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 enum lttng_syscall_entryexit {
 280         LTTNG_SYSCALL_ENTRY,
 281         LTTNG_SYSCALL_EXIT,
 282 };
 283
 284 enum lttng_syscall_abi {
 285         LTTNG_SYSCALL_ABI_NATIVE,
 286         LTTNG_SYSCALL_ABI_COMPAT,
 287 };
 288
 289 /*
 290  * lttng_event structure is referred to by the tracing fast path. It must be
 291  * kept small.
 292  */
 293 struct lttng_event {
 294         enum lttng_event_type evtype;   /* First field. */
 295         unsigned int id;
 296         struct lttng_channel *chan;
 297         int enabled;
 298         const struct lttng_event_desc *desc;
 299         void *filter;
 300         struct lttng_ctx *ctx;
 301         enum lttng_kernel_instrumentation instrumentation;
 302         union {
 303                 struct {
 304                         struct kprobe kp;
 305                         char *symbol_name;
 306                 } kprobe;
 307                 struct {
 308                         struct lttng_krp *lttng_krp;
 309                         char *symbol_name;
 310                 } kretprobe;
 311                 struct {
 312                         struct inode *inode;
 313                         struct list_head head;
 314                 } uprobe;
 315                 struct {
 316                         char *syscall_name;
 317                         enum lttng_syscall_entryexit entryexit;
 318                         enum lttng_syscall_abi abi;
 319                 } syscall;
 320         } u;
 321         struct list_head list;          /* Event list in session */
 322         unsigned int metadata_dumped:1;
 323
 324         /* Backward references: list of lttng_enabler_ref (ref to enablers) */
 325         struct list_head enablers_ref_head;
 326         struct hlist_node hlist;        /* session ht of events */
 327         int registered;                 /* has reg'd tracepoint probe */
 328         /* list of struct lttng_bytecode_runtime, sorted by seqnum */
 329         struct list_head bytecode_runtime_head;
 330         int has_enablers_without_bytecode;
 331 };
 332
 333 // FIXME: Really similar to lttng_event above. Could those be merged ?
 334 struct lttng_event_notifier {
 335         enum lttng_event_type evtype;   /* First field. */
 336         uint64_t user_token;
 337         int enabled;
 338         int registered;                 /* has reg'd tracepoint probe */
 339         const struct lttng_event_desc *desc;
 340         void *filter;
 341         struct list_head list;          /* event_notifier list in event_notifier group */
 342
 343         enum lttng_kernel_instrumentation instrumentation;
 344         union {
 345         } u;
 346
 347         /* Backward references: list of lttng_enabler_ref (ref to enablers) */
 348         struct list_head enablers_ref_head;
 349         struct hlist_node hlist;        /* session ht of event_notifiers */
 350         /* list of struct lttng_bytecode_runtime, sorted by seqnum */
 351         struct list_head bytecode_runtime_head;
 352         int has_enablers_without_bytecode;
 353
 354         void (*send_notification)(struct lttng_event_notifier *event_notifier);
 355         struct lttng_event_notifier_group *group; /* Weak ref */
 356 };
 357
 358 enum lttng_enabler_format_type {
 359         LTTNG_ENABLER_FORMAT_STAR_GLOB,
 360         LTTNG_ENABLER_FORMAT_NAME,
 361 };
 362
 363 /*
 364  * Enabler field, within whatever object is enabling an event. Target of
 365  * backward reference.
 366  */
 367 struct lttng_enabler {
 368         enum lttng_event_type evtype;   /* First field. */
 369
 370         enum lttng_enabler_format_type format_type;
 371
 372         /* head list of struct lttng_ust_filter_bytecode_node */
 373         struct list_head filter_bytecode_head;
 374
 375         struct lttng_kernel_event event_param;
 376         unsigned int enabled:1;
 377
 378         uint64_t user_token;            /* User-provided token. */
 379 };
 380
 381 struct lttng_event_enabler {
 382         struct lttng_enabler base;
 383         struct list_head node;  /* per-session list of enablers */
 384         struct lttng_channel *chan;
 385         /*
 386          * Unused, but kept around to make it explicit that the tracer can do
 387          * it.
