| 1 | #ifndef _LTTNG_TRACEPOINT_H |
| 2 | #define _LTTNG_TRACEPOINT_H |
| 3 | |
| 4 | /* |
| 5 | * Copyright 2011-2012 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| 6 | * |
| 7 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 8 | * of this software and associated documentation files (the "Software"), to deal |
| 9 | * in the Software without restriction, including without limitation the rights |
| 10 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 11 | * copies of the Software, and to permit persons to whom the Software is |
| 12 | * furnished to do so, subject to the following conditions: |
| 13 | * |
| 14 | * The above copyright notice and this permission notice shall be included in |
| 15 | * all copies or substantial portions of the Software. |
| 16 | * |
| 17 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 18 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 19 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 20 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 21 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 22 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| 23 | * SOFTWARE. |
| 24 | */ |
| 25 | |
| 26 | #include <stdio.h> |
| 27 | #include <stdlib.h> |
| 28 | #include <lttng/tracepoint-types.h> |
| 29 | #include <lttng/tracepoint-rcu.h> |
| 30 | #include <urcu/compiler.h> |
| 31 | #include <urcu/system.h> |
| 32 | #include <dlfcn.h> /* for dlopen */ |
| 33 | #include <string.h> /* for memset */ |
| 34 | #include <lttng/ust-config.h> /* for sdt */ |
| 35 | #include <lttng/ust-compiler.h> |
| 36 | |
| 37 | #ifdef LTTNG_UST_HAVE_SDT_INTEGRATION |
| 38 | /* |
| 39 | * Instead of using SDT_USE_VARIADIC from 'sys/sdt.h', use our own namespaced |
| 40 | * macros since the instrumented application might already have included |
| 41 | * 'sys/sdt.h' without variadic support. |
| 42 | */ |
| 43 | #include <sys/sdt.h> |
| 44 | |
| 45 | #define _LTTNG_SDT_NARG(...) \ |
| 46 | __LTTNG_SDT_NARG(__VA_ARGS__, 12,11,10,9,8,7,6,5,4,3,2,1,0) |
| 47 | |
| 48 | #define __LTTNG_SDT_NARG(_0,_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,_11,_12, N, ...) N |
| 49 | |
| 50 | #define _LTTNG_SDT_PROBE_N(provider, name, N, ...) \ |
| 51 | _SDT_PROBE(provider, name, N, (__VA_ARGS__)) |
| 52 | |
| 53 | #define LTTNG_STAP_PROBEV(provider, name, ...) \ |
| 54 | _LTTNG_SDT_PROBE_N(provider, name, _LTTNG_SDT_NARG(0, ##__VA_ARGS__), ##__VA_ARGS__) |
| 55 | |
| 56 | #else |
| 57 | #define LTTNG_STAP_PROBEV(...) |
| 58 | #endif |
| 59 | |
| 60 | #ifdef __cplusplus |
| 61 | extern "C" { |
| 62 | #endif |
| 63 | |
| 64 | #define tracepoint_enabled(provider, name) \ |
| 65 | caa_unlikely(CMM_LOAD_SHARED(__tracepoint_##provider##___##name.state)) |
| 66 | |
| 67 | #define do_tracepoint(provider, name, ...) \ |
| 68 | __tracepoint_cb_##provider##___##name(__VA_ARGS__) |
| 69 | |
| 70 | #define tracepoint(provider, name, ...) \ |
| 71 | do { \ |
| 72 | LTTNG_STAP_PROBEV(provider, name, ## __VA_ARGS__); \ |
| 73 | if (tracepoint_enabled(provider, name)) \ |
| 74 | do_tracepoint(provider, name, __VA_ARGS__); \ |
| 75 | } while (0) |
| 76 | |
| 77 | #define TP_ARGS(...) __VA_ARGS__ |
| 78 | |
| 79 | /* |
| 80 | * TP_ARGS takes tuples of type, argument separated by a comma. |
| 81 | * It can take up to 10 tuples (which means that less than 10 tuples is |
| 82 | * fine too). |
| 83 | * Each tuple is also separated by a comma. |
| 84 | */ |
| 85 | #define __TP_COMBINE_TOKENS(_tokena, _tokenb) \ |
| 86 | _tokena##_tokenb |
| 87 | #define _TP_COMBINE_TOKENS(_tokena, _tokenb) \ |
