include/lttng/tracepoint.h

   1 #ifndef _LTTNG_TRACEPOINT_H
   2 #define _LTTNG_TRACEPOINT_H
   3
   4 /*
   5  * Copyright (c) 2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   6  *
   7  * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
   8  * OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
   9  *
  10  * Permission is hereby granted to use or copy this program
  11  * for any purpose,  provided the above notices are retained on all copies.
  12  * Permission to modify the code and to distribute modified code is granted,
  13  * provided the above notices are retained, and a notice that the code was
  14  * modified is included with the above copyright notice.
  15  */
  16
  17 #include <lttng/tracepoint-types.h>
  18 #include <lttng/tracepoint-rcu.h>
  19 #include <urcu/compiler.h>
  20 #include <dlfcn.h>      /* for dlopen */
  21 #include <string.h>     /* for memset */
  22 #include <assert.h>
  23
  24 #ifdef __cplusplus
  25 extern "C" {
  26 #endif
  27
  28 #define tracepoint(provider, name, ...)                                     \
  29         do {                                                                \
  30                 if (caa_unlikely(__tracepoint_##provider##___##name.state)) \
  31                         __tracepoint_cb_##provider##___##name(__VA_ARGS__); \
  32         } while (0)
  33
  34 #define TP_ARGS(...)       __VA_ARGS__
  35
  36 /*
  37  * TP_ARGS takes tuples of type, argument separated by a comma.
  38  * It can take up to 10 tuples (which means that less than 10 tuples is
  39  * fine too).
  40  * Each tuple is also separated by a comma.
  41  */
  42 #define __TP_COMBINE_TOKENS(_tokena, _tokenb)                           \
  43                 _tokena##_tokenb
  44 #define _TP_COMBINE_TOKENS(_tokena, _tokenb)                            \
  45                 __TP_COMBINE_TOKENS(_tokena, _tokenb)
  46 #define __TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc)                 \
  47                 _tokena##_tokenb##_tokenc
  48 #define _TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc)                  \
  49                 __TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc)
  50 #define __TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend)        \
  51                 _tokena##_tokenb##_tokenc##_tokend
  52 #define _TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend)         \
  53                 __TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend)
  54
  55 /* _TP_EXVAR* extract the var names. */
  56 #define _TP_EXVAR0()
  57 #define _TP_EXVAR2(a,b)                                         b
  58 #define _TP_EXVAR4(a,b,c,d)                                     b,d
  59 #define _TP_EXVAR6(a,b,c,d,e,f)                                 b,d,f
  60 #define _TP_EXVAR8(a,b,c,d,e,f,g,h)                             b,d,f,h
  61 #define _TP_EXVAR10(a,b,c,d,e,f,g,h,i,j)                        b,d,f,h,j
  62 #define _TP_EXVAR12(a,b,c,d,e,f,g,h,i,j,k,l)                    b,d,f,h,j,l
  63 #define _TP_EXVAR14(a,b,c,d,e,f,g,h,i,j,k,l,m,n)                b,d,f,h,j,l,n
  64 #define _TP_EXVAR16(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p)            b,d,f,h,j,l,n,p
  65 #define _TP_EXVAR18(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r)        b,d,f,h,j,l,n,p,r
  66 #define _TP_EXVAR20(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t)    b,d,f,h,j,l,n,p,r,t
  67
  68 #define _TP_EXDATA_VAR0()                                               __tp_data
  69 #define _TP_EXDATA_VAR2(a,b)                                            __tp_data,b
  70 #define _TP_EXDATA_VAR4(a,b,c,d)                                        __tp_data,b,d
  71 #define _TP_EXDATA_VAR6(a,b,c,d,e,f)                                    __tp_data,b,d,f
  72 #define _TP_EXDATA_VAR8(a,b,c,d,e,f,g,h)                                __tp_data,b,d,f,h
  73 #define _TP_EXDATA_VAR10(a,b,c,d,e,f,g,h,i,j)                           __tp_data,b,d,f,h,j
  74 #define _TP_EXDATA_VAR12(a,b,c,d,e,f,g,h,i,j,k,l)                       __tp_data,b,d,f,h,j,l
  75 #define _TP_EXDATA_VAR14(a,b,c,d,e,f,g,h,i,j,k,l,m,n)                   __tp_data,b,d,f,h,j,l,n
