libust/tracer.h

   1 /*
   2  * Copyright (C) 2005,2006,2008 Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
   3  * Copyright (C) 2009 Pierre-Marc Fournier
   4  *
   5  * This contains the definitions for the Linux Trace Toolkit tracer.
   6  *
   7  * Ported to userspace by Pierre-Marc Fournier.
   8  *
   9  * This library is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public
  11  * License as published by the Free Software Foundation; either
  12  * version 2.1 of the License, or (at your option) any later version.
  13  *
  14  * This library is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * Lesser General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU Lesser General Public
  20  * License along with this library; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
  22  */
  23
  24 #ifndef _LTT_TRACER_H
  25 #define _LTT_TRACER_H
  26
  27 #include <sys/types.h>
  28 #include <stdarg.h>
  29 //#include "list.h"
  30 #include <ust/kernelcompat.h>
  31 #include "buffers.h"
  32 #include "channels.h"
  33 #include "tracercore.h"
  34 #include <ust/marker.h>
  35
  36 /* Number of bytes to log with a read/write event */
  37 #define LTT_LOG_RW_SIZE                 32L
  38
  39 /* Interval (in jiffies) at which the LTT per-CPU timer fires */
  40 #define LTT_PERCPU_TIMER_INTERVAL       1
  41
  42 #ifndef LTT_ARCH_TYPE
  43 #define LTT_ARCH_TYPE                   LTT_ARCH_TYPE_UNDEFINED
  44 #endif
  45
  46 #ifndef LTT_ARCH_VARIANT
  47 #define LTT_ARCH_VARIANT                LTT_ARCH_VARIANT_NONE
  48 #endif
  49
  50 struct ltt_active_marker;
  51
  52 /* Maximum number of callbacks per marker */
  53 #define LTT_NR_CALLBACKS        10
  54
  55 struct ltt_serialize_closure;
  56 struct ltt_probe_private_data;
  57
  58 /* Serialization callback '%k' */
  59 typedef size_t (*ltt_serialize_cb)(struct ust_buffer *buf, size_t buf_offset,
  60                         struct ltt_serialize_closure *closure,
  61                         void *serialize_private, int *largest_align,
  62                         const char *fmt, va_list *args);
  63
  64 struct ltt_serialize_closure {
  65         ltt_serialize_cb *callbacks;
  66         long cb_args[LTT_NR_CALLBACKS];
  67         unsigned int cb_idx;
  68 };
  69
  70 extern size_t ltt_serialize_data(struct ust_buffer *buf, size_t buf_offset,
  71                         struct ltt_serialize_closure *closure,
  72                         void *serialize_private,
  73                         int *largest_align, const char *fmt, va_list *args);
  74
  75 struct ltt_available_probe {
  76         const char *name;               /* probe name */
  77         const char *format;
  78         marker_probe_func *probe_func;
  79         ltt_serialize_cb callbacks[LTT_NR_CALLBACKS];
  80         struct list_head node;          /* registered probes list */
  81 };
  82
  83 struct ltt_probe_private_data {
  84         struct ltt_trace_struct *trace; /*
  85                                          * Target trace, for metadata
  86                                          * or statedump.
  87                                          */
  88         ltt_serialize_cb serializer;    /*
  89                                          * Serialization function override.
  90                                          */
  91         void *serialize_private;        /*
  92                                          * Private data for serialization
  93                                          * functions.
  94                                          */
  95 };
  96
  97 enum ltt_channels {
  98         LTT_CHANNEL_METADATA,
  99         LTT_CHANNEL_UST,
 100 };
 101
 102 struct ltt_active_marker {
 103         struct list_head node;          /* active markers list */
 104         const char *channel;
 105         const char *name;
 106         const char *format;
 107         struct ltt_available_probe *probe;
 108 };
 109
 110 struct marker; //ust//
 111 extern void ltt_vtrace(const struct marker *mdata, void *probe_data,
 112         struct registers *regs, void *call_data, const char *fmt, va_list *args);
 113 extern void ltt_trace(const struct marker *mdata, void *probe_data,
 114         struct registers *regs, void *call_data, const char *fmt, ...);
 115
 116 /*
 117  * Unique ID assigned to each registered probe.