| 88 | __TP_COMBINE_TOKENS(_tokena, _tokenb) |
| 89 | #define __TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc) \ |
| 90 | _tokena##_tokenb##_tokenc |
| 91 | #define _TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc) \ |
| 92 | __TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc) |
| 93 | #define __TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend) \ |
| 94 | _tokena##_tokenb##_tokenc##_tokend |
| 95 | #define _TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend) \ |
| 96 | __TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend) |
| 97 | |
| 98 | /* |
| 99 | * _TP_EXVAR* extract the var names. |
| 100 | * _TP_EXVAR1 and _TP_EXDATA_VAR1 are needed for -std=c99. |
| 101 | */ |
| 102 | #define _TP_EXVAR0() |
| 103 | #define _TP_EXVAR1(a) |
| 104 | #define _TP_EXVAR2(a,b) b |
| 105 | #define _TP_EXVAR4(a,b,c,d) b,d |
| 106 | #define _TP_EXVAR6(a,b,c,d,e,f) b,d,f |
| 107 | #define _TP_EXVAR8(a,b,c,d,e,f,g,h) b,d,f,h |
| 108 | #define _TP_EXVAR10(a,b,c,d,e,f,g,h,i,j) b,d,f,h,j |
| 109 | #define _TP_EXVAR12(a,b,c,d,e,f,g,h,i,j,k,l) b,d,f,h,j,l |
| 110 | #define _TP_EXVAR14(a,b,c,d,e,f,g,h,i,j,k,l,m,n) b,d,f,h,j,l,n |
| 111 | #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 |
| 112 | #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 |
| 113 | #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 |
| 114 | |
| 115 | #define _TP_EXDATA_VAR0() __tp_data |
| 116 | #define _TP_EXDATA_VAR1(a) __tp_data |
| 117 | #define _TP_EXDATA_VAR2(a,b) __tp_data,b |
| 118 | #define _TP_EXDATA_VAR4(a,b,c,d) __tp_data,b,d |
| 119 | #define _TP_EXDATA_VAR6(a,b,c,d,e,f) __tp_data,b,d,f |
| 120 | #define _TP_EXDATA_VAR8(a,b,c,d,e,f,g,h) __tp_data,b,d,f,h |
| 121 | #define _TP_EXDATA_VAR10(a,b,c,d,e,f,g,h,i,j) __tp_data,b,d,f,h,j |
| 122 | #define _TP_EXDATA_VAR12(a,b,c,d,e,f,g,h,i,j,k,l) __tp_data,b,d,f,h,j,l |
| 123 | #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 |
| 124 | #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 |
| 125 | #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 |
| 126 | #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 |
| 127 | |
| 128 | /* |
| 129 | * _TP_EXPROTO* extract tuples of type, var. |
| 130 | * _TP_EXPROTO1 and _TP_EXDATA_PROTO1 are needed for -std=c99. |
| 131 | */ |
| 132 | #define _TP_EXPROTO0() void |
| 133 | #define _TP_EXPROTO1(a) void |
| 134 | #define _TP_EXPROTO2(a,b) a b |
| 135 | #define _TP_EXPROTO4(a,b,c,d) a b,c d |
| 136 | #define _TP_EXPROTO6(a,b,c,d,e,f) a b,c d,e f |
| 137 | #define _TP_EXPROTO8(a,b,c,d,e,f,g,h) a b,c d,e f,g h |
| 138 | #define _TP_EXPROTO10(a,b,c,d,e,f,g,h,i,j) a b,c d,e f,g h,i j |
| 139 | #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 |
| 140 | #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 |
| 141 | #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 |
| 142 | #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 |
| 143 | #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 |
| 144 | |
| 145 | #define _TP_EXDATA_PROTO0() void *__tp_data |
| 146 | #define _TP_EXDATA_PROTO1(a) void *__tp_data |
| 147 | #define _TP_EXDATA_PROTO2(a,b) void *__tp_data,a b |
| 148 | #define _TP_EXDATA_PROTO4(a,b,c,d) void *__tp_data,a b,c d |
| 149 | #define _TP_EXDATA_PROTO6(a,b,c,d,e,f) void *__tp_data,a b,c d,e f |
| 150 | #define _TP_EXDATA_PROTO8(a,b,c,d,e,f,g,h) void *__tp_data,a b,c d,e f,g h |
| 151 | #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 |
| 152 | #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 |
