include/lttng/tracepoint.h

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   5  */
   6
   7 #ifndef _LTTNG_UST_TRACEPOINT_H
   8 #define _LTTNG_UST_TRACEPOINT_H
   9
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <lttng/tracepoint-types.h>
  13 #include <lttng/tracepoint-rcu.h>
  14 #include <lttng/ust-utils.h>
  15 #include <sys/types.h>
  16 #include <unistd.h>
  17
  18 #include <urcu/compiler.h>
  19 #include <urcu/system.h>
  20 #include <dlfcn.h>      /* for dlopen */
  21 #include <string.h>     /* for memset */
  22 #include <stdbool.h>
  23
  24 #include <lttng/ust-config.h>   /* for sdt */
  25 #include <lttng/ust-compiler.h>
  26 #include <lttng/ust-tracer.h>
  27 #include <lttng/ust-api-compat.h>
  28
  29 #define LTTNG_UST_TRACEPOINT_NAME_LEN_MAX       256
  30
  31 #ifdef LTTNG_UST_HAVE_SDT_INTEGRATION
  32 /*
  33  * Instead of using SDT_USE_VARIADIC from 'sys/sdt.h', use our own namespaced
  34  * macros since the instrumented application might already have included
  35  * 'sys/sdt.h' without variadic support.
  36  */
  37 #include <sys/sdt.h>
  38
  39 #define LTTNG_UST__SDT_NARG(...) \
  40         LTTNG_UST___SDT_NARG(__VA_ARGS__, 12,11,10,9,8,7,6,5,4,3,2,1,0)
  41
  42 #define LTTNG_UST___SDT_NARG(_0,_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,_11,_12, N, ...) N
  43
  44 #define LTTNG_UST__SDT_PROBE_N(provider, name, N, ...) \
  45         _SDT_PROBE(provider, name, N, (__VA_ARGS__))
  46
  47 #define LTTNG_UST_STAP_PROBEV(provider, name, ...) \
  48         LTTNG_UST__SDT_PROBE_N(provider, name, LTTNG_UST__SDT_NARG(0, ##__VA_ARGS__), ##__VA_ARGS__)
  49
  50 #else
  51 #define LTTNG_UST_STAP_PROBEV(...)
  52 #endif
  53
  54 #ifdef __cplusplus
  55 extern "C" {
  56 #endif
  57
  58 #define lttng_ust_tracepoint_enabled(provider, name)                            \
  59         caa_unlikely(CMM_LOAD_SHARED(lttng_ust_tracepoint_##provider##___##name.state))
  60
  61 #define lttng_ust_do_tracepoint(provider, name, ...)                            \
  62         lttng_ust_tracepoint_cb_##provider##___##name(__VA_ARGS__)
  63
  64 #define lttng_ust_tracepoint(provider, name, ...)                               \
  65         do {                                                                    \
  66                 LTTNG_UST_STAP_PROBEV(provider, name, ## __VA_ARGS__);          \
  67                 if (lttng_ust_tracepoint_enabled(provider, name))               \
  68                         lttng_ust_do_tracepoint(provider, name, __VA_ARGS__);   \
  69         } while (0)
  70
  71 #define LTTNG_UST_TP_ARGS(...)       __VA_ARGS__
  72
  73 /*
  74  * LTTNG_UST_TP_ARGS takes tuples of type, argument separated by a comma.
  75  * It can take up to 10 tuples (which means that less than 10 tuples is
  76  * fine too).
  77  * Each tuple is also separated by a comma.
  78  */
  79 #define LTTNG_UST___TP_COMBINE_TOKENS(_tokena, _tokenb)                         \
  80                 _tokena##_tokenb
  81 #define LTTNG_UST__TP_COMBINE_TOKENS(_tokena, _tokenb)                          \
  82                 LTTNG_UST___TP_COMBINE_TOKENS(_tokena, _tokenb)
  83 #define LTTNG_UST___TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc)                       \
  84                 _tokena##_tokenb##_tokenc
  85 #define LTTNG_UST__TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc)                        \
  86                 LTTNG_UST___TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc)
  87 #define LTTNG_UST___TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend)      \
  88                 _tokena##_tokenb##_tokenc##_tokend
  89 #define LTTNG_UST__TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend)               \
  90                 LTTNG_UST___TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend)
  91
  92 /*
  93  * LTTNG_UST__TP_EXVAR* extract the var names.
  94  * LTTNG_UST__TP_EXVAR1 and LTTNG_UST__TP_EXDATA_VAR1 are needed for -std=c99.
  95  */
  96 #define LTTNG_UST__TP_EXVAR0()
  97 #define LTTNG_UST__TP_EXVAR1(a)
  98 #define LTTNG_UST__TP_EXVAR2(a,b)                                               b
  99 #define LTTNG_UST__TP_EXVAR4(a,b,c,d)                                   b,d
 100 #define LTTNG_UST__TP_EXVAR6(a,b,c,d,e,f)                                       b,d,f
 101 #define LTTNG_UST__TP_EXVAR8(a,b,c,d,e,f,g,h)                           b,d,f,h
 102 #define LTTNG_UST__TP_EXVAR10(a,b,c,d,e,f,g,h,i,j)                      b,d,f,h,j
 103 #define LTTNG_UST__TP_EXVAR12(a,b,c,d,e,f,g,h,i,j,k,l)                  b,d,f,h,j,l
 104 #define LTTNG_UST__TP_EXVAR14(a,b,c,d,e,f,g,h,i,j,k,l,m,n)              b,d,f,h,j,l,n
 105 #define LTTNG_UST__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
 106 #define LTTNG_UST__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
 107 #define LTTNG_UST__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
 108
 109 #define LTTNG_UST__TP_EXDATA_VAR0()                                             __tp_data
 110 #define LTTNG_UST__TP_EXDATA_VAR1(a)                                            __tp_data
 111 #define LTTNG_UST__TP_EXDATA_VAR2(a,b)                                          __tp_data,b
 112 #define LTTNG_UST__TP_EXDATA_VAR4(a,b,c,d)                                      __tp_data,b,d
 113 #define LTTNG_UST__TP_EXDATA_VAR6(a,b,c,d,e,f)                                  __tp_data,b,d,f
 114 #define LTTNG_UST__TP_EXDATA_VAR8(a,b,c,d,e,f,g,h)                              __tp_data,b,d,f,h
 115 #define LTTNG_UST__TP_EXDATA_VAR10(a,b,c,d,e,f,g,h,i,j)                         __tp_data,b,d,f,h,j
 116 #define LTTNG_UST__TP_EXDATA_VAR12(a,b,c,d,e,f,g,h,i,j,k,l)                     __tp_data,b,d,f,h,j,l
 117 #define LTTNG_UST__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
 118 #define LTTNG_UST__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
 119 #define LTTNG_UST__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
 120 #define LTTNG_UST__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
 121
 122 /*
 123  * LTTNG_UST__TP_EXPROTO* extract tuples of type, var.
