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 #include <lttng/ust-config.h>   /* for sdt */
  24
  25 #ifdef LTTNG_UST_HAVE_SDT_INTEGRATION
  26 #define SDT_USE_VARIADIC
  27 #include <sys/sdt.h>
  28 #else
  29 #define STAP_PROBEV(...)
  30 #endif
  31
  32 #ifdef __cplusplus
  33 extern "C" {
  34 #endif
  35
  36 #define tracepoint(provider, name, ...)                                     \
  37         do {                                                                \
  38                 STAP_PROBEV(provider, name, ## __VA_ARGS__);                \
  39                 if (caa_unlikely(__tracepoint_##provider##___##name.state)) \
  40                         __tracepoint_cb_##provider##___##name(__VA_ARGS__); \
  41         } while (0)
  42
  43 #define TP_ARGS(...)       __VA_ARGS__
  44
  45 /*
  46  * TP_ARGS takes tuples of type, argument separated by a comma.
  47  * It can take up to 10 tuples (which means that less than 10 tuples is
  48  * fine too).
  49  * Each tuple is also separated by a comma.
  50  */
  51 #define __TP_COMBINE_TOKENS(_tokena, _tokenb)                           \
  52                 _tokena##_tokenb
  53 #define _TP_COMBINE_TOKENS(_tokena, _tokenb)                            \
  54                 __TP_COMBINE_TOKENS(_tokena, _tokenb)
  55 #define __TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc)                 \
  56                 _tokena##_tokenb##_tokenc
  57 #define _TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc)                  \
  58                 __TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc)
  59 #define __TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend)        \
  60                 _tokena##_tokenb##_tokenc##_tokend
  61 #define _TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend)         \
  62                 __TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend)
  63
  64 /* _TP_EXVAR* extract the var names. */
  65 #define _TP_EXVAR0()
  66 #define _TP_EXVAR2(a,b)                                         b
  67 #define _TP_EXVAR4(a,b,c,d)                                     b,d
  68 #define _TP_EXVAR6(a,b,c,d,e,f)                                 b,d,f
  69 #define _TP_EXVAR8(a,b,c,d,e,f,g,h)                             b,d,f,h
  70 #define _TP_EXVAR10(a,b,c,d,e,f,g,h,i,j)                        b,d,f,h,j
  71 #define _TP_EXVAR12(a,b,c,d,e,f,g,h,i,j,k,l)                    b,d,f,h,j,l
  72 #define _TP_EXVAR14(a,b,c,d,e,f,g,h,i,j,k,l,m,n)                b,d,f,h,j,l,n
  73 #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
  74 #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
  75 #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
  76
  77 #define _TP_EXDATA_VAR0()                                               __tp_data
  78 #define _TP_EXDATA_VAR2(a,b)                                            __tp_data,b
  79 #define _TP_EXDATA_VAR4(a,b,c,d)                                        __tp_data,b,d
  80 #define _TP_EXDATA_VAR6(a,b,c,d,e,f)                                    __tp_data,b,d,f
  81 #define _TP_EXDATA_VAR8(a,b,c,d,e,f,g,h)                                __tp_data,b,d,f,h
  82 #define _TP_EXDATA_VAR10(a,b,c,d,e,f,g,h,i,j)                           __tp_data,b,d,f,h,j
  83 #define _TP_EXDATA_VAR12(a,b,c,d,e,f,g,h,i,j,k,l)                       __tp_data,b,d,f,h,j,l
  84 #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
  85 #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
  86 #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
  87 #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
  88
  89 /* _TP_EXPROTO* extract tuples of type, var */
  90 #define _TP_EXPROTO0()
  91 #define _TP_EXPROTO2(a,b)                                       a b
  92 #define _TP_EXPROTO4(a,b,c,d)                                   a b,c d
  93 #define _TP_EXPROTO6(a,b,c,d,e,f)                               a b,c d,e f
  94 #define _TP_EXPROTO8(a,b,c,d,e,f,g,h)                           a b,c d,e f,g h
  95 #define _TP_EXPROTO10(a,b,c,d,e,f,g,h,i,j)                      a b,c d,e f,g h,i j
  96 #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
  97 #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
  98 #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
  99 #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
 100 #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
 101
 102 #define _TP_EXDATA_PROTO0()                                             void *__tp_data
 103 #define _TP_EXDATA_PROTO2(a,b)                                          void *__tp_data,a b
 104 #define _TP_EXDATA_PROTO4(a,b,c,d)                                      void *__tp_data,a b,c d
 105 #define _TP_EXDATA_PROTO6(a,b,c,d,e,f)                                  void *__tp_data,a b,c d,e f
 106 #define _TP_EXDATA_PROTO8(a,b,c,d,e,f,g,h)                              void *__tp_data,a b,c d,e f,g h
 107 #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
 108 #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
 109 #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
 110 #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
 111 #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
 112 #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
 113
 114 /* Preprocessor trick to count arguments. Inspired from sdt.h. */
 115 #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)
 116 #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