| 153 | #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 |
| 154 | #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 |
| 155 | #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 |
| 156 | #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 |
| 157 | |
| 158 | /* Preprocessor trick to count arguments. Inspired from sdt.h. */ |
| 159 | #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) |
| 160 | #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 |
| 161 | #define _TP_PROTO_N(N, ...) _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXPROTO, N)(__VA_ARGS__)) |
| 162 | #define _TP_VAR_N(N, ...) _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXVAR, N)(__VA_ARGS__)) |
| 163 | #define _TP_DATA_PROTO_N(N, ...) _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXDATA_PROTO, N)(__VA_ARGS__)) |
| 164 | #define _TP_DATA_VAR_N(N, ...) _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXDATA_VAR, N)(__VA_ARGS__)) |
| 165 | #define _TP_ARGS_PROTO(...) _TP_PROTO_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__) |
| 166 | #define _TP_ARGS_VAR(...) _TP_VAR_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__) |
| 167 | #define _TP_ARGS_DATA_PROTO(...) _TP_DATA_PROTO_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__) |
| 168 | #define _TP_ARGS_DATA_VAR(...) _TP_DATA_VAR_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__) |
| 169 | #define _TP_PARAMS(...) __VA_ARGS__ |
| 170 | |
| 171 | /* |
| 172 | * The tracepoint cb is marked always inline so we can distinguish |
| 173 | * between caller's ip addresses within the probe using the return |
| 174 | * address. |
| 175 | */ |
| 176 | #define _DECLARE_TRACEPOINT(_provider, _name, ...) \ |
| 177 | extern struct lttng_ust_tracepoint __tracepoint_##_provider##___##_name; \ |
| 178 | static inline __attribute__((always_inline, unused)) lttng_ust_notrace \ |
| 179 | void __tracepoint_cb_##_provider##___##_name(_TP_ARGS_PROTO(__VA_ARGS__)); \ |
| 180 | static \ |
| 181 | void __tracepoint_cb_##_provider##___##_name(_TP_ARGS_PROTO(__VA_ARGS__)) \ |
| 182 | { \ |
| 183 | struct lttng_ust_tracepoint_probe *__tp_probe; \ |
| 184 | \ |
| 185 | if (caa_unlikely(!TP_RCU_LINK_TEST())) \ |
| 186 | return; \ |
| 187 | tp_rcu_read_lock_bp(); \ |
| 188 | __tp_probe = tp_rcu_dereference_bp(__tracepoint_##_provider##___##_name.probes); \ |
| 189 | if (caa_unlikely(!__tp_probe)) \ |
| 190 | goto end; \ |
| 191 | do { \ |
| 192 | void (*__tp_cb)(void) = __tp_probe->func; \ |
| 193 | void *__tp_data = __tp_probe->data; \ |
| 194 | \ |
| 195 | URCU_FORCE_CAST(void (*)(_TP_ARGS_DATA_PROTO(__VA_ARGS__)), __tp_cb) \ |
| 196 | (_TP_ARGS_DATA_VAR(__VA_ARGS__)); \ |
| 197 | } while ((++__tp_probe)->func); \ |
| 198 | end: \ |
| 199 | tp_rcu_read_unlock_bp(); \ |
| 200 | } \ |
| 201 | static inline lttng_ust_notrace \ |
| 202 | void __tracepoint_register_##_provider##___##_name(char *name, \ |
| 203 | void (*func)(void), void *data); \ |
| 204 | static inline \ |
| 205 | void __tracepoint_register_##_provider##___##_name(char *name, \ |
| 206 | void (*func)(void), void *data) \ |
| 207 | { \ |
| 208 | __tracepoint_probe_register(name, func, data, \ |
| 209 | __tracepoint_##_provider##___##_name.signature); \ |
| 210 | } \ |
| 211 | static inline lttng_ust_notrace \ |
| 212 | void __tracepoint_unregister_##_provider##___##_name(char *name, \ |
| 213 | void (*func)(void), void *data); \ |
| 214 | static inline \ |
| 215 | void __tracepoint_unregister_##_provider##___##_name(char *name, \ |