 388          */
 389         struct lttng_ctx *ctx;
 390 };
 391
 392 struct lttng_event_notifier_enabler {
 393         struct lttng_enabler base;
 394         struct list_head node;  /* List of event_notifier enablers */
 395         struct lttng_event_notifier_group *group;
 396 };
 397
 398 static inline
 399 struct lttng_enabler *lttng_event_enabler_as_enabler(
 400                 struct lttng_event_enabler *event_enabler)
 401 {
 402         return &event_enabler->base;
 403 }
 404
 405 static inline
 406 struct lttng_enabler *lttng_event_notifier_enabler_as_enabler(
 407                 struct lttng_event_notifier_enabler *event_notifier_enabler)
 408 {
 409         return &event_notifier_enabler->base;
 410 }
 411
 412 struct lttng_channel_ops {
 413         struct channel *(*channel_create)(const char *name,
 414                                 void *priv,
 415                                 void *buf_addr,
 416                                 size_t subbuf_size, size_t num_subbuf,
 417                                 unsigned int switch_timer_interval,
 418                                 unsigned int read_timer_interval);
 419         void (*channel_destroy)(struct channel *chan);
 420         struct lib_ring_buffer *(*buffer_read_open)(struct channel *chan);
 421         int (*buffer_has_read_closed_stream)(struct channel *chan);
 422         void (*buffer_read_close)(struct lib_ring_buffer *buf);
 423         int (*event_reserve)(struct lib_ring_buffer_ctx *ctx,
 424                              uint32_t event_id);
 425         void (*event_commit)(struct lib_ring_buffer_ctx *ctx);
 426         void (*event_write)(struct lib_ring_buffer_ctx *ctx, const void *src,
 427                             size_t len);
 428         void (*event_write_from_user)(struct lib_ring_buffer_ctx *ctx,
 429                                       const void *src, size_t len);
 430         void (*event_memset)(struct lib_ring_buffer_ctx *ctx,
 431                              int c, size_t len);
 432         void (*event_strcpy)(struct lib_ring_buffer_ctx *ctx, const char *src,
 433                              size_t len);
 434         void (*event_strcpy_from_user)(struct lib_ring_buffer_ctx *ctx,
 435                                        const char __user *src, size_t len);
 436         /*
 437          * packet_avail_size returns the available size in the current
 438          * packet. Note that the size returned is only a hint, since it
 439          * may change due to concurrent writes.
 440          */
 441         size_t (*packet_avail_size)(struct channel *chan);
 442         wait_queue_head_t *(*get_writer_buf_wait_queue)(struct channel *chan, int cpu);
 443         wait_queue_head_t *(*get_hp_wait_queue)(struct channel *chan);
 444         int (*is_finalized)(struct channel *chan);
 445         int (*is_disabled)(struct channel *chan);
 446         int (*timestamp_begin) (const struct lib_ring_buffer_config *config,
 447                         struct lib_ring_buffer *bufb,
 448                         uint64_t *timestamp_begin);
 449         int (*timestamp_end) (const struct lib_ring_buffer_config *config,
 450                         struct lib_ring_buffer *bufb,
 451                         uint64_t *timestamp_end);
 452         int (*events_discarded) (const struct lib_ring_buffer_config *config,
 453                         struct lib_ring_buffer *bufb,
 454                         uint64_t *events_discarded);
 455         int (*content_size) (const struct lib_ring_buffer_config *config,
 456                         struct lib_ring_buffer *bufb,
 457                         uint64_t *content_size);
 458         int (*packet_size) (const struct lib_ring_buffer_config *config,
 459                         struct lib_ring_buffer *bufb,
 460                         uint64_t *packet_size);
 461         int (*stream_id) (const struct lib_ring_buffer_config *config,
 462                         struct lib_ring_buffer *bufb,
 463                         uint64_t *stream_id);
 464         int (*current_timestamp) (const struct lib_ring_buffer_config *config,
 465                         struct lib_ring_buffer *bufb,
 466                         uint64_t *ts);
 467         int (*sequence_number) (const struct lib_ring_buffer_config *config,
 468                         struct lib_ring_buffer *bufb,
 469                         uint64_t *seq);
 470         int (*instance_id) (const struct lib_ring_buffer_config *config,
 471                         struct lib_ring_buffer *bufb,