 118  */
 119 enum marker_id {
 120         MARKER_ID_SET_MARKER_ID = 0,    /* Static IDs available (range 0-7) */
 121         MARKER_ID_SET_MARKER_FORMAT,
 122         MARKER_ID_COMPACT,              /* Compact IDs (range: 8-127)       */
 123         MARKER_ID_DYNAMIC,              /* Dynamic IDs (range: 128-65535)   */
 124 };
 125
 126 /* static ids 0-1 reserved for internal use. */
 127 #define MARKER_CORE_IDS         2
 128 static inline enum marker_id marker_id_type(uint16_t id)
 129 {
 130         if (id < MARKER_CORE_IDS)
 131                 return (enum marker_id)id;
 132         else
 133                 return MARKER_ID_DYNAMIC;
 134 }
 135
 136 struct user_dbg_data {
 137         unsigned long avail_size;
 138         unsigned long write;
 139         unsigned long read;
 140 };
 141
 142 struct ltt_trace_ops {
 143         /* First 32 bytes cache-hot cacheline */
 144         int (*reserve_slot) (struct ltt_trace_struct *trace,
 145                                 struct ust_channel *channel,
 146                                 void **transport_data, size_t data_size,
 147                                 size_t *slot_size, long *buf_offset, u64 *tsc,
 148                                 unsigned int *rflags,
 149                                 int largest_align);
 150 //ust// void (*commit_slot) (struct ltt_channel_struct *channel,
 151 //ust//                         void **transport_data, long buf_offset,
 152 //ust//                         size_t slot_size);
 153         void (*wakeup_channel) (struct ust_channel *channel);
 154         int (*user_blocking) (struct ltt_trace_struct *trace,
 155                                 unsigned int index, size_t data_size,
 156                                 struct user_dbg_data *dbg);
 157         /* End of first 32 bytes cacheline */
 158         int (*create_dirs) (struct ltt_trace_struct *new_trace);
 159         void (*remove_dirs) (struct ltt_trace_struct *new_trace);
 160         int (*create_channel) (const char *trace_name,
 161                                 struct ltt_trace_struct *trace,
 162                                 const char *channel_name,
 163                                 struct ust_channel *channel,
 164                                 unsigned int subbuf_size,
 165                                 unsigned int n_subbufs, int overwrite);
 166         void (*finish_channel) (struct ust_channel *channel);
 167         void (*remove_channel) (struct ust_channel *channel);
 168         void (*user_errors) (struct ltt_trace_struct *trace,
 169                                 unsigned int index, size_t data_size,
 170                                 struct user_dbg_data *dbg);
 171 } ____cacheline_aligned;
 172
 173 struct ltt_transport {
 174         char *name;
 175         struct module *owner;
 176         struct list_head node;
 177         struct ltt_trace_ops ops;
 178 };
 179
 180 enum trace_mode { LTT_TRACE_NORMAL, LTT_TRACE_FLIGHT, LTT_TRACE_HYBRID };
 181
 182 #define CHANNEL_FLAG_ENABLE     (1U<<0)
 183 #define CHANNEL_FLAG_OVERWRITE  (1U<<1)
 184
 185 /* Per-trace information - each trace/flight recorder represented by one */
 186 struct ltt_trace_struct {
 187         /* First 32 bytes cache-hot cacheline */
 188         struct list_head list;
 189         struct ltt_trace_ops *ops;
 190         int active;
 191         /* Second 32 bytes cache-hot cacheline */
 192         struct ust_channel *channels;
 193         unsigned int nr_channels;
 194         u32 freq_scale;
 195         u64 start_freq;
 196         u64 start_tsc;
 197         unsigned long long start_monotonic;
 198         struct timeval          start_time;
 199         struct ltt_channel_setting *settings;
 200         struct {
 201                 struct dentry                   *trace_root;
 202         } dentry;
 203         struct kref kref; /* Each channel has a kref of the trace struct */
 204         struct ltt_transport *transport;
 205         struct kref ltt_transport_kref;
 206         char trace_name[NAME_MAX];
 207 } ____cacheline_aligned;
 208
 209 /* Hardcoded event headers
 210  *
 211  * event header for a trace with active heartbeat : 27 bits timestamps
 212  *
 213  * headers are 32-bits aligned. In order to insure such alignment, a dynamic per
 214  * trace alignment value must be done.
 215  *
 216  * Remember that the C compiler does align each member on the boundary
 217  * equivalent to their own size.
 218  *
 219  * As relay subbuffers are aligned on pages, we are sure that they are 4 and 8
 220  * bytes aligned, so the buffer header and trace header are aligned.