| 216 | void (*func)(void), void *data) \ |
| 217 | { \ |
| 218 | __tracepoint_probe_unregister(name, func, data); \ |
| 219 | } |
| 220 | |
| 221 | extern int __tracepoint_probe_register(const char *name, void (*func)(void), |
| 222 | void *data, const char *signature); |
| 223 | extern int __tracepoint_probe_unregister(const char *name, void (*func)(void), |
| 224 | void *data); |
| 225 | |
| 226 | /* |
| 227 | * tracepoint dynamic linkage handling (callbacks). Hidden visibility: |
| 228 | * shared across objects in a module/main executable. |
| 229 | */ |
| 230 | struct lttng_ust_tracepoint_dlopen { |
| 231 | void *liblttngust_handle; |
| 232 | |
| 233 | int (*tracepoint_register_lib)(struct lttng_ust_tracepoint * const *tracepoints_start, |
| 234 | int tracepoints_count); |
| 235 | int (*tracepoint_unregister_lib)(struct lttng_ust_tracepoint * const *tracepoints_start); |
| 236 | void (*rcu_read_lock_sym_bp)(void); |
| 237 | void (*rcu_read_unlock_sym_bp)(void); |
| 238 | void *(*rcu_dereference_sym_bp)(void *p); |
| 239 | }; |
| 240 | |
| 241 | extern struct lttng_ust_tracepoint_dlopen tracepoint_dlopen; |
| 242 | extern struct lttng_ust_tracepoint_dlopen *tracepoint_dlopen_ptr; |
| 243 | |
| 244 | /* |
| 245 | * These weak symbols, the constructor, and destructor take care of |
| 246 | * registering only _one_ instance of the tracepoints per shared-ojbect |
| 247 | * (or for the whole main program). |
| 248 | */ |
| 249 | int __tracepoint_registered |
| 250 | __attribute__((weak, visibility("hidden"))); |
| 251 | int __tracepoint_ptrs_registered |
| 252 | __attribute__((weak, visibility("hidden"))); |
| 253 | struct lttng_ust_tracepoint_dlopen tracepoint_dlopen |
| 254 | __attribute__((weak, visibility("hidden"))); |
| 255 | /* |
| 256 | * Deal with gcc O1 optimisation issues with weak hidden symbols. gcc |
| 257 | * 4.8 and prior does not have the same behavior for symbol scoping on |
| 258 | * 32-bit powerpc depending on the object size: symbols for objects of 8 |
| 259 | * bytes or less have the same address throughout a module, whereas they |
| 260 | * have different addresses between compile units for objects larger |
| 261 | * than 8 bytes. Add this pointer indirection to ensure that the symbol |
| 262 | * scoping match that of the other weak hidden symbols found in this |
| 263 | * header. |
| 264 | */ |
| 265 | struct lttng_ust_tracepoint_dlopen *tracepoint_dlopen_ptr |
| 266 | __attribute__((weak, visibility("hidden"))); |
| 267 | |
| 268 | /* |
| 269 | * Tracepoint dynamic linkage handling (callbacks). Hidden visibility: shared |
| 270 | * across objects in a module/main executable. The callbacks are used to |
| 271 | * control and check if the destructors should be executed. |
| 272 | */ |
| 273 | struct lttng_ust_tracepoint_destructors_syms { |
| 274 | int *old_tracepoint_disable_destructors; |
| 275 | void (*tracepoint_disable_destructors)(void); |
| 276 | int (*tracepoint_get_destructors_state)(void); |
| 277 | }; |
| 278 | |
| 279 | extern struct lttng_ust_tracepoint_destructors_syms tracepoint_destructors_syms; |
| 280 | extern struct lttng_ust_tracepoint_destructors_syms *tracepoint_destructors_syms_ptr; |
| 281 | |
| 282 | struct lttng_ust_tracepoint_destructors_syms tracepoint_destructors_syms |
| 283 | __attribute__((weak, visibility("hidden"))); |
| 284 | struct lttng_ust_tracepoint_destructors_syms *tracepoint_destructors_syms_ptr |
| 285 | __attribute__((weak, visibility("hidden"))); |
| 286 | |
| 287 | static inline void tracepoint_disable_destructors(void) |