 472                         uint64_t *id);
 473 };
 474
 475 struct lttng_transport {
 476         char *name;
 477         struct module *owner;
 478         struct list_head node;
 479         struct lttng_channel_ops ops;
 480 };
 481
 482 struct lttng_syscall_filter;
 483
 484 #define LTTNG_EVENT_HT_BITS             12
 485 #define LTTNG_EVENT_HT_SIZE             (1U << LTTNG_EVENT_HT_BITS)
 486
 487 struct lttng_event_ht {
 488         struct hlist_head table[LTTNG_EVENT_HT_SIZE];
 489 };
 490
 491 #define LTTNG_EVENT_NOTIFIER_HT_BITS            12
 492 #define LTTNG_EVENT_NOTIFIER_HT_SIZE            (1U << LTTNG_EVENT_NOTIFIER_HT_BITS)
 493
 494 struct lttng_event_notifier_ht {
 495         struct hlist_head table[LTTNG_EVENT_NOTIFIER_HT_SIZE];
 496 };
 497
 498 struct lttng_channel {
 499         unsigned int id;
 500         struct channel *chan;           /* Channel buffers */
 501         int enabled;
 502         struct lttng_ctx *ctx;
 503         /* Event ID management */
 504         struct lttng_session *session;
 505         struct file *file;              /* File associated to channel */
 506         unsigned int free_event_id;     /* Next event ID to allocate */
 507         struct list_head list;          /* Channel list */
 508         struct lttng_channel_ops *ops;
 509         struct lttng_transport *transport;
 510         struct lttng_event **sc_table;  /* for syscall tracing */
 511         struct lttng_event **compat_sc_table;
 512         struct lttng_event **sc_exit_table;     /* for syscall exit tracing */
 513         struct lttng_event **compat_sc_exit_table;
 514         struct lttng_event *sc_unknown; /* for unknown syscalls */
 515         struct lttng_event *sc_compat_unknown;
 516         struct lttng_event *sc_exit_unknown;
 517         struct lttng_event *compat_sc_exit_unknown;
 518         struct lttng_syscall_filter *sc_filter;
 519         int header_type;                /* 0: unset, 1: compact, 2: large */
 520         enum channel_type channel_type;
 521         int syscall_all;
 522         unsigned int metadata_dumped:1,
 523                 sys_enter_registered:1,
 524                 sys_exit_registered:1,
 525                 tstate:1;               /* Transient enable state */
 526 };
 527
 528 struct lttng_metadata_stream {
 529         void *priv;                     /* Ring buffer private data */
 530         struct lttng_metadata_cache *metadata_cache;
 531         unsigned int metadata_in;       /* Bytes read from the cache */
 532         unsigned int metadata_out;      /* Bytes consumed from stream */
 533         int finalized;                  /* Has channel been finalized */
 534         wait_queue_head_t read_wait;    /* Reader buffer-level wait queue */
 535         struct list_head list;          /* Stream list */
 536         struct lttng_transport *transport;
 537         uint64_t version;               /* Current version of the metadata cache */
 538         bool coherent;                  /* Stream in a coherent state */
 539 };
 540
 541 #define LTTNG_DYNAMIC_LEN_STACK_SIZE    128
 542
 543 struct lttng_dynamic_len_stack {
 544         size_t stack[LTTNG_DYNAMIC_LEN_STACK_SIZE];
 545         size_t offset;
 546 };
 547
 548 DECLARE_PER_CPU(struct lttng_dynamic_len_stack, lttng_dynamic_len_stack);
 549
 550 /*
 551  * struct lttng_id_tracker declared in header due to deferencing of *v
 552  * in RCU_INITIALIZER(v).
 553  */
 554 #define LTTNG_ID_HASH_BITS      6
 555 #define LTTNG_ID_TABLE_SIZE     (1 << LTTNG_ID_HASH_BITS)
 556
 557 enum tracker_type {
 558         TRACKER_PID,
 559         TRACKER_VPID,
 560         TRACKER_UID,
 561         TRACKER_VUID,
 562         TRACKER_GID,
 563         TRACKER_VGID,
 564
 565         TRACKER_UNKNOWN,
 566 };
 567
 568 struct lttng_id_tracker_rcu {
 569         struct hlist_head id_hash[LTTNG_ID_TABLE_SIZE];
 570 };
 571
 572 struct lttng_id_tracker {
 573         struct lttng_session *session;
 574         enum tracker_type tracker_type;
 575         struct lttng_id_tracker_rcu *p; /* RCU dereferenced. */
 576 };
 577
 578 struct lttng_id_hash_node {
 579         struct hlist_node hlist;
 580         int id;
 581 };
 582
 583 struct lttng_session {
 584         int active;                     /* Is trace session active ? */
 585         int been_active;                /* Has trace session been active ? */
 586         struct file *file;              /* File associated to session */
 587         struct list_head chan;          /* Channel list head */
 588         struct list_head events;        /* Event list head */