  76 #define _TP_EXDATA_VAR16(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p)               __tp_data,b,d,f,h,j,l,n,p
  77 #define _TP_EXDATA_VAR18(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r)           __tp_data,b,d,f,h,j,l,n,p,r
  78 #define _TP_EXDATA_VAR20(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t)       __tp_data,b,d,f,h,j,l,n,p,r,t
  79
  80 /* _TP_EXPROTO* extract tuples of type, var */
  81 #define _TP_EXPROTO0()
  82 #define _TP_EXPROTO2(a,b)                                       a b
  83 #define _TP_EXPROTO4(a,b,c,d)                                   a b,c d
  84 #define _TP_EXPROTO6(a,b,c,d,e,f)                               a b,c d,e f
  85 #define _TP_EXPROTO8(a,b,c,d,e,f,g,h)                           a b,c d,e f,g h
  86 #define _TP_EXPROTO10(a,b,c,d,e,f,g,h,i,j)                      a b,c d,e f,g h,i j
  87 #define _TP_EXPROTO12(a,b,c,d,e,f,g,h,i,j,k,l)                  a b,c d,e f,g h,i j,k l
  88 #define _TP_EXPROTO14(a,b,c,d,e,f,g,h,i,j,k,l,m,n)              a b,c d,e f,g h,i j,k l,m n
  89 #define _TP_EXPROTO16(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p)          a b,c d,e f,g h,i j,k l,m n,o p
  90 #define _TP_EXPROTO18(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r)      a b,c d,e f,g h,i j,k l,m n,o p,q r
  91 #define _TP_EXPROTO20(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t)  a b,c d,e f,g h,i j,k l,m n,o p,q r,s t
  92
  93 #define _TP_EXDATA_PROTO0()                                             void *__tp_data
  94 #define _TP_EXDATA_PROTO2(a,b)                                          void *__tp_data,a b
  95 #define _TP_EXDATA_PROTO4(a,b,c,d)                                      void *__tp_data,a b,c d
  96 #define _TP_EXDATA_PROTO6(a,b,c,d,e,f)                                  void *__tp_data,a b,c d,e f
  97 #define _TP_EXDATA_PROTO8(a,b,c,d,e,f,g,h)                              void *__tp_data,a b,c d,e f,g h
  98 #define _TP_EXDATA_PROTO10(a,b,c,d,e,f,g,h,i,j)                         void *__tp_data,a b,c d,e f,g h,i j
  99 #define _TP_EXDATA_PROTO12(a,b,c,d,e,f,g,h,i,j,k,l)                     void *__tp_data,a b,c d,e f,g h,i j,k l
 100 #define _TP_EXDATA_PROTO14(a,b,c,d,e,f,g,h,i,j,k,l,m,n)                 void *__tp_data,a b,c d,e f,g h,i j,k l,m n
 101 #define _TP_EXDATA_PROTO16(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p)             void *__tp_data,a b,c d,e f,g h,i j,k l,m n,o p
 102 #define _TP_EXDATA_PROTO18(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r)         void *__tp_data,a b,c d,e f,g h,i j,k l,m n,o p,q r
 103 #define _TP_EXDATA_PROTO20(a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t)     void *__tp_data,a b,c d,e f,g h,i j,k l,m n,o p,q r,s t
 104
 105 /* Preprocessor trick to count arguments. Inspired from sdt.h. */
 106 #define _TP_NARGS(...)                  __TP_NARGS(__VA_ARGS__, 20,19,18,17,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,1,0)
 107 #define __TP_NARGS(_0,_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,_11,_12,_13,_14,_15,_16,_17,_18,_19,_20, N, ...)   N
 108 #define _TP_PROTO_N(N, ...)             _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXPROTO, N)(__VA_ARGS__))
 109 #define _TP_VAR_N(N, ...)               _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXVAR, N)(__VA_ARGS__))
 110 #define _TP_DATA_PROTO_N(N, ...)        _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXDATA_PROTO, N)(__VA_ARGS__))
 111 #define _TP_DATA_VAR_N(N, ...)          _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXDATA_VAR, N)(__VA_ARGS__))
 112 #define _TP_ARGS_PROTO(...)             _TP_PROTO_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
 113 #define _TP_ARGS_VAR(...)               _TP_VAR_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
 114 #define _TP_ARGS_DATA_PROTO(...)        _TP_DATA_PROTO_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
 115 #define _TP_ARGS_DATA_VAR(...)          _TP_DATA_VAR_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
 116 #define _TP_PARAMS(...)                 __VA_ARGS__
 117
 118 #define _DECLARE_TRACEPOINT(_provider, _name, ...)                                      \
 119 extern struct tracepoint __tracepoint_##_provider##___##_name;                          \