 117 #define _TP_PROTO_N(N, ...)             _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXPROTO, N)(__VA_ARGS__))
 118 #define _TP_VAR_N(N, ...)               _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXVAR, N)(__VA_ARGS__))
 119 #define _TP_DATA_PROTO_N(N, ...)        _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXDATA_PROTO, N)(__VA_ARGS__))
 120 #define _TP_DATA_VAR_N(N, ...)          _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXDATA_VAR, N)(__VA_ARGS__))
 121 #define _TP_ARGS_PROTO(...)             _TP_PROTO_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
 122 #define _TP_ARGS_VAR(...)               _TP_VAR_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
 123 #define _TP_ARGS_DATA_PROTO(...)        _TP_DATA_PROTO_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
 124 #define _TP_ARGS_DATA_VAR(...)          _TP_DATA_VAR_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
 125 #define _TP_PARAMS(...)                 __VA_ARGS__
 126
 127 #define _DECLARE_TRACEPOINT(_provider, _name, ...)                                      \
 128 extern struct tracepoint __tracepoint_##_provider##___##_name;                          \
 129 static inline void __tracepoint_cb_##_provider##___##_name(_TP_ARGS_PROTO(__VA_ARGS__)) \
 130 {                                                                                       \
 131         struct tracepoint_probe *__tp_probe;                                            \
 132                                                                                         \
 133         if (!TP_RCU_LINK_TEST())                                                        \
 134                 return;                                                                 \
 135         tp_rcu_read_lock_bp();                                                          \
 136         __tp_probe = tp_rcu_dereference_bp(__tracepoint_##_provider##___##_name.probes); \
 137         if (caa_unlikely(!__tp_probe))                                                  \
 138                 goto end;                                                               \
 139         do {                                                                            \
 140                 void *__tp_cb = __tp_probe->func;                                       \
 141                 void *__tp_data = __tp_probe->data;                                     \
 142                                                                                         \
 143                 URCU_FORCE_CAST(void (*)(_TP_ARGS_DATA_PROTO(__VA_ARGS__)), __tp_cb)    \
 144                                 (_TP_ARGS_DATA_VAR(__VA_ARGS__));                       \
 145         } while ((++__tp_probe)->func);                                                 \
 146 end:                                                                                    \
 147         tp_rcu_read_unlock_bp();                                                        \
 148 }                                                                                       \
 149 static inline void __tracepoint_register_##_provider##___##_name(char *name,            \
 150                 void *func, void *data)                                                 \
 151 {                                                                                       \
 152         __tracepoint_probe_register(name, func, data,                                   \
 153                 __tracepoint_##_provider##___##_name.signature);                        \
 154 }                                                                                       \
 155 static inline void __tracepoint_unregister_##_provider##___##_name(char *name,          \
 156                 void *func, void *data)                                                 \
 157 {                                                                                       \
 158         __tracepoint_probe_unregister(name, func, data);                                \
 159 }
 160
 161 extern int __tracepoint_probe_register(const char *name, void *func, void *data,
 162                 const char *signature);
 163 extern int __tracepoint_probe_unregister(const char *name, void *func, void *data);
 164
 165 /*
 166  * tracepoint dynamic linkage handling (callbacks). Hidden visibility:
 167  * shared across objects in a module/main executable.
 168  */
 169 struct tracepoint_dlopen {
 170         void *liblttngust_handle;
 171
 172         int (*tracepoint_register_lib)(struct tracepoint * const *tracepoints_start,
 173                 int tracepoints_count);
 174         int (*tracepoint_unregister_lib)(struct tracepoint * const *tracepoints_start);
 175 #ifndef _LGPL_SOURCE
 176         void (*rcu_read_lock_sym_bp)(void);
 177         void (*rcu_read_unlock_sym_bp)(void);
 178         void *(*rcu_dereference_sym_bp)(void *p);
 179 #endif
 180 };
 181
 182 extern struct tracepoint_dlopen tracepoint_dlopen;
 183
 184 #ifdef TRACEPOINT_DEFINE
 185
 186 /*
 187  * When TRACEPOINT_PROBE_DYNAMIC_LINKAGE is defined, we do not emit a
 188  * unresolved symbol that requires the provider to be linked in. When
 189  * TRACEPOINT_PROBE_DYNAMIC_LINKAGE is not defined, we emit an
 190  * unresolved symbol that depends on having the provider linked in,
 191  * otherwise the linker complains. This deals with use of static
 192  * libraries, ensuring that the linker does not remove the provider
 193  * object from the executable.