 589         struct list_head list;          /* Session list */
 590         unsigned int free_chan_id;      /* Next chan ID to allocate */
 591         uuid_le uuid;                   /* Trace session unique ID */
 592         struct lttng_metadata_cache *metadata_cache;
 593         struct lttng_id_tracker pid_tracker;
 594         struct lttng_id_tracker vpid_tracker;
 595         struct lttng_id_tracker uid_tracker;
 596         struct lttng_id_tracker vuid_tracker;
 597         struct lttng_id_tracker gid_tracker;
 598         struct lttng_id_tracker vgid_tracker;
 599         unsigned int metadata_dumped:1,
 600                 tstate:1;               /* Transient enable state */
 601         /* List of event enablers */
 602         struct list_head enablers_head;
 603         /* Hash table of events */
 604         struct lttng_event_ht events_ht;
 605         char name[LTTNG_KERNEL_SESSION_NAME_LEN];
 606         char creation_time[LTTNG_KERNEL_SESSION_CREATION_TIME_ISO8601_LEN];
 607 };
 608
 609 struct lttng_event_notifier_group {
 610         struct file *file;              /* File associated to event notifier group */
 611         struct file *notif_file;        /* File used to expose notifications to userspace. */
 612         struct list_head node;          /* event notifier group list */
 613         struct list_head enablers_head; /* List of enablers */
 614         struct list_head event_notifiers_head; /* List of event notifier */
 615         struct lttng_event_notifier_ht event_notifiers_ht; /* Hash table of event notifiers */
 616         struct lttng_ctx *ctx;          /* Contexts for filters. */
 617         struct lttng_channel_ops *ops;
 618         struct lttng_transport *transport;
 619         struct channel *chan;           /* Ring buffer channel for event notifier group. */
 620         struct lib_ring_buffer *buf;    /* Ring buffer for event notifier group. */
 621         wait_queue_head_t read_wait;
 622         struct irq_work wakeup_pending; /* Pending wakeup irq work. */
 623 };
 624
 625 struct lttng_metadata_cache {
 626         char *data;                     /* Metadata cache */
 627         unsigned int cache_alloc;       /* Metadata allocated size (bytes) */
 628         unsigned int metadata_written;  /* Number of bytes written in metadata cache */
 629         atomic_t producing;             /* Metadata being produced (incomplete) */
 630         struct kref refcount;           /* Metadata cache usage */
 631         struct list_head metadata_stream;       /* Metadata stream list */
 632         uuid_le uuid;                   /* Trace session unique ID (copy) */
 633         struct mutex lock;              /* Produce/consume lock */
 634         uint64_t version;               /* Current version of the metadata */
 635 };
 636
 637 void lttng_lock_sessions(void);
 638 void lttng_unlock_sessions(void);
 639
 640 struct list_head *lttng_get_probe_list_head(void);
 641
 642 struct lttng_event_enabler *lttng_event_enabler_create(
 643                 enum lttng_enabler_format_type format_type,
 644                 struct lttng_kernel_event *event_param,
 645                 struct lttng_channel *chan);
 646
 647 int lttng_event_enabler_enable(struct lttng_event_enabler *event_enabler);
 648 int lttng_event_enabler_disable(struct lttng_event_enabler *event_enabler);
 649 struct lttng_event_notifier_enabler *lttng_event_notifier_enabler_create(
 650                 struct lttng_event_notifier_group *event_notifier_group,
 651                 enum lttng_enabler_format_type format_type,
 652                 struct lttng_kernel_event_notifier *event_notifier_param);
 653
 654 int lttng_event_notifier_enabler_enable(
 655                 struct lttng_event_notifier_enabler *event_notifier_enabler);
 656 int lttng_event_notifier_enabler_disable(
 657                 struct lttng_event_notifier_enabler *event_notifier_enabler);
 658 int lttng_fix_pending_events(void);
 659 int lttng_fix_pending_event_notifiers(void);
 660 int lttng_session_active(void);
 661 bool lttng_event_notifier_active(void);
 662
 663 struct lttng_session *lttng_session_create(void);
 664 int lttng_session_enable(struct lttng_session *session);
 665 int lttng_session_disable(struct lttng_session *session);
 666 void lttng_session_destroy(struct lttng_session *session);
 667 int lttng_session_metadata_regenerate(struct lttng_session *session);
 668 int lttng_session_statedump(struct lttng_session *session);
 669 void metadata_cache_destroy(struct kref *kref);
 670