 120 static inline void __tracepoint_cb_##_provider##___##_name(_TP_ARGS_PROTO(__VA_ARGS__)) \
 121 {                                                                                       \
 122         struct tracepoint_probe *__tp_probe;                                            \
 123                                                                                         \
 124         if (!TP_RCU_LINK_TEST())                                                        \
 125                 return;                                                                 \
 126         tp_rcu_read_lock_bp();                                                          \
 127         __tp_probe = tp_rcu_dereference_bp(__tracepoint_##_provider##___##_name.probes); \
 128         if (caa_unlikely(!__tp_probe))                                                  \
 129                 goto end;                                                               \
 130         do {                                                                            \
 131                 void *__tp_cb = __tp_probe->func;                                       \
 132                 void *__tp_data = __tp_probe->data;                                     \
 133                                                                                         \
 134                 URCU_FORCE_CAST(void (*)(_TP_ARGS_DATA_PROTO(__VA_ARGS__)), __tp_cb)    \
 135                                 (_TP_ARGS_DATA_VAR(__VA_ARGS__));                       \
 136         } while ((++__tp_probe)->func);                                                 \
 137 end:                                                                                    \
 138         tp_rcu_read_unlock_bp();                                                        \
 139 }                                                                                       \
 140 static inline void __tracepoint_register_##_provider##___##_name(char *name,            \
 141                 void *func, void *data)                                                 \
 142 {                                                                                       \
 143         __tracepoint_probe_register(name, func, data);                                  \
 144 }                                                                                       \
 145 static inline void __tracepoint_unregister_##_provider##___##_name(char *name,          \
 146                 void *func, void *data)                                                 \
 147 {                                                                                       \
 148         __tracepoint_probe_unregister(name, func, data);                                \
 149 }
 150
 151 extern int __tracepoint_probe_register(const char *name, void *func, void *data);
 152 extern int __tracepoint_probe_unregister(const char *name, void *func, void *data);
 153
 154 /*
 155  * tracepoint dynamic linkage handling (callbacks). Hidden visibility:
 156  * shared across objects in a module/main executable.
 157  */
 158 struct tracepoint_dlopen {
 159         void *liblttngust_handle;
 160
 161         int (*tracepoint_register_lib)(struct tracepoint * const *tracepoints_start,
 162                 int tracepoints_count);
 163         int (*tracepoint_unregister_lib)(struct tracepoint * const *tracepoints_start);
 164 #ifndef _LGPL_SOURCE
 165         void (*rcu_read_lock_sym_bp)(void);
 166         void (*rcu_read_unlock_sym_bp)(void);
 167         void *(*rcu_dereference_sym_bp)(void *p);
 168 #endif
 169 };
 170
 171 extern struct tracepoint_dlopen tracepoint_dlopen;
 172
 173 #ifdef TRACEPOINT_DEFINE
 174
 175 /*
 176  * When TRACEPOINT_PROBE_DYNAMIC_LINKAGE is defined, we do not emit a
 177  * unresolved symbol that requires the provider to be linked in. When
 178  * TRACEPOINT_PROBE_DYNAMIC_LINKAGE is not defined, we emit an
 179  * unresolved symbol that depends on having the provider linked in,
 180  * otherwise the linker complains. This deals with use of static
 181  * libraries, ensuring that the linker does not remove the provider
 182  * object from the executable.