 221  *
 222  * Event headers are aligned depending on the trace alignment option.
 223  *
 224  * Note using C structure bitfields for cross-endianness and portability
 225  * concerns.
 226  */
 227
 228 #define LTT_RESERVED_EVENTS     3
 229 #define LTT_EVENT_BITS          5
 230 #define LTT_FREE_EVENTS         ((1 << LTT_EVENT_BITS) - LTT_RESERVED_EVENTS)
 231 #define LTT_TSC_BITS            27
 232 #define LTT_TSC_MASK            ((1 << LTT_TSC_BITS) - 1)
 233
 234 struct ltt_event_header {
 235         u32 id_time;            /* 5 bits event id (MSB); 27 bits time (LSB) */
 236 };
 237
 238 /* Reservation flags */
 239 #define LTT_RFLAG_ID                    (1 << 0)
 240 #define LTT_RFLAG_ID_SIZE               (1 << 1)
 241 #define LTT_RFLAG_ID_SIZE_TSC           (1 << 2)
 242
 243 /*
 244  * We use asm/timex.h : cpu_khz/HZ variable in here : we might have to deal
 245  * specifically with CPU frequency scaling someday, so using an interpolation
 246  * between the start and end of buffer values is not flexible enough. Using an
 247  * immediate frequency value permits to calculate directly the times for parts
 248  * of a buffer that would be before a frequency change.
 249  *
 250  * Keep the natural field alignment for _each field_ within this structure if
 251  * you ever add/remove a field from this header. Packed attribute is not used
 252  * because gcc generates poor code on at least powerpc and mips. Don't ever
 253  * let gcc add padding between the structure elements.
 254  */
 255 struct ltt_subbuffer_header {
 256         uint64_t cycle_count_begin;     /* Cycle count at subbuffer start */
 257         uint64_t cycle_count_end;       /* Cycle count at subbuffer end */
 258         uint32_t magic_number;          /*
 259                                          * Trace magic number.
 260                                          * contains endianness information.
 261                                          */
 262         uint8_t major_version;
 263         uint8_t minor_version;
 264         uint8_t arch_size;              /* Architecture pointer size */
 265         uint8_t alignment;              /* LTT data alignment */
 266         uint64_t start_time_sec;        /* NTP-corrected start time */
 267         uint64_t start_time_usec;
 268         uint64_t start_freq;            /*
 269                                          * Frequency at trace start,
 270                                          * used all along the trace.
 271                                          */
 272         uint32_t freq_scale;            /* Frequency scaling (divisor) */
 273         uint32_t lost_size;             /* Size unused at end of subbuffer */
 274         uint32_t buf_size;              /* Size of this subbuffer */
 275         uint32_t events_lost;           /*
 276                                          * Events lost in this subbuffer since
 277                                          * the beginning of the trace.
 278                                          * (may overflow)
 279                                          */
 280         uint32_t subbuf_corrupt;        /*
 281                                          * Corrupted (lost) subbuffers since
 282                                          * the begginig of the trace.
 283                                          * (may overflow)
 284                                          */
 285         uint8_t header_end[0];          /* End of header */
 286 };
 287
 288 /**
 289  * ltt_subbuffer_header_size - called on buffer-switch to a new sub-buffer
 290  *
 291  * Return header size without padding after the structure. Don't use packed
 292  * structure because gcc generates inefficient code on some architectures
 293  * (powerpc, mips..)
 294  */
 295 static inline size_t ltt_subbuffer_header_size(void)
 296 {
 297         return offsetof(struct ltt_subbuffer_header, header_end);
 298 }
 299
 300 /*
 301  * ust_get_header_size
 302  *
 303  * Calculate alignment offset to 32-bits. This is the alignment offset of the
 304  * event header.
 305  *
 306  * Important note :
 307  * The event header must be 32-bits. The total offset calculated here :
 308  *
 309  * Alignment of header struct on 32 bits (min arch size, header size)
 310  * + sizeof(header struct)  (32-bits)
 311  * + (opt) u16 (ext. event id)
 312  * + (opt) u16 (event_size) (if event_size == 0xFFFFUL, has ext. event size)
 313  * + (opt) u32 (ext. event size)
 314  * + (opt) u64 full TSC (aligned on min(64-bits, arch size))
 315  *
 316  * The payload must itself determine its own alignment from the biggest type it
 317  * contains.