 194  */
 195 #ifdef TRACEPOINT_PROBE_DYNAMIC_LINKAGE
 196 #define _TRACEPOINT_UNDEFINED_REF(provider)     NULL
 197 #else   /* TRACEPOINT_PROBE_DYNAMIC_LINKAGE */
 198 #define _TRACEPOINT_UNDEFINED_REF(provider)     &__tracepoint_provider_##provider
 199 #endif /* TRACEPOINT_PROBE_DYNAMIC_LINKAGE */
 200
 201 /*
 202  * Note: to allow PIC code, we need to allow the linker to update the pointers
 203  * in the __tracepoints_ptrs section.
 204  * Therefore, this section is _not_ const (read-only).
 205  */
 206 #define _TP_EXTRACT_STRING(...) #__VA_ARGS__
 207
 208 #define _DEFINE_TRACEPOINT(_provider, _name, _args)                             \
 209         extern int __tracepoint_provider_##_provider;                           \
 210         static const char __tp_strtab_##_provider##___##_name[]                 \
 211                 __attribute__((section("__tracepoints_strings"))) =             \
 212                         #_provider ":" #_name;                                  \
 213         struct tracepoint __tracepoint_##_provider##___##_name                  \
 214                 __attribute__((section("__tracepoints"))) =                     \
 215                 {                                                               \
 216                         __tp_strtab_##_provider##___##_name,                    \
 217                         0,                                                      \
 218                         NULL,                                                   \
 219                         _TRACEPOINT_UNDEFINED_REF(_provider),                   \
 220                         _TP_EXTRACT_STRING(_args),                              \
 221                 };                                                              \
 222         static struct tracepoint * __tracepoint_ptr_##_provider##___##_name     \
 223                 __attribute__((used, section("__tracepoints_ptrs"))) =          \
 224                         &__tracepoint_##_provider##___##_name;
 225
 226 /*
 227  * These weak symbols, the constructor, and destructor take care of
 228  * registering only _one_ instance of the tracepoints per shared-ojbect
 229  * (or for the whole main program).
 230  */
 231 extern struct tracepoint * const __start___tracepoints_ptrs[]
 232         __attribute__((weak, visibility("hidden")));
 233 extern struct tracepoint * const __stop___tracepoints_ptrs[]
 234         __attribute__((weak, visibility("hidden")));
 235 int __tracepoint_registered
 236         __attribute__((weak, visibility("hidden")));
 237 struct tracepoint_dlopen tracepoint_dlopen
 238         __attribute__((weak, visibility("hidden")));
 239
 240 static void __attribute__((constructor)) __tracepoints__init(void)
 241 {
 242         if (__tracepoint_registered++)
 243                 return;
 244
 245         tracepoint_dlopen.liblttngust_handle =
 246                 dlopen("liblttng-ust-tracepoint.so.0", RTLD_NOW | RTLD_GLOBAL);
 247         if (!tracepoint_dlopen.liblttngust_handle)
 248                 return;
 249         tracepoint_dlopen.tracepoint_register_lib =
 250                 URCU_FORCE_CAST(int (*)(struct tracepoint * const *, int),
 251                                 dlsym(tracepoint_dlopen.liblttngust_handle,
 252                                         "tracepoint_register_lib"));
 253         tracepoint_dlopen.tracepoint_unregister_lib =
 254                 URCU_FORCE_CAST(int (*)(struct tracepoint * const *),
 255                                 dlsym(tracepoint_dlopen.liblttngust_handle,
 256                                         "tracepoint_unregister_lib"));
 257 #ifndef _LGPL_SOURCE
 258         tracepoint_dlopen.rcu_read_lock_sym_bp =
 259                 URCU_FORCE_CAST(void (*)(void),
 260                                 dlsym(tracepoint_dlopen.liblttngust_handle,
 261                                         "tp_rcu_read_lock_bp"));
 262         tracepoint_dlopen.rcu_read_unlock_sym_bp =
 263                 URCU_FORCE_CAST(void (*)(void),
 264                                 dlsym(tracepoint_dlopen.liblttngust_handle,
 265                                         "tp_rcu_read_unlock_bp"));
 266         tracepoint_dlopen.rcu_dereference_sym_bp =