 183  */
 184 #ifdef TRACEPOINT_PROBE_DYNAMIC_LINKAGE
 185 #define _TRACEPOINT_UNDEFINED_REF(provider)
 186 #else   /* TRACEPOINT_PROBE_DYNAMIC_LINKAGE */
 187 #define _TRACEPOINT_UNDEFINED_REF(provider)     \
 188         &__tracepoint_provider_##provider,
 189 #endif /* TRACEPOINT_PROBE_DYNAMIC_LINKAGE */
 190
 191 /*
 192  * Note: to allow PIC code, we need to allow the linker to update the pointers
 193  * in the __tracepoints_ptrs section.
 194  * Therefore, this section is _not_ const (read-only).
 195  */
 196 #define _DEFINE_TRACEPOINT(provider, name)                                      \
 197         extern int __tracepoint_provider_##provider;                            \
 198         static const char __tp_strtab_##provider##___##name[]                   \
 199                 __attribute__((section("__tracepoints_strings"))) =             \
 200                         #provider ":" #name;                                    \
 201         struct tracepoint __tracepoint_##provider##___##name                    \
 202                 __attribute__((section("__tracepoints"))) =                     \
 203                         { __tp_strtab_##provider##___##name, 0, NULL, _TRACEPOINT_UNDEFINED_REF(provider) };            \
 204         static struct tracepoint * __tracepoint_ptr_##provider##___##name       \
 205                 __attribute__((used, section("__tracepoints_ptrs"))) =          \
 206                         &__tracepoint_##provider##___##name;
 207
 208 /*
 209  * These weak symbols, the constructor, and destructor take care of
 210  * registering only _one_ instance of the tracepoints per shared-ojbect
 211  * (or for the whole main program).
 212  */
 213 extern struct tracepoint * const __start___tracepoints_ptrs[]
 214         __attribute__((weak, visibility("hidden")));
 215 extern struct tracepoint * const __stop___tracepoints_ptrs[]
 216         __attribute__((weak, visibility("hidden")));
 217 int __tracepoint_registered
 218         __attribute__((weak, visibility("hidden")));
 219 struct tracepoint_dlopen tracepoint_dlopen
 220         __attribute__((weak, visibility("hidden")));
 221
 222 static void __attribute__((constructor)) __tracepoints__init(void)
 223 {
 224         if (__tracepoint_registered++)
 225                 return;
 226
 227         tracepoint_dlopen.liblttngust_handle =
 228                 dlopen("liblttng-ust-tracepoint.so.0", RTLD_NOW | RTLD_GLOBAL);
 229         if (!tracepoint_dlopen.liblttngust_handle)
 230                 return;
 231         tracepoint_dlopen.tracepoint_register_lib =
 232                 URCU_FORCE_CAST(int (*)(struct tracepoint * const *, int),
 233                                 dlsym(tracepoint_dlopen.liblttngust_handle,
 234                                         "tracepoint_register_lib"));
 235         tracepoint_dlopen.tracepoint_unregister_lib =
 236                 URCU_FORCE_CAST(int (*)(struct tracepoint * const *),
 237                                 dlsym(tracepoint_dlopen.liblttngust_handle,
 238                                         "tracepoint_unregister_lib"));
 239 #ifndef _LGPL_SOURCE
 240         tracepoint_dlopen.rcu_read_lock_sym_bp =
 241                 URCU_FORCE_CAST(void (*)(void),
 242                                 dlsym(tracepoint_dlopen.liblttngust_handle,
 243                                         "tp_rcu_read_lock_bp"));
 244         tracepoint_dlopen.rcu_read_unlock_sym_bp =
 245                 URCU_FORCE_CAST(void (*)(void),
 246                                 dlsym(tracepoint_dlopen.liblttngust_handle,
 247                                         "tp_rcu_read_unlock_bp"));
 248         tracepoint_dlopen.rcu_dereference_sym_bp =
 249                 URCU_FORCE_CAST(void *(*)(void *p),
 250                                 dlsym(tracepoint_dlopen.liblttngust_handle,
 251                                         "tp_rcu_dereference_sym_bp"));
 252 #endif
 253         tracepoint_dlopen.tracepoint_register_lib(__start___tracepoints_ptrs,
 254                                 __stop___tracepoints_ptrs -