 318  * */
 319 static inline unsigned char ust_get_header_size(
 320                 struct ust_channel *channel,
 321                 size_t offset,
 322                 size_t data_size,
 323                 size_t *before_hdr_pad,
 324                 unsigned int rflags)
 325 {
 326         size_t orig_offset = offset;
 327         size_t padding;
 328
 329         padding = ltt_align(offset, sizeof(struct ltt_event_header));
 330         offset += padding;
 331         offset += sizeof(struct ltt_event_header);
 332
 333         switch (rflags) {
 334         case LTT_RFLAG_ID_SIZE_TSC:
 335                 offset += sizeof(u16) + sizeof(u16);
 336                 if (data_size >= 0xFFFFU)
 337                         offset += sizeof(u32);
 338                 offset += ltt_align(offset, sizeof(u64));
 339                 offset += sizeof(u64);
 340                 break;
 341         case LTT_RFLAG_ID_SIZE:
 342                 offset += sizeof(u16) + sizeof(u16);
 343                 if (data_size >= 0xFFFFU)
 344                         offset += sizeof(u32);
 345                 break;
 346         case LTT_RFLAG_ID:
 347                 offset += sizeof(u16);
 348                 break;
 349         }
 350
 351         *before_hdr_pad = padding;
 352         return offset - orig_offset;
 353 }
 354
 355 /*
 356  * ltt_write_event_header
 357  *
 358  * Writes the event header to the offset (already aligned on 32-bits).
 359  *
 360  * @trace : trace to write to.
 361  * @channel : pointer to the channel structure..
 362  * @buf : buffer to write to.
 363  * @buf_offset : buffer offset to write to (aligned on 32 bits).
 364  * @eID : event ID
 365  * @event_size : size of the event, excluding the event header.
 366  * @tsc : time stamp counter.
 367  * @rflags : reservation flags.
 368  *
 369  * returns : offset where the event data must be written.
 370  */
 371 static inline size_t ltt_write_event_header(struct ltt_trace_struct *trace,
 372                 struct ust_buffer *buf, long buf_offset,
 373                 u16 eID, size_t event_size,
 374                 u64 tsc, unsigned int rflags)
 375 {
 376         struct ltt_event_header header;
 377         size_t small_size;
 378
 379         switch (rflags) {
 380         case LTT_RFLAG_ID_SIZE_TSC:
 381                 header.id_time = 29 << LTT_TSC_BITS;
 382                 break;
 383         case LTT_RFLAG_ID_SIZE:
 384                 header.id_time = 30 << LTT_TSC_BITS;
 385                 break;
 386         case LTT_RFLAG_ID:
 387                 header.id_time = 31 << LTT_TSC_BITS;
 388                 break;
 389         default:
 390                 header.id_time = eID << LTT_TSC_BITS;
 391                 break;
 392         }
 393         header.id_time |= (u32)tsc & LTT_TSC_MASK;
 394         ust_buffers_write(buf, buf_offset, &header, sizeof(header));
 395         buf_offset += sizeof(header);
 396
 397         switch (rflags) {
 398         case LTT_RFLAG_ID_SIZE_TSC:
 399                 small_size = min_t(size_t, event_size, 0xFFFFU);
 400                 ust_buffers_write(buf, buf_offset,
 401                         (u16[]){ (u16)eID }, sizeof(u16));
 402                 buf_offset += sizeof(u16);
 403                 ust_buffers_write(buf, buf_offset,
 404                         (u16[]){ (u16)small_size }, sizeof(u16));
 405                 buf_offset += sizeof(u16);
 406                 if (small_size == 0xFFFFU) {
 407                         ust_buffers_write(buf, buf_offset,
 408                                 (u32[]){ (u32)event_size }, sizeof(u32));
 409                         buf_offset += sizeof(u32);
 410                 }
 411                 buf_offset += ltt_align(buf_offset, sizeof(u64));
 412                 ust_buffers_write(buf, buf_offset,
 413                         (u64[]){ (u64)tsc }, sizeof(u64));
 414                 buf_offset += sizeof(u64);
 415                 break;
 416         case LTT_RFLAG_ID_SIZE:
 417                 small_size = min_t(size_t, event_size, 0xFFFFU);
 418                 ust_buffers_write(buf, buf_offset,
 419                         (u16[]){ (u16)eID }, sizeof(u16));
 420                 buf_offset += sizeof(u16);
 421                 ust_buffers_write(buf, buf_offset,
 422                         (u16[]){ (u16)small_size }, sizeof(u16));
 423                 buf_offset += sizeof(u16);
 424                 if (small_size == 0xFFFFU) {
 425                         ust_buffers_write(buf, buf_offset,
 426                                 (u32[]){ (u32)event_size }, sizeof(u32));
 427                         buf_offset += sizeof(u32);
 428                 }
 429                 break;
 430         case LTT_RFLAG_ID:
 431                 ust_buffers_write(buf, buf_offset,
 432                         (u16[]){ (u16)eID }, sizeof(u16));
 433                 buf_offset += sizeof(u16);
 434                 break;
 435         default:
 436                 break;
 437         }
 438
 439         return buf_offset;
 440 }
 441
 442 /* Lockless LTTng */
 443
 444 /*
 445  * ltt_reserve_slot
 446  *
 447  * Atomic slot reservation in a LTTng buffer. It will take care of
 448  * sub-buffer switching.