 671 struct lttng_event_notifier_group *lttng_event_notifier_group_create(void);
 672 void lttng_event_notifier_group_destroy(
 673                 struct lttng_event_notifier_group *event_notifier_group);
 674
 675 struct lttng_channel *lttng_channel_create(struct lttng_session *session,
 676                                        const char *transport_name,
 677                                        void *buf_addr,
 678                                        size_t subbuf_size, size_t num_subbuf,
 679                                        unsigned int switch_timer_interval,
 680                                        unsigned int read_timer_interval,
 681                                        enum channel_type channel_type);
 682 struct lttng_channel *lttng_global_channel_create(struct lttng_session *session,
 683                                        int overwrite, void *buf_addr,
 684                                        size_t subbuf_size, size_t num_subbuf,
 685                                        unsigned int switch_timer_interval,
 686                                        unsigned int read_timer_interval);
 687
 688 void lttng_metadata_channel_destroy(struct lttng_channel *chan);
 689 struct lttng_event *lttng_event_create(struct lttng_channel *chan,
 690                                 struct lttng_kernel_event *event_param,
 691                                 void *filter,
 692                                 const struct lttng_event_desc *event_desc,
 693                                 enum lttng_kernel_instrumentation itype);
 694 struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
 695                                 struct lttng_kernel_event *event_param,
 696                                 void *filter,
 697                                 const struct lttng_event_desc *event_desc,
 698                                 enum lttng_kernel_instrumentation itype);
 699 struct lttng_event *lttng_event_compat_old_create(struct lttng_channel *chan,
 700                 struct lttng_kernel_old_event *old_event_param,
 701                 void *filter,
 702                 const struct lttng_event_desc *internal_desc);
 703
 704 struct lttng_event_notifier *lttng_event_notifier_create(
 705                                 const struct lttng_event_desc *event_notifier_desc,
 706                                 uint64_t id,
 707                                 struct lttng_event_notifier_group *event_notifier_group,
 708                                 struct lttng_kernel_event_notifier *event_notifier_param,
 709                                 void *filter,
 710                                 enum lttng_kernel_instrumentation itype);
 711 struct lttng_event_notifier *_lttng_event_notifier_create(
 712                                 const struct lttng_event_desc *event_notifier_desc,
 713                                 uint64_t id,
 714                                 struct lttng_event_notifier_group *event_notifier_group,
 715                                 struct lttng_kernel_event_notifier *event_notifier_param,
 716                                 void *filter,
 717                                 enum lttng_kernel_instrumentation itype);
 718
 719 int lttng_channel_enable(struct lttng_channel *channel);
 720 int lttng_channel_disable(struct lttng_channel *channel);
 721 int lttng_event_enable(struct lttng_event *event);
 722 int lttng_event_disable(struct lttng_event *event);
 723
 724 void lttng_transport_register(struct lttng_transport *transport);
 725 void lttng_transport_unregister(struct lttng_transport *transport);
 726
 727 void synchronize_trace(void);
 728 int lttng_abi_init(void);
 729 int lttng_abi_compat_old_init(void);
 730 void lttng_abi_exit(void);
 731 void lttng_abi_compat_old_exit(void);
 732
 733 int lttng_probe_register(struct lttng_probe_desc *desc);
 734 void lttng_probe_unregister(struct lttng_probe_desc *desc);
 735 const struct lttng_event_desc *lttng_event_desc_get(const char *name);
 736 void lttng_event_desc_put(const struct lttng_event_desc *desc);
 737 int lttng_probes_init(void);
 738 void lttng_probes_exit(void);
 739
 740 int lttng_metadata_output_channel(struct lttng_metadata_stream *stream,
 741                 struct channel *chan, bool *coherent);
 742
 743 int lttng_id_tracker_get_node_id(const struct lttng_id_hash_node *node);
 744 int lttng_id_tracker_empty_set(struct lttng_id_tracker *lf);
 745 void lttng_id_tracker_destroy(struct lttng_id_tracker *lf, bool rcu);
 746 bool lttng_id_tracker_lookup(struct lttng_id_tracker_rcu *p, int id);