 267                 URCU_FORCE_CAST(void *(*)(void *p),
 268                                 dlsym(tracepoint_dlopen.liblttngust_handle,
 269                                         "tp_rcu_dereference_sym_bp"));
 270 #endif
 271         tracepoint_dlopen.tracepoint_register_lib(__start___tracepoints_ptrs,
 272                                 __stop___tracepoints_ptrs -
 273                                 __start___tracepoints_ptrs);
 274 }
 275
 276 static void __attribute__((destructor)) __tracepoints__destroy(void)
 277 {
 278         int ret;
 279
 280         if (--__tracepoint_registered)
 281                 return;
 282         if (tracepoint_dlopen.tracepoint_unregister_lib)
 283                 tracepoint_dlopen.tracepoint_unregister_lib(__start___tracepoints_ptrs);
 284         if (tracepoint_dlopen.liblttngust_handle) {
 285                 ret = dlclose(tracepoint_dlopen.liblttngust_handle);
 286                 assert(!ret);
 287                 memset(&tracepoint_dlopen, 0, sizeof(tracepoint_dlopen));
 288         }
 289 }
 290
 291 #else /* TRACEPOINT_DEFINE */
 292
 293 #define _DEFINE_TRACEPOINT(_provider, _name, _args)
 294
 295 #endif /* #else TRACEPOINT_DEFINE */
 296
 297 #ifdef __cplusplus
 298 }
 299 #endif
 300
 301 #endif /* _LTTNG_TRACEPOINT_H */
 302
 303 /* The following declarations must be outside re-inclusion protection. */
 304
 305 #ifndef TRACEPOINT_EVENT
 306
 307 /*
 308  * How to use the TRACEPOINT_EVENT macro:
 309  *
 310  * An example:
 311  *
 312  * TRACEPOINT_EVENT(someproject_component, event_name,
 313  *
 314  *     * TP_ARGS takes from 0 to 10 "type, field_name" pairs *
 315  *
 316  *     TP_ARGS(int, arg0, void *, arg1, char *, string, size_t, strlen,
 317  *             long *, arg4, size_t, arg4_len),
 318  *
 319  *      * TP_FIELDS describes the event payload layout in the trace *
 320  *
 321  *     TP_FIELDS(
 322  *         * Integer, printed in base 10 *
 323  *         ctf_integer(int, field_a, arg0)
 324  *
 325  *         * Integer, printed with 0x base 16 *
 326  *         ctf_integer_hex(unsigned long, field_d, arg1)
 327  *
 328  *         * Array Sequence, printed as UTF8-encoded array of bytes *
 329  *         ctf_array_text(char, field_b, string, FIXED_LEN)
 330  *         ctf_sequence_text(char, field_c, string, size_t, strlen)
 331  *
 332  *         * String, printed as UTF8-encoded string *
 333  *         ctf_string(field_e, string)
 334  *
 335  *         * Array sequence of signed integer values *
 336  *         ctf_array(long, field_f, arg4, FIXED_LEN4)
 337  *         ctf_sequence(long, field_g, arg4, size_t, arg4_len)
 338  *     )
 339  * )
 340  *
 341  * More detailed explanation:
 342  *
 343  * The name of the tracepoint is expressed as a tuple with the provider
 344  * and name arguments.
 345  *
 346  * The provider and name should be a proper C99 identifier.
 347  * The "provider" and "name" MUST follow these rules to ensure no
 348  * namespace clash occurs:
 349  *
 350  * For projects (applications and libraries) for which an entity
 351  * specific to the project controls the source code and thus its
 352  * tracepoints (typically with a scope larger than a single company):
 353  *
 354  * either:
 355  *   project_component, event
 356  * or:
 357  *   project, event
 358  *
 359  * Where "project" is the name of the project,
 360  *       "component" is the name of the project component (which may
 361  *       include several levels of sub-components, e.g.
 362  *       ...component_subcomponent_...) where the tracepoint is located
 363  *       (optional),
 364  *       "event" is the name of the tracepoint event.
 365  *
 366  * For projects issued from a single company wishing to advertise that
 367  * the company controls the source code and thus the tracepoints, the
 368  * "com_" prefix should be used:
 369  *
 370  * either:
 371  *   com_company_project_component, event
 372  * or:
 373  *   com_company_project, event
 374  *
 375  * Where "company" is the name of the company,
 376  *       "project" is the name of the project,
 377  *       "component" is the name of the project component (which may
 378  *       include several levels of sub-components, e.g.