| 288 | { |
| 289 | if (!tracepoint_dlopen_ptr) |
| 290 | tracepoint_dlopen_ptr = &tracepoint_dlopen; |
| 291 | if (!tracepoint_destructors_syms_ptr) |
| 292 | tracepoint_destructors_syms_ptr = &tracepoint_destructors_syms; |
| 293 | if (tracepoint_dlopen_ptr->liblttngust_handle |
| 294 | && tracepoint_destructors_syms_ptr->tracepoint_disable_destructors) |
| 295 | tracepoint_destructors_syms_ptr->tracepoint_disable_destructors(); |
| 296 | *tracepoint_destructors_syms_ptr->old_tracepoint_disable_destructors = 1; |
| 297 | } |
| 298 | |
| 299 | #ifndef _LGPL_SOURCE |
| 300 | static inline void lttng_ust_notrace |
| 301 | __tracepoint__init_urcu_sym(void); |
| 302 | static inline void |
| 303 | __tracepoint__init_urcu_sym(void) |
| 304 | { |
| 305 | if (!tracepoint_dlopen_ptr) |
| 306 | tracepoint_dlopen_ptr = &tracepoint_dlopen; |
| 307 | /* |
| 308 | * Symbols below are needed by tracepoint call sites and probe |
| 309 | * providers. |
| 310 | */ |
| 311 | if (!tracepoint_dlopen_ptr->rcu_read_lock_sym_bp) |
| 312 | tracepoint_dlopen_ptr->rcu_read_lock_sym_bp = |
| 313 | URCU_FORCE_CAST(void (*)(void), |
| 314 | dlsym(tracepoint_dlopen_ptr->liblttngust_handle, |
| 315 | "tp_rcu_read_lock_bp")); |
| 316 | if (!tracepoint_dlopen_ptr->rcu_read_unlock_sym_bp) |
| 317 | tracepoint_dlopen_ptr->rcu_read_unlock_sym_bp = |
| 318 | URCU_FORCE_CAST(void (*)(void), |
| 319 | dlsym(tracepoint_dlopen_ptr->liblttngust_handle, |
| 320 | "tp_rcu_read_unlock_bp")); |
| 321 | if (!tracepoint_dlopen_ptr->rcu_dereference_sym_bp) |
| 322 | tracepoint_dlopen_ptr->rcu_dereference_sym_bp = |
| 323 | URCU_FORCE_CAST(void *(*)(void *p), |
| 324 | dlsym(tracepoint_dlopen_ptr->liblttngust_handle, |
| 325 | "tp_rcu_dereference_sym_bp")); |
| 326 | } |
| 327 | #else |
| 328 | static inline void lttng_ust_notrace |
| 329 | __tracepoint__init_urcu_sym(void); |
| 330 | static inline void |
| 331 | __tracepoint__init_urcu_sym(void) |
| 332 | { |
| 333 | } |
| 334 | #endif |
| 335 | |
| 336 | static void lttng_ust_notrace __attribute__((constructor)) |
| 337 | __tracepoints__init(void); |
| 338 | static void |
| 339 | __tracepoints__init(void) |
| 340 | { |
| 341 | if (__tracepoint_registered++) { |
| 342 | if (!tracepoint_dlopen_ptr->liblttngust_handle) |
| 343 | return; |
| 344 | __tracepoint__init_urcu_sym(); |
| 345 | return; |
| 346 | } |
| 347 | |
| 348 | if (!tracepoint_dlopen_ptr) |
| 349 | tracepoint_dlopen_ptr = &tracepoint_dlopen; |
| 350 | if (!tracepoint_dlopen_ptr->liblttngust_handle) |
| 351 | tracepoint_dlopen_ptr->liblttngust_handle = |
| 352 | dlopen("liblttng-ust-tracepoint.so.0", RTLD_NOW | RTLD_GLOBAL); |
| 353 | if (!tracepoint_dlopen_ptr->liblttngust_handle) |
| 354 | return; |
| 355 | __tracepoint__init_urcu_sym(); |
| 356 | } |
| 357 | |
| 358 | static void lttng_ust_notrace __attribute__((destructor)) |
| 359 | __tracepoints__destroy(void); |
| 360 | static void |
| 361 | __tracepoints__destroy(void) |
| 362 | { |
| 363 | int ret; |
| 364 | |
| 365 | if (--__tracepoint_registered) |
| 366 | return; |
| 367 | if (!tracepoint_dlopen_ptr) |
| 368 | tracepoint_dlopen_ptr = &tracepoint_dlopen; |
| 369 | if (!tracepoint_destructors_syms_ptr) |
| 370 | tracepoint_destructors_syms_ptr = &tracepoint_destructors_syms; |
| 371 | if (!tracepoint_dlopen_ptr->liblttngust_handle) |
| 372 | return; |
| 373 | if (__tracepoint_ptrs_registered) |
| 374 | return; |
| 375 | /* |
| 376 | * Lookup if destructors must be executed using the new method. |
| 377 | */ |
| 378 | if (tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state |