 124  * LTTNG_UST__TP_EXPROTO1 and LTTNG_UST__TP_EXDATA_PROTO1 are needed for -std=c99.
 125  */
 126 #define LTTNG_UST__TP_EXPROTO0()                                                void
 127 #define LTTNG_UST__TP_EXPROTO1(a)                                               void
 128 #define LTTNG_UST__TP_EXPROTO2(a,b)                                     a b
 129 #define LTTNG_UST__TP_EXPROTO4(a,b,c,d)                                 a b,c d
 130 #define LTTNG_UST__TP_EXPROTO6(a,b,c,d,e,f)                             a b,c d,e f
 131 #define LTTNG_UST__TP_EXPROTO8(a,b,c,d,e,f,g,h)                         a b,c d,e f,g h
 132 #define LTTNG_UST__TP_EXPROTO10(a,b,c,d,e,f,g,h,i,j)                    a b,c d,e f,g h,i j
 133 #define LTTNG_UST__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
 134 #define LTTNG_UST__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
 135 #define LTTNG_UST__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
 136 #define LTTNG_UST__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
 137 #define LTTNG_UST__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
 138
 139 #define LTTNG_UST__TP_EXDATA_PROTO0()                                           void *__tp_data
 140 #define LTTNG_UST__TP_EXDATA_PROTO1(a)                                          void *__tp_data
 141 #define LTTNG_UST__TP_EXDATA_PROTO2(a,b)                                                void *__tp_data,a b
 142 #define LTTNG_UST__TP_EXDATA_PROTO4(a,b,c,d)                                    void *__tp_data,a b,c d
 143 #define LTTNG_UST__TP_EXDATA_PROTO6(a,b,c,d,e,f)                                        void *__tp_data,a b,c d,e f
 144 #define LTTNG_UST__TP_EXDATA_PROTO8(a,b,c,d,e,f,g,h)                            void *__tp_data,a b,c d,e f,g h
 145 #define LTTNG_UST__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
 146 #define LTTNG_UST__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
 147 #define LTTNG_UST__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
 148 #define LTTNG_UST__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
 149 #define LTTNG_UST__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
 150 #define LTTNG_UST__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
 151
 152 /* Preprocessor trick to count arguments. Inspired from sdt.h. */
 153 #define LTTNG_UST__TP_NARGS(...)                LTTNG_UST___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)
 154 #define LTTNG_UST___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
 155 #define LTTNG_UST__TP_PROTO_N(N, ...)           LTTNG_UST__TP_PARAMS(LTTNG_UST__TP_COMBINE_TOKENS(LTTNG_UST__TP_EXPROTO, N)(__VA_ARGS__))
 156 #define LTTNG_UST__TP_VAR_N(N, ...)             LTTNG_UST__TP_PARAMS(LTTNG_UST__TP_COMBINE_TOKENS(LTTNG_UST__TP_EXVAR, N)(__VA_ARGS__))
 157 #define LTTNG_UST__TP_DATA_PROTO_N(N, ...)      LTTNG_UST__TP_PARAMS(LTTNG_UST__TP_COMBINE_TOKENS(LTTNG_UST__TP_EXDATA_PROTO, N)(__VA_ARGS__))
 158 #define LTTNG_UST__TP_DATA_VAR_N(N, ...)        LTTNG_UST__TP_PARAMS(LTTNG_UST__TP_COMBINE_TOKENS(LTTNG_UST__TP_EXDATA_VAR, N)(__VA_ARGS__))
 159 #define LTTNG_UST__TP_ARGS_PROTO(...)           LTTNG_UST__TP_PROTO_N(LTTNG_UST__TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
 160 #define LTTNG_UST__TP_ARGS_VAR(...)             LTTNG_UST__TP_VAR_N(LTTNG_UST__TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
 161 #define LTTNG_UST__TP_ARGS_DATA_PROTO(...)      LTTNG_UST__TP_DATA_PROTO_N(LTTNG_UST__TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
 162 #define LTTNG_UST__TP_ARGS_DATA_VAR(...)        LTTNG_UST__TP_DATA_VAR_N(LTTNG_UST__TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
 163 #define LTTNG_UST__TP_PARAMS(...)               __VA_ARGS__
 164
 165 /*
 166  * sizeof(#_provider) - 1 : length of the provider string (excluding \0).
 167  * sizeof(#_name) - 1     : length of the name string (excluding \0).
 168  * + 1                    : separator between provider and event name.
 169  *
 170  * Upper bound (inclusive) is LTTNG_UST_TRACEPOINT_NAME_LEN_MAX - 1 to
 171  * account for \0.
 172  *
 173  * The comparison is:
 174  *   left hand side:   sizeof(#_provider) - 1 + sizeof(#_name) - 1 + 1
 175  *   right hand side:  LTTNG_UST_TRACEPOINT_NAME_LEN_MAX - 1
 176  *   operator:         <=  (inclusive)
 177  * Simplified in the code below.
 178  */
 179 #define lttng_ust_tracepoint_validate_name_len(_provider, _name)                                                \
 180         lttng_ust_static_assert(sizeof(#_provider) + sizeof(#_name) <= LTTNG_UST_TRACEPOINT_NAME_LEN_MAX,       \
 181                 "Tracepoint name length is too long",                                                           \
 182                 Tracepoint_name_length_is_too_long)
 183
 184 /*
 185  * The tracepoint cb is marked always inline so we can distinguish
 186  * between caller's ip addresses within the probe using the return
 187  * address.