 747 int lttng_id_tracker_add(struct lttng_id_tracker *lf, int id);
 748 int lttng_id_tracker_del(struct lttng_id_tracker *lf, int id);
 749
 750 int lttng_session_track_id(struct lttng_session *session,
 751                 enum tracker_type tracker_type, int id);
 752 int lttng_session_untrack_id(struct lttng_session *session,
 753                 enum tracker_type tracker_type, int id);
 754
 755 int lttng_session_list_tracker_ids(struct lttng_session *session,
 756                 enum tracker_type tracker_type);
 757
 758 void lttng_clock_ref(void);
 759 void lttng_clock_unref(void);
 760
 761 #if defined(CONFIG_HAVE_SYSCALL_TRACEPOINTS)
 762 int lttng_syscalls_register(struct lttng_channel *chan, void *filter);
 763 int lttng_syscalls_unregister(struct lttng_channel *chan);
 764 int lttng_syscalls_destroy(struct lttng_channel *chan);
 765 int lttng_syscall_filter_enable(struct lttng_channel *chan,
 766                 struct lttng_event *event);
 767 int lttng_syscall_filter_disable(struct lttng_channel *chan,
 768                 struct lttng_event *event);
 769 long lttng_channel_syscall_mask(struct lttng_channel *channel,
 770                 struct lttng_kernel_syscall_mask __user *usyscall_mask);
 771 #else
 772 static inline int lttng_syscalls_register(struct lttng_channel *chan, void *filter)
 773 {
 774         return -ENOSYS;
 775 }
 776
 777 static inline int lttng_syscalls_unregister(struct lttng_channel *chan)
 778 {
 779         return 0;
 780 }
 781
 782 static inline int lttng_syscalls_destroy(struct lttng_channel *chan)
 783 {
 784         return 0;
 785 }
 786
 787 static inline int lttng_syscall_filter_enable(struct lttng_channel *chan,
 788                 struct lttng_event *event);
 789 {
 790         return -ENOSYS;
 791 }
 792
 793 static inline int lttng_syscall_filter_disable(struct lttng_channel *chan,
 794                 struct lttng_event *event);
 795 {
 796         return -ENOSYS;
 797 }
 798
 799 static inline long lttng_channel_syscall_mask(struct lttng_channel *channel,
 800                 struct lttng_kernel_syscall_mask __user *usyscall_mask)
 801 {
 802         return -ENOSYS;
 803 }
 804
 805 #endif
 806
 807 void lttng_filter_sync_state(struct lttng_bytecode_runtime *runtime);
 808 int lttng_event_enabler_attach_bytecode(struct lttng_event_enabler *event_enabler,
 809                 struct lttng_kernel_filter_bytecode __user *bytecode);
 810 int lttng_event_notifier_enabler_attach_bytecode(
 811                 struct lttng_event_notifier_enabler *event_notifier_enabler,
 812                 struct lttng_kernel_filter_bytecode __user *bytecode);
 813
 814 void lttng_enabler_link_bytecode(const struct lttng_event_desc *event_desc,
 815                 struct lttng_ctx *ctx,
 816                 struct list_head *bytecode_runtime_head,
 817                 struct lttng_enabler *enabler);
 818
 819 int lttng_probes_init(void);
 820
 821 extern struct lttng_ctx *lttng_static_ctx;
 822
 823 int lttng_context_init(void);
 824 void lttng_context_exit(void);
 825 struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx);
 826 ssize_t lttng_append_context_index(struct lttng_ctx **ctx_p);
 827 struct lttng_ctx_field *lttng_get_context_field_from_index(struct lttng_ctx *ctx,
 828                 size_t index);
 829 void lttng_context_update(struct lttng_ctx *ctx);
 830 int lttng_find_context(struct lttng_ctx *ctx, const char *name);
 831 int lttng_get_context_index(struct lttng_ctx *ctx, const char *name);
 832 void lttng_remove_context_field(struct lttng_ctx **ctx,
 833                                 struct lttng_ctx_field *field);
 834 void lttng_remove_context_field_index(struct lttng_ctx **ctx_p, size_t index);
 835 void lttng_destroy_context(struct lttng_ctx *ctx);
 836 int lttng_add_pid_to_ctx(struct lttng_ctx **ctx);
 837 int lttng_add_cpu_id_to_ctx(struct lttng_ctx **ctx);
 838 int lttng_add_procname_to_ctx(struct lttng_ctx **ctx);
 839 int lttng_add_prio_to_ctx(struct lttng_ctx **ctx);
 840 int lttng_add_nice_to_ctx(struct lttng_ctx **ctx);
 841 int lttng_add_vpid_to_ctx(struct lttng_ctx **ctx);
 842 int lttng_add_tid_to_ctx(struct lttng_ctx **ctx);
 843 int lttng_add_vtid_to_ctx(struct lttng_ctx **ctx);
 844 int lttng_add_ppid_to_ctx(struct lttng_ctx **ctx);
 845 int lttng_add_vppid_to_ctx(struct lttng_ctx **ctx);
 846 int lttng_add_hostname_to_ctx(struct lttng_ctx **ctx);
 847 int lttng_add_interruptible_to_ctx(struct lttng_ctx **ctx);
 848 int lttng_add_need_reschedule_to_ctx(struct lttng_ctx **ctx);
 849 #if defined(CONFIG_PREEMPT_RT_FULL) || defined(CONFIG_PREEMPT)