| 379 | && !tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state()) { |
| 380 | /* |
| 381 | * The tracepoint_get_destructors_state symbol was found with |
| 382 | * dlsym but its returned value is 0 meaning that destructors |
| 383 | * must not be executed. |
| 384 | */ |
| 385 | return; |
| 386 | } |
| 387 | /* |
| 388 | * Lookup if destructors must be executed using the old method. |
| 389 | */ |
| 390 | if (tracepoint_destructors_syms_ptr->old_tracepoint_disable_destructors |
| 391 | && *tracepoint_destructors_syms_ptr->old_tracepoint_disable_destructors) { |
| 392 | /* |
| 393 | * The old_tracepoint_disable_destructors symbol was found with |
| 394 | * dlsym but its value is 1 meaning that destructors must not |
| 395 | * be executed. |
| 396 | */ |
| 397 | return; |
| 398 | } |
| 399 | |
| 400 | ret = dlclose(tracepoint_dlopen_ptr->liblttngust_handle); |
| 401 | if (ret) { |
| 402 | fprintf(stderr, "Error (%d) in dlclose\n", ret); |
| 403 | abort(); |
| 404 | } |
| 405 | memset(tracepoint_dlopen_ptr, 0, sizeof(*tracepoint_dlopen_ptr)); |
| 406 | } |
| 407 | |
| 408 | #ifdef TRACEPOINT_DEFINE |
| 409 | |
| 410 | /* |
| 411 | * These weak symbols, the constructor, and destructor take care of |
| 412 | * registering only _one_ instance of the tracepoints per shared-ojbect |
| 413 | * (or for the whole main program). |
| 414 | */ |
| 415 | extern struct lttng_ust_tracepoint * const __start___tracepoints_ptrs[] |
| 416 | __attribute__((weak, visibility("hidden"))); |
| 417 | extern struct lttng_ust_tracepoint * const __stop___tracepoints_ptrs[] |
| 418 | __attribute__((weak, visibility("hidden"))); |
| 419 | |
| 420 | /* |
| 421 | * When TRACEPOINT_PROBE_DYNAMIC_LINKAGE is defined, we do not emit a |
| 422 | * unresolved symbol that requires the provider to be linked in. When |
| 423 | * TRACEPOINT_PROBE_DYNAMIC_LINKAGE is not defined, we emit an |
| 424 | * unresolved symbol that depends on having the provider linked in, |
| 425 | * otherwise the linker complains. This deals with use of static |
| 426 | * libraries, ensuring that the linker does not remove the provider |
| 427 | * object from the executable. |
| 428 | */ |
| 429 | #ifdef TRACEPOINT_PROBE_DYNAMIC_LINKAGE |
| 430 | #define _TRACEPOINT_UNDEFINED_REF(provider) NULL |
| 431 | #else /* TRACEPOINT_PROBE_DYNAMIC_LINKAGE */ |
| 432 | #define _TRACEPOINT_UNDEFINED_REF(provider) &__tracepoint_provider_##provider |
| 433 | #endif /* TRACEPOINT_PROBE_DYNAMIC_LINKAGE */ |
| 434 | |
| 435 | /* |
| 436 | * Note: to allow PIC code, we need to allow the linker to update the pointers |
| 437 | * in the __tracepoints_ptrs section. |
| 438 | * Therefore, this section is _not_ const (read-only). |
| 439 | */ |
| 440 | #define _TP_EXTRACT_STRING(...) #__VA_ARGS__ |
| 441 | |
| 442 | #define _DEFINE_TRACEPOINT(_provider, _name, _args) \ |
| 443 | extern int __tracepoint_provider_##_provider; \ |
| 444 | static const char __tp_strtab_##_provider##___##_name[] \ |
| 445 | __attribute__((section("__tracepoints_strings"))) = \ |
| 446 | #_provider ":" #_name; \ |
| 447 | struct lttng_ust_tracepoint __tracepoint_##_provider##___##_name \ |
| 448 | __attribute__((section("__tracepoints"))) = \ |
| 449 | { \ |
| 450 | __tp_strtab_##_provider##___##_name, \ |
| 451 | 0, \ |
| 452 | NULL, \ |
| 453 | _TRACEPOINT_UNDEFINED_REF(_provider), \ |
| 454 | _TP_EXTRACT_STRING(_args), \ |
| 455 | { }, \ |
| 456 | }; \ |
| 457 | static struct lttng_ust_tracepoint * \ |
| 458 | __tracepoint_ptr_##_provider##___##_name \ |