 188  */
 189 #define LTTNG_UST__DECLARE_TRACEPOINT(_provider, _name, ...)                                    \
 190 extern struct lttng_ust_tracepoint lttng_ust_tracepoint_##_provider##___##_name         \
 191                 LTTNG_UST__TRACEPOINT_DEFINITION_VISIBILITY;                            \
 192 static inline                                                                           \
 193 void lttng_ust_tracepoint_cb_##_provider##___##_name(LTTNG_UST__TP_ARGS_PROTO(__VA_ARGS__))             \
 194         __attribute__((always_inline, unused)) lttng_ust_notrace;                       \
 195 static                                                                                  \
 196 void lttng_ust_tracepoint_cb_##_provider##___##_name(LTTNG_UST__TP_ARGS_PROTO(__VA_ARGS__))             \
 197 {                                                                                       \
 198         struct lttng_ust_tracepoint_probe *__tp_probe;                                  \
 199                                                                                         \
 200         if (caa_unlikely(!LTTNG_UST_TP_RCU_LINK_TEST()))                                                \
 201                 return;                                                                 \
 202         lttng_ust_tp_rcu_read_lock();                                                           \
 203         __tp_probe = lttng_ust_tp_rcu_dereference(lttng_ust_tracepoint_##_provider##___##_name.probes); \
 204         if (caa_unlikely(!__tp_probe))                                                  \
 205                 goto end;                                                               \
 206         do {                                                                            \
 207                 void (*__tp_cb)(void) = __tp_probe->func;                               \
 208                 void *__tp_data = __tp_probe->data;                                     \
 209                                                                                         \
 210                 URCU_FORCE_CAST(void (*)(LTTNG_UST__TP_ARGS_DATA_PROTO(__VA_ARGS__)), __tp_cb)  \
 211                                 (LTTNG_UST__TP_ARGS_DATA_VAR(__VA_ARGS__));                     \
 212         } while ((++__tp_probe)->func);                                                 \
 213 end:                                                                                    \
 214         lttng_ust_tp_rcu_read_unlock();                                                         \
 215 }                                                                                       \
 216 static inline                                                                           \
 217 void lttng_ust_tracepoint_register_##_provider##___##_name(char *provider_name, char *event_name, \
 218                 void (*func)(void), void *data)                                         \
 219         lttng_ust_notrace;                                                              \
 220 static inline                                                                           \
 221 void lttng_ust_tracepoint_register_##_provider##___##_name(char *provider_name, char *event_name, \
 222                 void (*func)(void), void *data)                                         \
 223 {                                                                                       \
 224         lttng_ust_tracepoint_provider_register(provider_name, event_name, func, data,           \
 225                 lttng_ust_tracepoint_##_provider##___##_name.signature);                        \
 226 }                                                                                       \
 227 static inline                                                                           \
 228 void lttng_ust_tracepoint_unregister_##_provider##___##_name(char *provider_name, char *event_name, \
 229                 void (*func)(void), void *data)                                         \
 230         lttng_ust_notrace;                                                              \
 231 static inline                                                                           \
 232 void lttng_ust_tracepoint_unregister_##_provider##___##_name(char *provider_name, char *event_name, \
 233                 void (*func)(void), void *data)                                         \
 234 {                                                                                       \
 235         lttng_ust_tracepoint_provider_unregister(provider_name, event_name, func, data);                \
 236 }
 237
 238 /*
 239  * Registration of tracepoint provider probe functions with
 240  * lttng_ust_tracepoint_provider_register, unregistration with
 241  * lttng_ust_tracepoint_provider_unregister.
 242  */
 243 int lttng_ust_tracepoint_provider_register(const char *provider_name, const char *event_name,
 244                 void (*func)(void), void *data, const char *signature);
 245 int lttng_ust_tracepoint_provider_unregister(const char *provider_name, const char *event_name,
 246                 void (*func)(void), void *data);
 247
 248 /*
 249  * Registration of tracepoint instrumentation modules with lttng_ust_tracepoint_module_register,
 250  * unregistration with lttng_ust_tracepoint_module_unregister.
 251  */
 252 int lttng_ust_tracepoint_module_register(struct lttng_ust_tracepoint * const *tracepoints_start,
 253                              int tracepoints_count);
 254 int lttng_ust_tracepoint_module_unregister(struct lttng_ust_tracepoint * const *tracepoints_start);
 255
 256 /*
 257  * tracepoint dynamic linkage handling (callbacks). Hidden visibility:
 258  * shared across objects in a module/main executable.
 259  *
 260  * IMPORTANT: this structure is part of the ABI between instrumented
 261  * applications and UST. Fields need to be only added at the end, never
 262  * reordered, never removed.
 263  *
 264  * The field @struct_size should be used to determine the size of the
 265  * structure. It should be queried before using additional fields added
 266  * at the end of the structure.
 267  */
 268 struct lttng_ust_tracepoint_dlopen {
 269         uint32_t struct_size;
 270
 271         void *liblttngust_handle;
 272
 273         int (*lttng_ust_tracepoint_module_register)(struct lttng_ust_tracepoint * const *tracepoints_start,
 274                 int tracepoints_count);
 275         int (*lttng_ust_tracepoint_module_unregister)(struct lttng_ust_tracepoint * const *tracepoints_start);
 276         void (*rcu_read_lock_sym)(void);
 277         void (*rcu_read_unlock_sym)(void);
 278         void *(*rcu_dereference_sym)(void *p);
 279
 280         /* End of base ABI. Fields below should be used after checking struct_size. */
 281 };
 282
 283 extern struct lttng_ust_tracepoint_dlopen lttng_ust_tracepoint_dlopen;
 284 extern struct lttng_ust_tracepoint_dlopen *lttng_ust_tracepoint_dlopen_ptr;
 285
 286 /*
 287  * These weak symbols, the constructor, and destructor take care of
 288  * registering only _one_ instance of the tracepoints per shared-ojbect
 289  * (or for the whole main program).
 290  */
 291 int lttng_ust_tracepoint_registered
 292         __attribute__((weak, visibility("hidden")));
 293 int lttng_ust_tracepoint_ptrs_registered
 294         __attribute__((weak, visibility("hidden")));
 295 struct lttng_ust_tracepoint_dlopen lttng_ust_tracepoint_dlopen
 296                 __attribute__((weak, visibility("hidden"))) = {
 297         .struct_size = sizeof(struct lttng_ust_tracepoint_dlopen),
 298 };
 299 /*
 300  * Deal with gcc O1 optimisation issues with weak hidden symbols. gcc
 301  * 4.8 and prior does not have the same behavior for symbol scoping on
 302  * 32-bit powerpc depending on the object size: symbols for objects of 8
 303  * bytes or less have the same address throughout a module, whereas they
 304  * have different addresses between compile units for objects larger
 305  * than 8 bytes. Add this pointer indirection to ensure that the symbol
 306  * scoping match that of the other weak hidden symbols found in this
 307  * header.
 308  */
 309 struct lttng_ust_tracepoint_dlopen *lttng_ust_tracepoint_dlopen_ptr
 310         __attribute__((weak, visibility("hidden")));
 311
 312 /*
 313  * Tracepoint dynamic linkage handling (callbacks). Hidden visibility: shared
 314  * across objects in a module/main executable. The callbacks are used to
 315  * control and check if the destructors should be executed.
 316  *
 317  * IMPORTANT: this structure is part of the ABI between instrumented
 318  * applications and UST. Fields need to be only added at the end, never
 319  * reordered, never removed.
 320  *
 321  * The field @struct_size should be used to determine the size of the
 322  * structure. It should be queried before using additional fields added
 323  * at the end of the structure.