 255                                 __start___tracepoints_ptrs);
 256 }
 257
 258 static void __attribute__((destructor)) __tracepoints__destroy(void)
 259 {
 260         int ret;
 261
 262         if (--__tracepoint_registered)
 263                 return;
 264         if (tracepoint_dlopen.tracepoint_unregister_lib)
 265                 tracepoint_dlopen.tracepoint_unregister_lib(__start___tracepoints_ptrs);
 266         if (tracepoint_dlopen.liblttngust_handle) {
 267                 ret = dlclose(tracepoint_dlopen.liblttngust_handle);
 268                 assert(!ret);
 269                 memset(&tracepoint_dlopen, 0, sizeof(tracepoint_dlopen));
 270         }
 271 }
 272
 273 #else /* TRACEPOINT_DEFINE */
 274
 275 #define _DEFINE_TRACEPOINT(provider, name)
 276
 277 #endif /* #else TRACEPOINT_DEFINE */
 278
 279 #ifdef __cplusplus
 280 }
 281 #endif
 282
 283 #endif /* _LTTNG_TRACEPOINT_H */
 284
 285 /* The following declarations must be outside re-inclusion protection. */
 286
 287 #ifndef TRACEPOINT_EVENT
 288
 289 /*
 290  * How to use the TRACEPOINT_EVENT macro:
 291  *
 292  * An example:
 293  *
 294  * TRACEPOINT_EVENT(someproject_component, event_name,
 295  *
 296  *     * TP_ARGS takes from 0 to 10 "type, field_name" pairs *
 297  *
 298  *     TP_ARGS(int, arg0, void *, arg1, char *, string, size_t, strlen,
 299  *             long *, arg4, size_t, arg4_len),
 300  *
 301  *      * TP_FIELDS describes the event payload layout in the trace *
 302  *
 303  *     TP_FIELDS(
 304  *         * Integer, printed in base 10 *
 305  *         ctf_integer(int, field_a, arg0)
 306  *
 307  *         * Integer, printed with 0x base 16 *
 308  *         ctf_integer_hex(unsigned long, field_d, arg1)
 309  *
 310  *         * Array Sequence, printed as UTF8-encoded array of bytes *
 311  *         ctf_array_text(char, field_b, string, FIXED_LEN)
 312  *         ctf_sequence_text(char, field_c, string, size_t, strlen)
 313  *
 314  *         * String, printed as UTF8-encoded string *
 315  *         ctf_string(field_e, string)
 316  *
 317  *         * Array sequence of signed integer values *
 318  *         ctf_array(long, field_f, arg4, FIXED_LEN4)
 319  *         ctf_sequence(long, field_g, arg4, size_t, arg4_len)
 320  *     )
 321  * )
 322  *
 323  * More detailed explanation:
 324  *
 325  * The name of the tracepoint is expressed as a tuple with the provider
 326  * and name arguments.
 327  *
 328  * The provider and name should be a proper C99 identifier.
 329  * The "provider" and "name" MUST follow these rules to ensure no
 330  * namespace clash occurs:
 331  *
 332  * For projects (applications and libraries) for which an entity
 333  * specific to the project controls the source code and thus its
 334  * tracepoints (typically with a scope larger than a single company):
 335  *
 336  * either:
 337  *   project_component, event
 338  * or:
 339  *   project, event
 340  *
 341  * Where "project" is the name of the project,
 342  *       "component" is the name of the project component (which may
 343  *       include several levels of sub-components, e.g.
 344  *       ...component_subcomponent_...) where the tracepoint is located
 345  *       (optional),
 346  *       "event" is the name of the tracepoint event.
 347  *
 348  * For projects issued from a single company wishing to advertise that
 349  * the company controls the source code and thus the tracepoints, the
 350  * "com_" prefix should be used:
 351  *
 352  * either:
 353  *   com_company_project_component, event
 354  * or:
 355  *   com_company_project, event
 356  *
 357  * Where "company" is the name of the company,
 358  *       "project" is the name of the project,
 359  *       "component" is the name of the project component (which may
 360  *       include several levels of sub-components, e.g.
 361  *       ...component_subcomponent_...) where the tracepoint is located
 362  *       (optional),
 363  *       "event" is the name of the tracepoint event.
 364  *
 365  * the provider:event identifier is limited to 127 characters.