 850 int lttng_add_preemptible_to_ctx(struct lttng_ctx **ctx);
 851 #else
 852 static inline
 853 int lttng_add_preemptible_to_ctx(struct lttng_ctx **ctx)
 854 {
 855         return -ENOSYS;
 856 }
 857 #endif
 858 #ifdef CONFIG_PREEMPT_RT_FULL
 859 int lttng_add_migratable_to_ctx(struct lttng_ctx **ctx);
 860 #else
 861 static inline
 862 int lttng_add_migratable_to_ctx(struct lttng_ctx **ctx)
 863 {
 864         return -ENOSYS;
 865 }
 866 #endif
 867
 868 int lttng_add_callstack_to_ctx(struct lttng_ctx **ctx, int type);
 869
 870 #if defined(CONFIG_CGROUPS) && \
 871         ((LINUX_VERSION_CODE >= KERNEL_VERSION(4,6,0)) || \
 872          LTTNG_UBUNTU_KERNEL_RANGE(4,4,0,0, 4,5,0,0))
 873 int lttng_add_cgroup_ns_to_ctx(struct lttng_ctx **ctx);
 874 #else
 875 static inline
 876 int lttng_add_cgroup_ns_to_ctx(struct lttng_ctx **ctx)
 877 {
 878         return -ENOSYS;
 879 }
 880 #endif
 881
 882 #if defined(CONFIG_IPC_NS) && \
 883         (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
 884 int lttng_add_ipc_ns_to_ctx(struct lttng_ctx **ctx);
 885 #else
 886 static inline
 887 int lttng_add_ipc_ns_to_ctx(struct lttng_ctx **ctx)
 888 {
 889         return -ENOSYS;
 890 }
 891 #endif
 892
 893 #if !defined(LTTNG_MNT_NS_MISSING_HEADER) && \
 894         (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
 895 int lttng_add_mnt_ns_to_ctx(struct lttng_ctx **ctx);
 896 #else
 897 static inline
 898 int lttng_add_mnt_ns_to_ctx(struct lttng_ctx **ctx)
 899 {
 900         return -ENOSYS;
 901 }
 902 #endif
 903
 904 #if defined(CONFIG_NET_NS) && \
 905         (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
 906 int lttng_add_net_ns_to_ctx(struct lttng_ctx **ctx);
 907 #else
 908 static inline
 909 int lttng_add_net_ns_to_ctx(struct lttng_ctx **ctx)
 910 {
 911         return -ENOSYS;
 912 }
 913 #endif
 914
 915 #if defined(CONFIG_PID_NS) && \
 916         (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
 917 int lttng_add_pid_ns_to_ctx(struct lttng_ctx **ctx);
 918 #else
 919 static inline
 920 int lttng_add_pid_ns_to_ctx(struct lttng_ctx **ctx)
 921 {
 922         return -ENOSYS;
 923 }
 924 #endif
 925
 926 #if defined(CONFIG_USER_NS) && \
 927         (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
 928 int lttng_add_user_ns_to_ctx(struct lttng_ctx **ctx);
 929 #else
 930 static inline
 931 int lttng_add_user_ns_to_ctx(struct lttng_ctx **ctx)
 932 {
 933         return -ENOSYS;
 934 }
 935 #endif
 936
 937 #if defined(CONFIG_UTS_NS) && \
 938         (LINUX_VERSION_CODE >= KERNEL_VERSION(3,8,0))
 939 int lttng_add_uts_ns_to_ctx(struct lttng_ctx **ctx);
 940 #else
 941 static inline
 942 int lttng_add_uts_ns_to_ctx(struct lttng_ctx **ctx)
 943 {
 944         return -ENOSYS;
 945 }
 946 #endif
 947
 948 #if defined(CONFIG_TIME_NS) && \
 949         (LINUX_VERSION_CODE >= KERNEL_VERSION(5,6,0))
 950 int lttng_add_time_ns_to_ctx(struct lttng_ctx **ctx);
 951 #else
 952 static inline
 953 int lttng_add_time_ns_to_ctx(struct lttng_ctx **ctx)
 954 {
 955         return -ENOSYS;
 956 }
 957 #endif
 958
 959 int lttng_add_uid_to_ctx(struct lttng_ctx **ctx);
 960 int lttng_add_euid_to_ctx(struct lttng_ctx **ctx);
 961 int lttng_add_suid_to_ctx(struct lttng_ctx **ctx);
 962 int lttng_add_gid_to_ctx(struct lttng_ctx **ctx);
 963 int lttng_add_egid_to_ctx(struct lttng_ctx **ctx);
 964 int lttng_add_sgid_to_ctx(struct lttng_ctx **ctx);
 965 int lttng_add_vuid_to_ctx(struct lttng_ctx **ctx);
 966 int lttng_add_veuid_to_ctx(struct lttng_ctx **ctx);
 967 int lttng_add_vsuid_to_ctx(struct lttng_ctx **ctx);
 968 int lttng_add_vgid_to_ctx(struct lttng_ctx **ctx);
 969 int lttng_add_vegid_to_ctx(struct lttng_ctx **ctx);
 970 int lttng_add_vsgid_to_ctx(struct lttng_ctx **ctx);
 971
 972 #if defined(CONFIG_PERF_EVENTS)
 973 int lttng_add_perf_counter_to_ctx(uint32_t type,
 974                                   uint64_t config,
 975                                   const char *name,
 976                                   struct lttng_ctx **ctx);
 977 int lttng_cpuhp_perf_counter_online(unsigned int cpu,
 978                 struct lttng_cpuhp_node *node);
 979 int lttng_cpuhp_perf_counter_dead(unsigned int cpu,
 980                 struct lttng_cpuhp_node *node);
 981 #else
 982 static inline
 983 int lttng_add_perf_counter_to_ctx(uint32_t type,
 984                                   uint64_t config,
 985                                   const char *name,
 986                                   struct lttng_ctx **ctx)
 987 {
 988         return -ENOSYS;
 989 }