| 459 | __attribute__((section("__tracepoints_ptrs"), used)) \ |
| 460 | __lttng_ust_variable_attribute_no_sanitize_address = \ |
| 461 | &__tracepoint_##_provider##___##_name; |
| 462 | |
| 463 | static void lttng_ust_notrace __attribute__((constructor)) |
| 464 | __tracepoints__ptrs_init(void); |
| 465 | static void |
| 466 | __tracepoints__ptrs_init(void) |
| 467 | { |
| 468 | if (__tracepoint_ptrs_registered++) |
| 469 | return; |
| 470 | if (!tracepoint_dlopen_ptr) |
| 471 | tracepoint_dlopen_ptr = &tracepoint_dlopen; |
| 472 | if (!tracepoint_dlopen_ptr->liblttngust_handle) |
| 473 | tracepoint_dlopen_ptr->liblttngust_handle = |
| 474 | dlopen("liblttng-ust-tracepoint.so.0", RTLD_NOW | RTLD_GLOBAL); |
| 475 | if (!tracepoint_dlopen_ptr->liblttngust_handle) |
| 476 | return; |
| 477 | if (!tracepoint_destructors_syms_ptr) |
| 478 | tracepoint_destructors_syms_ptr = &tracepoint_destructors_syms; |
| 479 | tracepoint_dlopen_ptr->tracepoint_register_lib = |
| 480 | URCU_FORCE_CAST(int (*)(struct lttng_ust_tracepoint * const *, int), |
| 481 | dlsym(tracepoint_dlopen_ptr->liblttngust_handle, |
| 482 | "tracepoint_register_lib")); |
| 483 | tracepoint_dlopen_ptr->tracepoint_unregister_lib = |
| 484 | URCU_FORCE_CAST(int (*)(struct lttng_ust_tracepoint * const *), |
| 485 | dlsym(tracepoint_dlopen_ptr->liblttngust_handle, |
| 486 | "tracepoint_unregister_lib")); |
| 487 | tracepoint_destructors_syms_ptr->old_tracepoint_disable_destructors = |
| 488 | URCU_FORCE_CAST(int *, |
| 489 | dlsym(tracepoint_dlopen_ptr->liblttngust_handle, |
| 490 | "__tracepoints__disable_destructors")); |
| 491 | tracepoint_destructors_syms_ptr->tracepoint_disable_destructors = |
| 492 | URCU_FORCE_CAST(void (*)(void), |
| 493 | dlsym(tracepoint_dlopen_ptr->liblttngust_handle, |
| 494 | "tp_disable_destructors")); |
| 495 | tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state = |
| 496 | URCU_FORCE_CAST(int (*)(void), |
| 497 | dlsym(tracepoint_dlopen_ptr->liblttngust_handle, |
| 498 | "tp_get_destructors_state")); |
| 499 | __tracepoint__init_urcu_sym(); |
| 500 | if (tracepoint_dlopen_ptr->tracepoint_register_lib) { |
| 501 | tracepoint_dlopen_ptr->tracepoint_register_lib(__start___tracepoints_ptrs, |
| 502 | __stop___tracepoints_ptrs - |
| 503 | __start___tracepoints_ptrs); |
| 504 | } |
| 505 | } |
| 506 | |
| 507 | static void lttng_ust_notrace __attribute__((destructor)) |
| 508 | __tracepoints__ptrs_destroy(void); |
| 509 | static void |
| 510 | __tracepoints__ptrs_destroy(void) |
| 511 | { |
| 512 | int ret; |
| 513 | |
| 514 | if (--__tracepoint_ptrs_registered) |
| 515 | return; |
| 516 | if (!tracepoint_dlopen_ptr) |
| 517 | tracepoint_dlopen_ptr = &tracepoint_dlopen; |
| 518 | if (!tracepoint_destructors_syms_ptr) |
| 519 | tracepoint_destructors_syms_ptr = &tracepoint_destructors_syms; |
| 520 | if (tracepoint_dlopen_ptr->tracepoint_unregister_lib) |
| 521 | tracepoint_dlopen_ptr->tracepoint_unregister_lib(__start___tracepoints_ptrs); |
| 522 | if (tracepoint_dlopen_ptr->liblttngust_handle |
| 523 | && tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state |
| 524 | && tracepoint_destructors_syms_ptr->tracepoint_get_destructors_state() |
| 525 | && !__tracepoint_ptrs_registered) { |
| 526 | ret = dlclose(tracepoint_dlopen_ptr->liblttngust_handle); |
| 527 | if (ret) { |
| 528 | fprintf(stderr, "Error (%d) in dlclose\n", ret); |
| 529 | abort(); |
| 530 | } |
| 531 | memset(tracepoint_dlopen_ptr, 0, sizeof(*tracepoint_dlopen_ptr)); |
| 532 | } |
| 533 | } |