 324  */
 325 struct lttng_ust_tracepoint_destructors_syms {
 326         uint32_t struct_size;
 327
 328         void (*tracepoint_disable_destructors)(void);
 329         int (*tracepoint_get_destructors_state)(void);
 330
 331         /* End of base ABI. Fields below should be used after checking struct_size. */
 332 };
 333
 334 extern struct lttng_ust_tracepoint_destructors_syms lttng_ust_tracepoint_destructors_syms;
 335 extern struct lttng_ust_tracepoint_destructors_syms *lttng_ust_tracepoint_destructors_syms_ptr;
 336
 337 struct lttng_ust_tracepoint_destructors_syms lttng_ust_tracepoint_destructors_syms
 338         __attribute__((weak, visibility("hidden"))) = {
 339         .struct_size = sizeof(struct lttng_ust_tracepoint_destructors_syms),
 340 };
 341 struct lttng_ust_tracepoint_destructors_syms *lttng_ust_tracepoint_destructors_syms_ptr
 342         __attribute__((weak, visibility("hidden")));
 343
 344 static inline void tracepoint_disable_destructors(void)
 345 {
 346         if (!lttng_ust_tracepoint_dlopen_ptr)
 347                 lttng_ust_tracepoint_dlopen_ptr = &lttng_ust_tracepoint_dlopen;
 348         if (!lttng_ust_tracepoint_destructors_syms_ptr)
 349                 lttng_ust_tracepoint_destructors_syms_ptr = &lttng_ust_tracepoint_destructors_syms;
 350         if (lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle
 351                         && lttng_ust_tracepoint_destructors_syms_ptr->tracepoint_disable_destructors)
 352                 lttng_ust_tracepoint_destructors_syms_ptr->tracepoint_disable_destructors();
 353 }
 354
 355 #ifndef _LGPL_SOURCE
 356 static inline void
 357 lttng_ust_tracepoint__init_urcu_sym(void)
 358         lttng_ust_notrace;
 359 static inline void
 360 lttng_ust_tracepoint__init_urcu_sym(void)
 361 {
 362         if (!lttng_ust_tracepoint_dlopen_ptr)
 363                 lttng_ust_tracepoint_dlopen_ptr = &lttng_ust_tracepoint_dlopen;
 364         /*
 365          * Symbols below are needed by tracepoint call sites and probe
 366          * providers.
 367          */
 368         if (!lttng_ust_tracepoint_dlopen_ptr->rcu_read_lock_sym)
 369                 lttng_ust_tracepoint_dlopen_ptr->rcu_read_lock_sym =
 370                         URCU_FORCE_CAST(void (*)(void),
 371                                 dlsym(lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle,
 372                                         "lttng_ust_tp_rcu_read_lock"));
 373         if (!lttng_ust_tracepoint_dlopen_ptr->rcu_read_unlock_sym)
 374                 lttng_ust_tracepoint_dlopen_ptr->rcu_read_unlock_sym =
 375                         URCU_FORCE_CAST(void (*)(void),
 376                                 dlsym(lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle,
 377                                         "lttng_ust_tp_rcu_read_unlock"));
 378         if (!lttng_ust_tracepoint_dlopen_ptr->rcu_dereference_sym)
 379                 lttng_ust_tracepoint_dlopen_ptr->rcu_dereference_sym =
 380                         URCU_FORCE_CAST(void *(*)(void *p),
 381                                 dlsym(lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle,
 382                                         "lttng_ust_tp_rcu_dereference_sym"));
 383 }
 384 #else
 385 static inline void
 386 lttng_ust_tracepoint__init_urcu_sym(void)
 387         lttng_ust_notrace;
 388 static inline void
 389 lttng_ust_tracepoint__init_urcu_sym(void)
 390 {
 391 }
 392 #endif
 393
 394 /*
 395  * Use getenv() directly and bypass lttng-ust helper functions
 396  * because we may not have access to lttng-ust shared libraries.
 397  */
 398 #ifdef LTTNG_UST_DEBUG
 399 static inline
 400 bool lttng_ust_tracepoint_logging_debug_enabled(void)
 401 {
 402         return true;
 403 }
 404 #else /* #ifdef LTTNG_UST_DEBUG */
 405 static inline
 406 bool lttng_ust_tracepoint_logging_debug_enabled(void)
 407 {
 408         return getenv("LTTNG_UST_DEBUG");
 409 }
 410 #endif /* #ifdef LTTNG_UST_DEBUG */
 411
 412 #define LTTNG_UST_TRACEPOINT_THIS_IP            \
 413         ({ __label__ here; here: &&here; })
 414
 415 static void
 416 lttng_ust_tracepoints_print_disabled_message(void)
 417 {
 418         if (!lttng_ust_tracepoint_logging_debug_enabled())
 419                 return;
 420         fprintf(stderr, "lttng-ust-tracepoint [%ld]: dlopen() failed to find '%s', tracepoints in this binary won't be registered. "
 421                 "(at addr=%p in %s() at " __FILE__ ":" lttng_ust_stringify(__LINE__) ")\n",
 422                 (long) getpid(),
 423                 LTTNG_UST_TRACEPOINT_LIB_SONAME,
 424                 LTTNG_UST_TRACEPOINT_THIS_IP,
 425                 __func__);
 426 }
 427
 428 static void
 429 lttng_ust__tracepoints__init(void)
 430         lttng_ust_notrace __attribute__((constructor));
 431 static void
 432 lttng_ust__tracepoints__init(void)
 433 {
 434         if (lttng_ust_tracepoint_registered++) {
 435                 if (!lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle)
 436                         return;
 437                 lttng_ust_tracepoint__init_urcu_sym();
 438                 return;
 439         }
 440
 441         if (!lttng_ust_tracepoint_dlopen_ptr)
 442                 lttng_ust_tracepoint_dlopen_ptr = &lttng_ust_tracepoint_dlopen;
 443         if (!lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle)
 444                 lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle =
 445                         dlopen(LTTNG_UST_TRACEPOINT_LIB_SONAME, RTLD_NOW | RTLD_GLOBAL);
 446         if (!lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle) {
 447                 lttng_ust_tracepoints_print_disabled_message();
 448                 return;
 449         }
 450         lttng_ust_tracepoint__init_urcu_sym();
 451 }
 452
 453 static void
 454 lttng_ust__tracepoints__destroy(void)
 455         lttng_ust_notrace __attribute__((destructor));
 456 static void
 457 lttng_ust__tracepoints__destroy(void)
 458 {
 459         int ret;
 460
 461         if (--lttng_ust_tracepoint_registered)
 462                 return;
 463         if (!lttng_ust_tracepoint_dlopen_ptr)
 464                 lttng_ust_tracepoint_dlopen_ptr = &lttng_ust_tracepoint_dlopen;
 465         if (!lttng_ust_tracepoint_destructors_syms_ptr)
 466                 lttng_ust_tracepoint_destructors_syms_ptr = &lttng_ust_tracepoint_destructors_syms;
 467         if (!lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle)
 468                 return;
 469         if (lttng_ust_tracepoint_ptrs_registered)
 470                 return;
 471         /*
 472          * Lookup if destructors must be executed using the new method.