 449  *
 450  * Parameters:
 451  *
 452  * @trace : the trace structure to log to.
 453  * @channel : the chanel to reserve space into.
 454  * @transport_data : specific transport data.
 455  * @data_size : size of the variable length data to log.
 456  * @slot_size : pointer to total size of the slot (out)
 457  * @buf_offset : pointer to reserve offset (out)
 458  * @tsc : pointer to the tsc at the slot reservation (out)
 459  * @rflags : reservation flags (header specificity)
 460  * @cpu : cpu id
 461  *
 462  * Return : -ENOSPC if not enough space, else 0.
 463  */
 464 static inline int ltt_reserve_slot(
 465                 struct ltt_trace_struct *trace,
 466                 struct ust_channel *channel,
 467                 void **transport_data,
 468                 size_t data_size,
 469                 size_t *slot_size,
 470                 long *buf_offset,
 471                 u64 *tsc,
 472                 unsigned int *rflags,
 473                 int largest_align)
 474 {
 475         return trace->ops->reserve_slot(trace, channel, transport_data,
 476                         data_size, slot_size, buf_offset, tsc, rflags,
 477                         largest_align);
 478 }
 479
 480
 481 ///*
 482 // * ltt_commit_slot
 483 // *
 484 // * Atomic unordered slot commit. Increments the commit count in the
 485 // * specified sub-buffer, and delivers it if necessary.
 486 // *
 487 // * Parameters:
 488 // *
 489 // * @channel : the chanel to reserve space into.
 490 // * @transport_data : specific transport data.
 491 // * @buf_offset : offset of beginning of reserved slot
 492 // * @slot_size : size of the reserved slot.
 493 // */
 494 //static inline void ltt_commit_slot(
 495 //              struct ltt_channel_struct *channel,
 496 //              void **transport_data,
 497 //              long buf_offset,
 498 //              size_t slot_size)
 499 //{
 500 //      struct ltt_trace_struct *trace = channel->trace;
 501 //
 502 //      trace->ops->commit_slot(channel, transport_data, buf_offset, slot_size);
 503 //}
 504
 505 /*
 506  * Control channels :
 507  * control/metadata
 508  * control/interrupts
 509  * control/...
 510  *
 511  * cpu channel :
 512  * cpu
 513  */
 514
 515 #define LTT_METADATA_CHANNEL            "metadata_state"
 516 #define LTT_UST_CHANNEL                 "ust"
 517
 518 #define LTT_FLIGHT_PREFIX       "flight-"
 519
 520 /* Tracer properties */
 521 //#define LTT_DEFAULT_SUBBUF_SIZE_LOW   134217728
 522 #define LTT_DEFAULT_SUBBUF_SIZE_LOW     65536
 523 //#define LTT_DEFAULT_SUBBUF_SIZE_LOW   4096
 524 #define LTT_DEFAULT_N_SUBBUFS_LOW       2
 525 //#define LTT_DEFAULT_SUBBUF_SIZE_MED   134217728
 526 #define LTT_DEFAULT_SUBBUF_SIZE_MED     262144
 527 //#define LTT_DEFAULT_SUBBUF_SIZE_MED   4096
 528 #define LTT_DEFAULT_N_SUBBUFS_MED       2
 529 //#define LTT_DEFAULT_SUBBUF_SIZE_HIGH  134217728
 530 #define LTT_DEFAULT_SUBBUF_SIZE_HIGH    1048576
 531 //#define LTT_DEFAULT_SUBBUF_SIZE_HIGH  4096
 532 #define LTT_DEFAULT_N_SUBBUFS_HIGH      2
 533 #define LTT_TRACER_MAGIC_NUMBER         0x00D6B7ED
 534 #define LTT_TRACER_VERSION_MAJOR        2
 535 #define LTT_TRACER_VERSION_MINOR        3
 536
 537 /*
 538  * Size reserved for high priority events (interrupts, NMI, BH) at the end of a
 539  * nearly full buffer. User space won't use this last amount of space when in
 540  * blocking mode. This space also includes the event header that would be
 541  * written by this user space event.