 379  *       ...component_subcomponent_...) where the tracepoint is located
 380  *       (optional),
 381  *       "event" is the name of the tracepoint event.
 382  *
 383  * the provider:event identifier is limited to 127 characters.
 384  */
 385
 386 #define TRACEPOINT_EVENT(provider, name, args, fields)                  \
 387         _DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args))           \
 388         _DEFINE_TRACEPOINT(provider, name, _TP_PARAMS(args))
 389
 390 #define TRACEPOINT_EVENT_CLASS(provider, name, args, fields)
 391
 392 #define TRACEPOINT_EVENT_INSTANCE(provider, _template, name, args)      \
 393         _DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args))           \
 394         _DEFINE_TRACEPOINT(provider, name, _TP_PARAMS(args))
 395
 396 #endif /* #ifndef TRACEPOINT_EVENT */
 397
 398 #ifndef TRACEPOINT_LOGLEVEL
 399
 400 /*
 401  * Tracepoint Loglevels
 402  *
 403  * Typical use of these loglevels:
 404  *
 405  * The loglevels go from 0 to 14. Higher numbers imply the most
 406  * verbosity (higher event throughput expected.
 407  *
 408  * Loglevels 0 through 6, and loglevel 14, match syslog(3) loglevels
 409  * semantic. Loglevels 7 through 13 offer more fine-grained selection of
 410  * debug information.
 411  *
 412  * TRACE_EMERG           0
 413  * system is unusable
 414  *
 415  * TRACE_ALERT           1
 416  * action must be taken immediately
 417  *
 418  * TRACE_CRIT            2
 419  * critical conditions
 420  *
 421  * TRACE_ERR             3
 422  * error conditions
 423  *
 424  * TRACE_WARNING         4
 425  * warning conditions
 426  *
 427  * TRACE_NOTICE          5
 428  * normal, but significant, condition
 429  *
 430  * TRACE_INFO            6
 431  * informational message
 432  *
 433  * TRACE_DEBUG_SYSTEM    7
 434  * debug information with system-level scope (set of programs)
 435  *
 436  * TRACE_DEBUG_PROGRAM   8
 437  * debug information with program-level scope (set of processes)
 438  *
 439  * TRACE_DEBUG_PROCESS   9
 440  * debug information with process-level scope (set of modules)
 441  *
 442  * TRACE_DEBUG_MODULE    10
 443  * debug information with module (executable/library) scope (set of units)
 444  *
 445  * TRACE_DEBUG_UNIT      11
 446  * debug information with compilation unit scope (set of functions)
 447  *
 448  * TRACE_DEBUG_FUNCTION  12
 449  * debug information with function-level scope
 450  *
 451  * TRACE_DEBUG_LINE      13
 452  * debug information with line-level scope (TRACEPOINT_EVENT default)
 453  *
 454  * TRACE_DEBUG           14
 455  * debug-level message (trace_printf default)
 456  *
 457  * Declare tracepoint loglevels for tracepoints. A TRACEPOINT_EVENT
 458  * should be declared prior to the the TRACEPOINT_LOGLEVEL for a given
 459  * tracepoint name. The first field is the provider name, the second
 460  * field is the name of the tracepoint, the third field is the loglevel
 461  * name.
 462  *
 463  *      TRACEPOINT_LOGLEVEL(< [com_company_]project[_component] >, < event >,
 464  *              < loglevel_name >)
 465  *
 466  * The TRACEPOINT_PROVIDER must be already declared before declaring a
 467  * TRACEPOINT_LOGLEVEL.
 468  */
 469
 470 enum {
 471         TRACE_EMERG             = 0,
 472         TRACE_ALERT             = 1,
 473         TRACE_CRIT              = 2,
 474         TRACE_ERR               = 3,
 475         TRACE_WARNING           = 4,
 476         TRACE_NOTICE            = 5,
 477         TRACE_INFO              = 6,
 478         TRACE_DEBUG_SYSTEM      = 7,
 479         TRACE_DEBUG_PROGRAM     = 8,
 480         TRACE_DEBUG_PROCESS     = 9,
 481         TRACE_DEBUG_MODULE      = 10,
 482         TRACE_DEBUG_UNIT        = 11,
 483         TRACE_DEBUG_FUNCTION    = 12,
 484         TRACE_DEBUG_LINE        = 13,
 485         TRACE_DEBUG             = 14,
 486 };
 487
 488 #define TRACEPOINT_LOGLEVEL(provider, name, loglevel)
 489
 490 #endif /* #ifndef TRACEPOINT_LOGLEVEL */