 366  */
 367
 368 #define TRACEPOINT_EVENT(provider, name, args, fields)                  \
 369         _DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args))           \
 370         _DEFINE_TRACEPOINT(provider, name)
 371
 372 #define TRACEPOINT_EVENT_CLASS(provider, name, args, fields)
 373
 374 #define TRACEPOINT_EVENT_INSTANCE(provider, _template, name, args)      \
 375         _DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args))           \
 376         _DEFINE_TRACEPOINT(provider, name)
 377
 378 #endif /* #ifndef TRACEPOINT_EVENT */
 379
 380 #ifndef TRACEPOINT_LOGLEVEL
 381
 382 /*
 383  * Tracepoint Loglevels
 384  *
 385  * Typical use of these loglevels:
 386  *
 387  * The loglevels go from 0 to 14. Higher numbers imply the most
 388  * verbosity (higher event throughput expected.
 389  *
 390  * Loglevels 0 through 6, and loglevel 14, match syslog(3) loglevels
 391  * semantic. Loglevels 7 through 13 offer more fine-grained selection of
 392  * debug information.
 393  *
 394  * TRACE_EMERG           0
 395  * system is unusable
 396  *
 397  * TRACE_ALERT           1
 398  * action must be taken immediately
 399  *
 400  * TRACE_CRIT            2
 401  * critical conditions
 402  *
 403  * TRACE_ERR             3
 404  * error conditions
 405  *
 406  * TRACE_WARNING         4
 407  * warning conditions
 408  *
 409  * TRACE_NOTICE          5
 410  * normal, but significant, condition
 411  *
 412  * TRACE_INFO            6
 413  * informational message
 414  *
 415  * TRACE_DEBUG_SYSTEM    7
 416  * debug information with system-level scope (set of programs)
 417  *
 418  * TRACE_DEBUG_PROGRAM   8
 419  * debug information with program-level scope (set of processes)
 420  *
 421  * TRACE_DEBUG_PROCESS   9
 422  * debug information with process-level scope (set of modules)
 423  *
 424  * TRACE_DEBUG_MODULE    10
 425  * debug information with module (executable/library) scope (set of units)
 426  *
 427  * TRACE_DEBUG_UNIT      11
 428  * debug information with compilation unit scope (set of functions)
 429  *
 430  * TRACE_DEBUG_FUNCTION  12
 431  * debug information with function-level scope
 432  *
 433  * TRACE_DEBUG_LINE      13
 434  * debug information with line-level scope (TRACEPOINT_EVENT default)
 435  *
 436  * TRACE_DEBUG           14
 437  * debug-level message (trace_printf default)
 438  *
 439  * Declare tracepoint loglevels for tracepoints. A TRACEPOINT_EVENT
 440  * should be declared prior to the the TRACEPOINT_LOGLEVEL for a given
 441  * tracepoint name. The first field is the name of the tracepoint, the
 442  * second field is the loglevel name.
 443  *
 444  *      TRACEPOINT_LOGLEVEL(< [com_company_]project[_component] >, < event >,
 445  *              < loglevel_name >)
 446  *
 447  * The TRACEPOINT_PROVIDER must be already declared before declaring a
 448  * TRACEPOINT_LOGLEVEL.
 449  */
 450
 451 enum {
 452         TRACE_EMERG             = 0,
 453         TRACE_ALERT             = 1,
 454         TRACE_CRIT              = 2,
 455         TRACE_ERR               = 3,
 456         TRACE_WARNING           = 4,
 457         TRACE_NOTICE            = 5,
 458         TRACE_INFO              = 6,
 459         TRACE_DEBUG_SYSTEM      = 7,
 460         TRACE_DEBUG_PROGRAM     = 8,
 461         TRACE_DEBUG_PROCESS     = 9,
 462         TRACE_DEBUG_MODULE      = 10,
 463         TRACE_DEBUG_UNIT        = 11,
 464         TRACE_DEBUG_FUNCTION    = 12,
 465         TRACE_DEBUG_LINE        = 13,
 466         TRACE_DEBUG             = 14,
 467 };
 468
 469 #define TRACEPOINT_LOGLEVEL(provider, name, loglevel)
 470
 471 #endif /* #ifndef TRACEPOINT_LOGLEVEL */