 473          */
 474         if (lttng_ust_tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state
 475                 && !lttng_ust_tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state()) {
 476                 /*
 477                  * The tracepoint_get_destructors_state symbol was found with
 478                  * dlsym but its returned value is 0 meaning that destructors
 479                  * must not be executed.
 480                  */
 481                 return;
 482         }
 483         ret = dlclose(lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle);
 484         if (ret) {
 485                 fprintf(stderr, "Error (%d) in dlclose\n", ret);
 486                 abort();
 487         }
 488         memset(lttng_ust_tracepoint_dlopen_ptr, 0, sizeof(*lttng_ust_tracepoint_dlopen_ptr));
 489 }
 490
 491 #if LTTNG_UST_COMPAT_API(0)
 492 # if defined(TRACEPOINT_DEFINE) && !defined(LTTNG_UST_TRACEPOINT_DEFINE)
 493 #  define LTTNG_UST_TRACEPOINT_DEFINE
 494 # endif
 495 #endif /* #if LTTNG_UST_COMPAT_API(0) */
 496
 497 #ifdef LTTNG_UST_TRACEPOINT_DEFINE
 498
 499 /*
 500  * These weak symbols, the constructor, and destructor take care of
 501  * registering only _one_ instance of the tracepoints per shared-ojbect
 502  * (or for the whole main program).
 503  */
 504 extern struct lttng_ust_tracepoint * const __start_lttng_ust_tracepoints_ptrs[]
 505         __attribute__((weak, visibility("hidden")));
 506 extern struct lttng_ust_tracepoint * const __stop_lttng_ust_tracepoints_ptrs[]
 507         __attribute__((weak, visibility("hidden")));
 508
 509 /*
 510  * When LTTNG_UST_TRACEPOINT_PROBE_DYNAMIC_LINKAGE is defined, we do not emit a
 511  * unresolved symbol that requires the provider to be linked in. When
 512  * LTTNG_UST_TRACEPOINT_PROBE_DYNAMIC_LINKAGE is not defined, we emit an
 513  * unresolved symbol that depends on having the provider linked in,
 514  * otherwise the linker complains. This deals with use of static
 515  * libraries, ensuring that the linker does not remove the provider
 516  * object from the executable.
 517  */
 518
 519 #if LTTNG_UST_COMPAT_API(0)
 520 # if defined(TRACEPOINT_PROBE_DYNAMIC_LINKAGE) && !defined(LTTNG_UST_TRACEPOINT_PROBE_DYNAMIC_LINKAGE)
 521 #  define LTTNG_UST_TRACEPOINT_PROBE_DYNAMIC_LINKAGE
 522 # endif
 523 #endif /* #if LTTNG_UST_COMPAT_API(0) */
 524
 525 #ifdef LTTNG_UST_TRACEPOINT_PROBE_DYNAMIC_LINKAGE
 526 #define LTTNG_UST__TRACEPOINT_UNDEFINED_REF(provider)   NULL
 527 #else   /* LTTNG_UST_TRACEPOINT_PROBE_DYNAMIC_LINKAGE */
 528 #define LTTNG_UST__TRACEPOINT_UNDEFINED_REF(provider)   &lttng_ust_tracepoint_provider_##provider
 529 #endif /* LTTNG_UST_TRACEPOINT_PROBE_DYNAMIC_LINKAGE */
 530
 531 /*
 532  * Note: to allow PIC code, we need to allow the linker to update the pointers
 533  * in the lttng_ust_tracepoints_ptrs section.
 534  * Therefore, this section is _not_ const (read-only).
 535  */
 536 #define LTTNG_UST__TP_EXTRACT_STRING(...)       #__VA_ARGS__
 537
 538 #define LTTNG_UST__DEFINE_TRACEPOINT(_provider, _name, _args)                           \
 539         lttng_ust_tracepoint_validate_name_len(_provider, _name);               \
 540         extern int lttng_ust_tracepoint_provider_##_provider                    \
 541                 LTTNG_UST__TRACEPOINT_PROVIDER_DEFINITION_VISIBILITY;           \
 542         static const char lttng_ust_tp_provider_strtab_##_provider##___##_name[]        \
 543                 __attribute__((section("lttng_ust_tracepoints_strings"))) =             \
 544                         #_provider;                                             \
 545         static const char lttng_ust_tp_name_strtab_##_provider##___##_name[]            \
 546                 __attribute__((section("lttng_ust_tracepoints_strings"))) =             \
 547                         #_name;                                                 \
 548         struct lttng_ust_tracepoint lttng_ust_tracepoint_##_provider##___##_name        \
 549                 __attribute__((section("lttng_ust_tracepoints")))               \
 550                 LTTNG_UST__TRACEPOINT_DEFINITION_VISIBILITY = {                 \
 551                         sizeof(struct lttng_ust_tracepoint),                    \
 552                         lttng_ust_tp_provider_strtab_##_provider##___##_name,           \
 553                         lttng_ust_tp_name_strtab_##_provider##___##_name,               \
 554                         0,                                                      \
 555                         NULL,                                                   \
 556                         LTTNG_UST__TRACEPOINT_UNDEFINED_REF(_provider),         \
 557                         LTTNG_UST__TP_EXTRACT_STRING(_args),                    \
 558                 };                                                              \
 559         static struct lttng_ust_tracepoint *                                    \
 560                 lttng_ust_tracepoint_ptr_##_provider##___##_name                        \
 561                 __attribute__((section("lttng_ust_tracepoints_ptrs"), used))            \
 562                 __lttng_ust_variable_attribute_no_sanitize_address =            \
 563                         &lttng_ust_tracepoint_##_provider##___##_name;
 564
 565 static void
 566 lttng_ust__tracepoints__ptrs_init(void)
 567         lttng_ust_notrace __attribute__((constructor));
 568 static void
 569 lttng_ust__tracepoints__ptrs_init(void)
 570 {
 571         if (lttng_ust_tracepoint_ptrs_registered++)
 572                 return;
 573         if (!lttng_ust_tracepoint_dlopen_ptr)
 574                 lttng_ust_tracepoint_dlopen_ptr = &lttng_ust_tracepoint_dlopen;
 575         if (!lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle)
 576                 lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle =
 577                         dlopen(LTTNG_UST_TRACEPOINT_LIB_SONAME, RTLD_NOW | RTLD_GLOBAL);
 578         if (!lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle) {
 579                 lttng_ust_tracepoints_print_disabled_message();
 580                 return;
 581         }
 582         if (!lttng_ust_tracepoint_destructors_syms_ptr)
 583                 lttng_ust_tracepoint_destructors_syms_ptr = &lttng_ust_tracepoint_destructors_syms;
 584         lttng_ust_tracepoint_dlopen_ptr->lttng_ust_tracepoint_module_register =
 585                 URCU_FORCE_CAST(int (*)(struct lttng_ust_tracepoint * const *, int),
 586                                 dlsym(lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle,