 990 static inline
 991 int lttng_cpuhp_perf_counter_online(unsigned int cpu,
 992                 struct lttng_cpuhp_node *node)
 993 {
 994         return 0;
 995 }
 996 static inline
 997 int lttng_cpuhp_perf_counter_dead(unsigned int cpu,
 998                 struct lttng_cpuhp_node *node)
 999 {
1000         return 0;
1001 }
1002 #endif
1003
1004 int lttng_logger_init(void);
1005 void lttng_logger_exit(void);
1006
1007 extern int lttng_statedump_start(struct lttng_session *session);
1008
1009 #ifdef CONFIG_KPROBES
1010 int lttng_kprobes_register(const char *name,
1011                 const char *symbol_name,
1012                 uint64_t offset,
1013                 uint64_t addr,
1014                 struct lttng_event *event);
1015 void lttng_kprobes_unregister(struct lttng_event *event);
1016 void lttng_kprobes_destroy_private(struct lttng_event *event);
1017 #else
1018 static inline
1019 int lttng_kprobes_register(const char *name,
1020                 const char *symbol_name,
1021                 uint64_t offset,
1022                 uint64_t addr,
1023                 struct lttng_event *event)
1024 {
1025         return -ENOSYS;
1026 }
1027
1028 static inline
1029 void lttng_kprobes_unregister(struct lttng_event *event)
1030 {
1031 }
1032
1033 static inline
1034 void lttng_kprobes_destroy_private(struct lttng_event *event)
1035 {
1036 }
1037 #endif
1038
1039 int lttng_event_add_callsite(struct lttng_event *event,
1040         struct lttng_kernel_event_callsite *callsite);
1041
1042 #ifdef CONFIG_UPROBES
1043 int lttng_uprobes_register(const char *name,
1044         int fd, struct lttng_event *event);
1045 int lttng_uprobes_add_callsite(struct lttng_event *event,
1046         struct lttng_kernel_event_callsite *callsite);
1047 void lttng_uprobes_unregister(struct lttng_event *event);
1048 void lttng_uprobes_destroy_private(struct lttng_event *event);
1049 #else
1050 static inline
1051 int lttng_uprobes_register(const char *name,
1052         int fd, struct lttng_event *event)
1053 {
1054         return -ENOSYS;
1055 }
1056
1057 static inline
1058 int lttng_uprobes_add_callsite(struct lttng_event *event,
1059         struct lttng_kernel_event_callsite *callsite)
1060 {
1061         return -ENOSYS;
1062 }
1063
1064 static inline
1065 void lttng_uprobes_unregister(struct lttng_event *event)
1066 {
1067 }
1068
1069 static inline
1070 void lttng_uprobes_destroy_private(struct lttng_event *event)
1071 {
1072 }
1073 #endif
1074
1075 #ifdef CONFIG_KRETPROBES
1076 int lttng_kretprobes_register(const char *name,
1077                 const char *symbol_name,
1078                 uint64_t offset,
1079                 uint64_t addr,
1080                 struct lttng_event *event_entry,
1081                 struct lttng_event *event_exit);
1082 void lttng_kretprobes_unregister(struct lttng_event *event);
1083 void lttng_kretprobes_destroy_private(struct lttng_event *event);
1084 int lttng_kretprobes_event_enable_state(struct lttng_event *event,
1085         int enable);
1086 #else
1087 static inline
1088 int lttng_kretprobes_register(const char *name,
1089                 const char *symbol_name,
1090                 uint64_t offset,
1091                 uint64_t addr,
1092                 struct lttng_event *event_entry,
1093                 struct lttng_event *event_exit)
1094 {
1095         return -ENOSYS;
1096 }
1097
1098 static inline
1099 void lttng_kretprobes_unregister(struct lttng_event *event)
1100 {
1101 }
1102
1103 static inline
1104 void lttng_kretprobes_destroy_private(struct lttng_event *event)
1105 {
1106 }
1107
1108 static inline
1109 int lttng_kretprobes_event_enable_state(struct lttng_event *event,
1110         int enable)
1111 {
1112         return -ENOSYS;
1113 }
1114 #endif
1115
1116 int lttng_calibrate(struct lttng_kernel_calibrate *calibrate);
1117
1118 extern const struct file_operations lttng_tracepoint_list_fops;
1119 extern const struct file_operations lttng_syscall_list_fops;
1120
1121 #define TRACEPOINT_HAS_DATA_ARG
1122
1123 static inline bool lttng_is_bytewise_integer(const struct lttng_type *type)
1124 {
1125         if (type->atype != atype_integer)
1126                 return false;
1127         switch (type->u.integer.size) {
1128         case 8:         /* Fall-through. */
1129         case 16:        /* Fall-through. */
1130         case 32:        /* Fall-through. */
1131         case 64:
1132                 break;
1133         default:
1134                 return false;
1135         }
1136         return true;
1137 }
1138
1139 #endif /* _LTTNG_EVENTS_H */