_private(struct lttng_event *event)
1047 {
1048 }
1049
1050 static inline
1051 int lttng_kprobes_register_event_notifier(const char *symbol_name,
1052                 uint64_t offset,
1053                 uint64_t addr,
1054                 struct lttng_event_notifier *event_notifier)
1055 {
1056         return -ENOSYS;
1057 }
1058
1059 static inline
1060 void lttng_kprobes_unregister_event_notifier(struct lttng_event_notifier *event_notifier)
1061 {
1062 }
1063
1064 static inline
1065 void lttng_kprobes_destroy_event_notifier_private(struct lttng_event_notifier *event_notifier)
1066 {
1067 }
1068 #endif
1069
1070 int lttng_event_add_callsite(struct lttng_event *event,
1071         struct lttng_kernel_event_callsite *callsite);
1072
1073 #ifdef CONFIG_UPROBES
1074 int lttng_uprobes_register(const char *name,
1075         int fd, struct lttng_event *event);
1076 int lttng_uprobes_add_callsite(struct lttng_event *event,
1077         struct lttng_kernel_event_callsite *callsite);
1078 void lttng_uprobes_unregister(struct lttng_event *event);
1079 void lttng_uprobes_destroy_private(struct lttng_event *event);
1080 #else
1081 static inline
1082 int lttng_uprobes_register(const char *name,
1083         int fd, struct lttng_event *event)
1084 {
1085         return -ENOSYS;
1086 }
1087
1088 static inline
1089 int lttng_uprobes_add_callsite(struct lttng_event *event,
1090         struct lttng_kernel_event_callsite *callsite)
1091 {
1092         return -ENOSYS;
1093 }
1094
1095 static inline
1096 void lttng_uprobes_unregister(struct lttng_event *event)
1097 {
1098 }
1099
1100 static inline
1101 void lttng_uprobes_destroy_private(struct lttng_event *event)
1102 {
1103 }
1104 #endif
1105
1106 #ifdef CONFIG_KRETPROBES
1107 int lttng_kretprobes_register(const char *name,
1108                 const char *symbol_name,
1109                 uint64_t offset,
1110                 uint64_t addr,
1111                 struct lttng_event *event_entry,
1112                 struct lttng_event *event_exit);
1113 void lttng_kretprobes_unregister(struct lttng_event *event);
1114 void lttng_kretprobes_destroy_private(struct lttng_event *event);
1115 int lttng_kretprobes_event_enable_state(struct lttng_event *event,
1116         int enable);
1117 #else
1118 static inline
1119 int lttng_kretprobes_register(const char *name,
1120                 const char *symbol_name,
1121                 uint64_t offset,
1122                 uint64_t addr,
1123                 struct lttng_event *event_entry,
1124                 struct lttng_event *event_exit)
1125 {
1126         return -ENOSYS;
1127 }
1128
1129 static inline
1130 void lttng_kretprobes_unregister(struct lttng_event *event)
1131 {
1132 }
1133
1134 static inline
1135 void lttng_kretprobes_destroy_private(struct lttng_event *event)
1136 {
1137 }
1138
1139 static inline
1140 int lttng_kretprobes_event_enable_state(struct lttng_event *event,
1141         int enable)
1142 {
1143         return -ENOSYS;
1144 }
1145 #endif
1146
1147 int lttng_calibrate(struct lttng_kernel_calibrate *calibrate);
1148
1149 extern const struct file_operations lttng_tracepoint_list_fops;
1150 extern const struct file_operations lttng_syscall_list_fops;
1151
1152 #define TRACEPOINT_HAS_DATA_ARG
1153
1154 static inline bool lttng_is_bytewise_integer(const struct lttng_type *type)
1155 {
1156         if (type->atype != atype_integer)
1157                 return false;
1158         switch (type->u.integer.size) {
1159         case 8:         /* Fall-through. */
1160         case 16:        /* Fall-through. */
1161         case 32:        /* Fall-through. */
1162         case 64:
1163                 break;
1164         default:
1165                 return false;
1166         }
1167         return true;
1168 }
1169
1170 #endif /* _LTTNG_EVENTS_H */