 587                                         "lttng_ust_tracepoint_module_register"));
 588         lttng_ust_tracepoint_dlopen_ptr->lttng_ust_tracepoint_module_unregister =
 589                 URCU_FORCE_CAST(int (*)(struct lttng_ust_tracepoint * const *),
 590                                 dlsym(lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle,
 591                                         "lttng_ust_tracepoint_module_unregister"));
 592         lttng_ust_tracepoint_destructors_syms_ptr->tracepoint_disable_destructors =
 593                 URCU_FORCE_CAST(void (*)(void),
 594                                 dlsym(lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle,
 595                                         "lttng_ust_tp_disable_destructors"));
 596         lttng_ust_tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state =
 597                 URCU_FORCE_CAST(int (*)(void),
 598                                 dlsym(lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle,
 599                                         "lttng_ust_tp_get_destructors_state"));
 600         lttng_ust_tracepoint__init_urcu_sym();
 601         if (lttng_ust_tracepoint_dlopen_ptr->lttng_ust_tracepoint_module_register) {
 602                 lttng_ust_tracepoint_dlopen_ptr->lttng_ust_tracepoint_module_register(__start_lttng_ust_tracepoints_ptrs,
 603                                 __stop_lttng_ust_tracepoints_ptrs -
 604                                 __start_lttng_ust_tracepoints_ptrs);
 605         }
 606 }
 607
 608 static void
 609 lttng_ust__tracepoints__ptrs_destroy(void)
 610         lttng_ust_notrace __attribute__((destructor));
 611 static void
 612 lttng_ust__tracepoints__ptrs_destroy(void)
 613 {
 614         int ret;
 615
 616         if (--lttng_ust_tracepoint_ptrs_registered)
 617                 return;
 618         if (!lttng_ust_tracepoint_dlopen_ptr)
 619                 lttng_ust_tracepoint_dlopen_ptr = &lttng_ust_tracepoint_dlopen;
 620         if (!lttng_ust_tracepoint_destructors_syms_ptr)
 621                 lttng_ust_tracepoint_destructors_syms_ptr = &lttng_ust_tracepoint_destructors_syms;
 622         if (lttng_ust_tracepoint_dlopen_ptr->lttng_ust_tracepoint_module_unregister)
 623                 lttng_ust_tracepoint_dlopen_ptr->lttng_ust_tracepoint_module_unregister(__start_lttng_ust_tracepoints_ptrs);
 624         if (lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle
 625                         && lttng_ust_tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state
 626                         && lttng_ust_tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state()
 627                         && !lttng_ust_tracepoint_ptrs_registered) {
 628                 ret = dlclose(lttng_ust_tracepoint_dlopen_ptr->liblttngust_handle);
 629                 if (ret) {
 630                         fprintf(stderr, "Error (%d) in dlclose\n", ret);
 631                         abort();
 632                 }
 633                 memset(lttng_ust_tracepoint_dlopen_ptr, 0, sizeof(*lttng_ust_tracepoint_dlopen_ptr));
 634         }
 635 }
 636
 637 #else /* LTTNG_UST_TRACEPOINT_DEFINE */
 638
 639 #define LTTNG_UST__DEFINE_TRACEPOINT(_provider, _name, _args)
 640
 641 #endif /* #else LTTNG_UST_TRACEPOINT_DEFINE */
 642
 643 #if LTTNG_UST_COMPAT_API(0)
 644 #define tracepoint                      lttng_ust_tracepoint
 645 #define do_tracepoint                   lttng_ust_do_tracepoint
 646 #define tracepoint_enabled              lttng_ust_tracepoint_enabled
 647 #define TP_ARGS                         LTTNG_UST_TP_ARGS
 648 #endif /* #if LTTNG_UST_COMPAT_API(0) */
 649
 650 #ifdef __cplusplus
 651 }
 652 #endif
 653
 654 #endif /* _LTTNG_UST_TRACEPOINT_H */
 655
 656 /* The following declarations must be outside re-inclusion protection. */
 657
 658 /*
 659  * LTTNG_UST_TRACEPOINT_HIDDEN_DEFINITION: Define this before including
 660  * a tracepoint instrumentation header to hide symbols associated with
 661  * tracepoint module instrumentation. This is useful if all compile
 662  * units using the lttng_ust_tracepoint(),
 663  * lttng_ust_tracepoint_enabled() and lttng_ust_do_tracepoint() macros
 664  * is within the same module as the compile unit including the
 665  * tracepoint header after defining LTTNG_UST_TRACEPOINT_DEFINE.
 666  */
 667
 668 #undef LTTNG_UST__TRACEPOINT_DEFINITION_VISIBILITY
 669 #ifdef LTTNG_UST_TRACEPOINT_HIDDEN_DEFINITION
 670 #define LTTNG_UST__TRACEPOINT_DEFINITION_VISIBILITY             __attribute__((visibility("hidden")))
 671 #else
 672 #define LTTNG_UST__TRACEPOINT_DEFINITION_VISIBILITY             __attribute__((visibility("default")))
 673 #endif
 674
 675 /*
 676  * LTTNG_UST_TRACEPOINT_PROVIDER_HIDDEN_DEFINITION: Define this before
 677  * including a tracepoint instrumentation header to hide symbols
 678  * associated with the tracepoint provider. This is useful if the
 679  * tracepoint definition (including the header after defining
 680  * LTTNG_UST_TRACEPOINT_DEFINE) is in the same module as the provider
 681  * (including the header after defining
 682  * LTTNG_UST_TRACEPOINT_CREATE_PROBES).
 683  */
 684 #undef LTTNG_UST__TRACEPOINT_PROVIDER_DEFINITION_VISIBILITY
 685 #ifdef LTTNG_UST_TRACEPOINT_PROVIDER_HIDDEN_DEFINITION
 686 #define LTTNG_UST__TRACEPOINT_PROVIDER_DEFINITION_VISIBILITY    __attribute__((visibility("hidden")))
 687 #else
 688 #define LTTNG_UST__TRACEPOINT_PROVIDER_DEFINITION_VISIBILITY    __attribute__((visibility("default")))
 689 #endif
 690
 691 #ifndef LTTNG_UST_TRACEPOINT_ENUM
 692
 693 /*
 694  * Tracepoint Enumerations
 695  *
 696  * The enumeration is a mapping between an integer, or range of integers, and
 697  * a string. It can be used to have a more compact trace in cases where the
 698  * possible values for a field are limited:
 699  *
 700  * An example:
 701  *
 702  * LTTNG_UST_TRACEPOINT_ENUM(someproject_component, enumname,
 703  *      LTTNG_UST_TP_ENUM_VALUES(
 704  *              lttng_ust_field_enum_value("even", 0)
 705  *              lttng_ust_field_enum_value("uneven", 1)
 706  *              lttng_ust_field_enum_range("twoto4", 2, 4)
 707  *              lttng_ust_field_enum_value("five", 5)
 708  *      )
 709  * )
 710  *
 711  * Where "someproject_component" is the name of the component this enumeration
 712  * belongs to and "enumname" identifies this enumeration. Inside the
 713  * LTTNG_UST_TP_ENUM_VALUES macro is the actual mapping. Each string value can map
 714  * to either a single value with lttng_ust_field_enum_value or a range of values
 715  * with lttng_ust_field_enum_range.