 542  */
 543 #define LTT_RESERVE_CRITICAL            4096
 544
 545 /* Register and unregister function pointers */
 546
 547 enum ltt_module_function {
 548         LTT_FUNCTION_RUN_FILTER,
 549         LTT_FUNCTION_FILTER_CONTROL,
 550         LTT_FUNCTION_STATEDUMP
 551 };
 552
 553 extern void ltt_transport_register(struct ltt_transport *transport);
 554 extern void ltt_transport_unregister(struct ltt_transport *transport);
 555
 556 /* Exported control function */
 557
 558 union ltt_control_args {
 559         struct {
 560                 enum trace_mode mode;
 561                 unsigned int subbuf_size_low;
 562                 unsigned int n_subbufs_low;
 563                 unsigned int subbuf_size_med;
 564                 unsigned int n_subbufs_med;
 565                 unsigned int subbuf_size_high;
 566                 unsigned int n_subbufs_high;
 567         } new_trace;
 568 };
 569
 570 extern int _ltt_trace_setup(const char *trace_name);
 571 extern int ltt_trace_setup(const char *trace_name);
 572 extern struct ltt_trace_struct *_ltt_trace_find_setup(const char *trace_name);
 573 extern int ltt_trace_set_type(const char *trace_name, const char *trace_type);
 574 extern int ltt_trace_set_channel_subbufsize(const char *trace_name,
 575                 const char *channel_name, unsigned int size);
 576 extern int ltt_trace_set_channel_subbufcount(const char *trace_name,
 577                 const char *channel_name, unsigned int cnt);
 578 extern int ltt_trace_set_channel_enable(const char *trace_name,
 579                 const char *channel_name, unsigned int enable);
 580 extern int ltt_trace_set_channel_overwrite(const char *trace_name,
 581                 const char *channel_name, unsigned int overwrite);
 582 extern int ltt_trace_alloc(const char *trace_name);
 583 extern int ltt_trace_destroy(const char *trace_name);
 584 extern int ltt_trace_start(const char *trace_name);
 585 extern int ltt_trace_stop(const char *trace_name);
 586
 587 enum ltt_filter_control_msg {
 588         LTT_FILTER_DEFAULT_ACCEPT,
 589         LTT_FILTER_DEFAULT_REJECT
 590 };
 591
 592 extern int ltt_filter_control(enum ltt_filter_control_msg msg,
 593                 const char *trace_name);
 594
 595 extern struct dentry *get_filter_root(void);
 596
 597 extern void ltt_write_trace_header(struct ltt_trace_struct *trace,
 598                 struct ltt_subbuffer_header *header);
 599 extern void ltt_buffer_destroy(struct ust_channel *ltt_chan);
 600
 601 extern void ltt_core_register(int (*function)(u8, void *));
 602
 603 extern void ltt_core_unregister(void);
 604
 605 extern void ltt_release_trace(struct kref *kref);
 606 extern void ltt_release_transport(struct kref *kref);
 607
 608 extern int ltt_probe_register(struct ltt_available_probe *pdata);
 609 extern int ltt_probe_unregister(struct ltt_available_probe *pdata);
 610 extern int ltt_marker_connect(const char *channel, const char *mname,
 611                 const char *pname);
 612 extern int ltt_marker_disconnect(const char *channel, const char *mname,
 613                 const char *pname);
 614 extern void ltt_dump_marker_state(struct ltt_trace_struct *trace);
 615
 616 extern void ltt_lock_traces(void);
 617 extern void ltt_unlock_traces(void);
 618
 619 extern struct ltt_trace_struct *_ltt_trace_find(const char *trace_name);
 620
 621 #endif /* _LTT_TRACER_H */