 716  *
 717  * Enumeration ranges may overlap, but the behavior is implementation-defined,
 718  * each trace reader will handle overlapping as it wishes.
 719  *
 720  * That enumeration can then be used in a field inside the TP_FIELD macro using
 721  * the following line:
 722  *
 723  * lttng_ust_field_enum(someproject_component, enumname, enumtype, enumfield, enumval)
 724  *
 725  * Where "someproject_component" and "enumname" match those in the
 726  * LTTNG_UST_TRACEPOINT_ENUM, "enumtype" is a signed or unsigned integer type
 727  * backing the enumeration, "enumfield" is the name of the field and
 728  * "enumval" is the value.
 729  */
 730
 731 #define LTTNG_UST_TRACEPOINT_ENUM(provider, name, values)
 732
 733 #if LTTNG_UST_COMPAT_API(0)
 734 #define TRACEPOINT_ENUM         LTTNG_UST_TRACEPOINT_ENUM
 735 #endif /* #if LTTNG_UST_COMPAT_API(0) */
 736
 737 #endif /* #ifndef LTTNG_UST_TRACEPOINT_ENUM */
 738
 739 #ifndef LTTNG_UST_TRACEPOINT_EVENT
 740
 741 /*
 742  * How to use the LTTNG_UST_TRACEPOINT_EVENT macro:
 743  *
 744  * An example:
 745  *
 746  * LTTNG_UST_TRACEPOINT_EVENT(someproject_component, event_name,
 747  *
 748  *     * LTTNG_UST_TP_ARGS takes from 0 to 10 "type, field_name" pairs *
 749  *
 750  *     LTTNG_UST_TP_ARGS(int, arg0, void *, arg1, char *, string, size_t, strlen,
 751  *             long *, arg4, size_t, arg4_len),
 752  *
 753  *      * LTTNG_UST_TP_FIELDS describes the event payload layout in the trace *
 754  *
 755  *     LTTNG_UST_TP_FIELDS(
 756  *         * Integer, printed in base 10 *
 757  *         lttng_ust_field_integer(int, field_a, arg0)
 758  *
 759  *         * Integer, printed with 0x base 16 *
 760  *         lttng_ust_field_integer_hex(unsigned long, field_d, arg1)
 761  *
 762  *         * Enumeration *
 763  *         lttng_ust_field_enum(someproject_component, enum_name, int, field_e, arg0)
 764  *
 765  *         * Array Sequence, printed as UTF8-encoded array of bytes *
 766  *         lttng_ust_field_array_text(char, field_b, string, FIXED_LEN)
 767  *         lttng_ust_field_sequence_text(char, field_c, string, size_t, strlen)
 768  *
 769  *         * String, printed as UTF8-encoded string *
 770  *         lttng_ust_field_string(field_e, string)
 771  *
 772  *         * Array sequence of signed integer values *
 773  *         lttng_ust_field_array(long, field_f, arg4, FIXED_LEN4)
 774  *         lttng_ust_field_sequence(long, field_g, arg4, size_t, arg4_len)
 775  *     )
 776  * )
 777  *
 778  * More detailed explanation:
 779  *
 780  * The name of the tracepoint is expressed as a tuple with the provider
 781  * and name arguments.
 782  *
 783  * The provider and name should be a proper C99 identifier.
 784  * The "provider" and "name" MUST follow these rules to ensure no
 785  * namespace clash occurs:
 786  *
 787  * For projects (applications and libraries) for which an entity
 788  * specific to the project controls the source code and thus its
 789  * tracepoints (typically with a scope larger than a single company):
 790  *
 791  * either:
 792  *   project_component, event
 793  * or:
 794  *   project, event
 795  *
 796  * Where "project" is the name of the project,
 797  *       "component" is the name of the project component (which may
 798  *       include several levels of sub-components, e.g.
 799  *       ...component_subcomponent_...) where the tracepoint is located
 800  *       (optional),
 801  *       "event" is the name of the tracepoint event.
 802  *
 803  * For projects issued from a single company wishing to advertise that
 804  * the company controls the source code and thus the tracepoints, the
 805  * "com_" prefix should be used:
 806  *
 807  * either:
 808  *   com_company_project_component, event
 809  * or:
 810  *   com_company_project, event
 811  *
 812  * Where "company" is the name of the company,
 813  *       "project" is the name of the project,
 814  *       "component" is the name of the project component (which may
 815  *       include several levels of sub-components, e.g.
 816  *       ...component_subcomponent_...) where the tracepoint is located
 817  *       (optional),
 818  *       "event" is the name of the tracepoint event.
 819  *
 820  * the provider:event identifier is limited to 127 characters.
 821  */
 822
 823 #define LTTNG_UST_TRACEPOINT_EVENT(provider, name, args, fields)                        \
 824         LTTNG_UST__DECLARE_TRACEPOINT(provider, name, LTTNG_UST__TP_PARAMS(args))               \
 825         LTTNG_UST__DEFINE_TRACEPOINT(provider, name, LTTNG_UST__TP_PARAMS(args))
 826
 827 #define LTTNG_UST_TRACEPOINT_EVENT_CLASS(provider, name, args, fields)
 828
 829 #define LTTNG_UST_TRACEPOINT_EVENT_INSTANCE(template_provider, template_name, provider, name, args)     \
 830         LTTNG_UST__DECLARE_TRACEPOINT(provider, name, LTTNG_UST__TP_PARAMS(args))               \
 831         LTTNG_UST__DEFINE_TRACEPOINT(provider, name, LTTNG_UST__TP_PARAMS(args))
 832
 833 #if LTTNG_UST_COMPAT_API(0)
 834 #define TRACEPOINT_EVENT                LTTNG_UST_TRACEPOINT_EVENT
 835 #define TRACEPOINT_EVENT_CLASS          LTTNG_UST_TRACEPOINT_EVENT_CLASS
 836 #define TRACEPOINT_EVENT_INSTANCE(_provider, _template, _name, args)    \
 837         LTTNG_UST_TRACEPOINT_EVENT_INSTANCE(_provider, _template,       \
 838                 _provider, _name, LTTNG_UST__TP_PARAMS(args))
 839
 840 #endif /* #if LTTNG_UST_COMPAT_API(0) */
 841
 842 #endif /* #ifndef LTTNG_UST_TRACEPOINT_EVENT */
 843
 844 #ifndef LTTNG_UST_TRACEPOINT_LOGLEVEL
 845
 846 /*
 847  * Tracepoint Loglevels
 848  *
 849  * Typical use of these loglevels:
 850  *
 851  * The loglevels go from 0 to 14. Higher numbers imply the most
 852  * verbosity (higher event throughput expected.
 853  *
 854  * Loglevels 0 through 6, and loglevel 14, match syslog(3) loglevels
 855  * semantic. Loglevels 7 through 13 offer more fine-grained selection of
 856  * debug information.
 857  *
 858  * LTTNG_UST_TRACEPOINT_LOGLEVEL_EMERG           0
 859  * system is unusable
 860  *
 861  * LTTNG_UST_TRACEPOINT_LOGLEVEL_ALERT           1
 862  * action must be taken immediately
 863  *
 864  * LTTNG_UST_TRACEPOINT_LOGLEVEL_CRIT            2
 865  * critical conditions
 866  *
 867  * LTTNG_UST_TRACEPOINT_LOGLEVEL_ERR             3
 868  * error conditions
 869  *
 870  * LTTNG_UST_TRACEPOINT_LOGLEVEL_WARNING         4
 871  * warning conditions
 872  *
 873  * LTTNG_UST_TRACEPOINT_LOGLEVEL_NOTICE          5
 874  * normal, but significant, condition
 875  *
 876  * LTTNG_UST_TRACEPOINT_LOGLEVEL_INFO            6
 877  * informational message
 878  *
 879  * LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_SYSTEM    7
 880  * debug information with system-level scope (set of programs)
 881  *
 882  * LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_PROGRAM   8
 883  * debug information with program-level scope (set of processes)
 884  *
 885  * LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_PROCESS   9
 886  * debug information with process-level scope (set of modules)
 887  *
 888  * LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_MODULE    10
 889  * debug information with module (executable/library) scope (set of units)
 890  *
 891  * LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_UNIT      11
 892  * debug information with compilation unit scope (set of functions)
 893  *
 894  * LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_FUNCTION  12
 895  * debug information with function-level scope
 896  *
 897  * LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_LINE      13
 898  * debug information with line-level scope (LTTNG_UST_TRACEPOINT_EVENT default)
 899  *
 900  * LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG           14
 901  * debug-level message
 902  *
 903  * Declare tracepoint loglevels for tracepoints. A LTTNG_UST_TRACEPOINT_EVENT
 904  * should be declared prior to the the LTTNG_UST_TRACEPOINT_LOGLEVEL for a given
 905  * tracepoint name. The first field is the provider name, the second
 906  * field is the name of the tracepoint, the third field is the loglevel
 907  * name.
 908  *
 909  *      LTTNG_UST_TRACEPOINT_LOGLEVEL(< [com_company_]project[_component] >, < event >,
 910  *              < loglevel_name >)
 911  *
 912  * The LTTNG_UST_TRACEPOINT_PROVIDER must be already declared before declaring a
 913  * LTTNG_UST_TRACEPOINT_LOGLEVEL.
 914  */
 915
 916 enum {
 917         LTTNG_UST_TRACEPOINT_LOGLEVEL_EMERG             = 0,
 918         LTTNG_UST_TRACEPOINT_LOGLEVEL_ALERT             = 1,
 919         LTTNG_UST_TRACEPOINT_LOGLEVEL_CRIT              = 2,
 920         LTTNG_UST_TRACEPOINT_LOGLEVEL_ERR               = 3,
 921         LTTNG_UST_TRACEPOINT_LOGLEVEL_WARNING           = 4,
 922         LTTNG_UST_TRACEPOINT_LOGLEVEL_NOTICE            = 5,
 923         LTTNG_UST_TRACEPOINT_LOGLEVEL_INFO              = 6,
 924         LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_SYSTEM      = 7,
 925         LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_PROGRAM     = 8,
 926         LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_PROCESS     = 9,
 927         LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_MODULE      = 10,
 928         LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_UNIT        = 11,
 929         LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_FUNCTION    = 12,
 930         LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_LINE        = 13,
 931         LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG             = 14,
 932 };
 933
 934 #define LTTNG_UST_TRACEPOINT_LOGLEVEL(provider, name, loglevel)
 935
 936 #if LTTNG_UST_COMPAT_API(0)
 937 #define TRACEPOINT_LOGLEVEL     LTTNG_UST_TRACEPOINT_LOGLEVEL
 938
 939 #define TRACE_EMERG             LTTNG_UST_TRACEPOINT_LOGLEVEL_EMERG
 940 #define TRACE_ALERT             LTTNG_UST_TRACEPOINT_LOGLEVEL_ALERT
 941 #define TRACE_CRIT              LTTNG_UST_TRACEPOINT_LOGLEVEL_CRIT
 942 #define TRACE_ERR               LTTNG_UST_TRACEPOINT_LOGLEVEL_ERR
 943 #define TRACE_WARNING           LTTNG_UST_TRACEPOINT_LOGLEVEL_WARNING
 944 #define TRACE_NOTICE            LTTNG_UST_TRACEPOINT_LOGLEVEL_NOTICE
 945 #define TRACE_INFO              LTTNG_UST_TRACEPOINT_LOGLEVEL_INFO
 946 #define TRACE_DEBUG_SYSTEM      LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_SYSTEM
 947 #define TRACE_DEBUG_PROGRAM     LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_PROGRAM
 948 #define TRACE_DEBUG_PROCESS     LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_PROCESS
 949 #define TRACE_DEBUG_MODULE      LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_MODULE
 950 #define TRACE_DEBUG_UNIT        LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_UNIT
 951 #define TRACE_DEBUG_FUNCTION    LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_FUNCTION
 952 #define TRACE_DEBUG_LINE        LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG_LINE
 953 #define TRACE_DEBUG             LTTNG_UST_TRACEPOINT_LOGLEVEL_DEBUG
 954 #endif
 955
 956 #endif /* #ifndef LTTNG_UST_TRACEPOINT_LOGLEVEL */
 957
 958 #ifndef LTTNG_UST_TRACEPOINT_MODEL_EMF_URI
 959
 960 #define LTTNG_UST_TRACEPOINT_MODEL_EMF_URI(provider, name, uri)
 961
 962 #if LTTNG_UST_COMPAT_API(0)
 963 #define TRACEPOINT_MODEL_EMF_URI LTTNG_UST_TRACEPOINT_MODEL_EMF_URI
 964 #endif
 965
 966 #endif /* #ifndef LTTNG_UST_TRACEPOINT_MODEL_EMF_URI */