| 534 | |
| 535 | #else /* TRACEPOINT_DEFINE */ |
| 536 | |
| 537 | #define _DEFINE_TRACEPOINT(_provider, _name, _args) |
| 538 | |
| 539 | #endif /* #else TRACEPOINT_DEFINE */ |
| 540 | |
| 541 | #ifdef __cplusplus |
| 542 | } |
| 543 | #endif |
| 544 | |
| 545 | #endif /* _LTTNG_TRACEPOINT_H */ |
| 546 | |
| 547 | /* The following declarations must be outside re-inclusion protection. */ |
| 548 | |
| 549 | #ifndef TRACEPOINT_ENUM |
| 550 | |
| 551 | /* |
| 552 | * Tracepoint Enumerations |
| 553 | * |
| 554 | * The enumeration is a mapping between an integer, or range of integers, and |
| 555 | * a string. It can be used to have a more compact trace in cases where the |
| 556 | * possible values for a field are limited: |
| 557 | * |
| 558 | * An example: |
| 559 | * |
| 560 | * TRACEPOINT_ENUM(someproject_component, enumname, |
| 561 | * TP_ENUM_VALUES( |
| 562 | * ctf_enum_value("even", 0) |
| 563 | * ctf_enum_value("uneven", 1) |
| 564 | * ctf_enum_range("twoto4", 2, 4) |
| 565 | * ctf_enum_value("five", 5) |
| 566 | * ) |
| 567 | * ) |
| 568 | * |
| 569 | * Where "someproject_component" is the name of the component this enumeration |
| 570 | * belongs to and "enumname" identifies this enumeration. Inside the |
| 571 | * TP_ENUM_VALUES macro is the actual mapping. Each string value can map |
| 572 | * to either a single value with ctf_enum_value or a range of values |
| 573 | * with ctf_enum_range. |
| 574 | * |
| 575 | * Enumeration ranges may overlap, but the behavior is implementation-defined, |
| 576 | * each trace reader will handle overlapping as it wishes. |
| 577 | * |
| 578 | * That enumeration can then be used in a field inside the TP_FIELD macro using |
| 579 | * the following line: |
| 580 | * |
| 581 | * ctf_enum(someproject_component, enumname, enumtype, enumfield, enumval) |
| 582 | * |
| 583 | * Where "someproject_component" and "enumname" match those in the |
| 584 | * TRACEPOINT_ENUM, "enumtype" is a signed or unsigned integer type |
| 585 | * backing the enumeration, "enumfield" is the name of the field and |
| 586 | * "enumval" is the value. |
| 587 | */ |
| 588 | |
| 589 | #define TRACEPOINT_ENUM(provider, name, values) |
| 590 | |
| 591 | #endif /* #ifndef TRACEPOINT_ENUM */ |
| 592 | |
| 593 | #ifndef TRACEPOINT_EVENT |
| 594 | |
| 595 | /* |
| 596 | * How to use the TRACEPOINT_EVENT macro: |
| 597 | * |
| 598 | * An example: |
| 599 | * |
| 600 | * TRACEPOINT_EVENT(someproject_component, event_name, |
| 601 | * |
| 602 | * * TP_ARGS takes from 0 to 10 "type, field_name" pairs * |
| 603 | * |
| 604 | * TP_ARGS(int, arg0, void *, arg1, char *, string, size_t, strlen, |
| 605 | * long *, arg4, size_t, arg4_len), |
| 606 | * |
| 607 | * * TP_FIELDS describes the event payload layout in the trace * |
| 608 | * |
| 609 | * TP_FIELDS( |
| 610 | * * Integer, printed in base 10 * |
| 611 | * ctf_integer(int, field_a, arg0) |
| 612 | * |
| 613 | * * Integer, printed with 0x base 16 * |
| 614 | * ctf_integer_hex(unsigned long, field_d, arg1) |
| 615 | * |
| 616 | * * Enumeration * |
| 617 | * ctf_enum(someproject_component, enum_name, int, field_e, arg0) |
| 618 | * |
| 619 | * * Array Sequence, printed as UTF8-encoded array of bytes * |
| 620 | * ctf_array_text(char, field_b, string, FIXED_LEN) |
| 621 | * ctf_sequence_text(char, field_c, string, size_t, strlen) |
| 622 | * |
| 623 | * * String, printed as UTF8-encoded string * |
| 624 | * ctf_string(field_e, string) |
| 625 | * |
| 626 | * * Array sequence of signed integer values * |
| 627 | * ctf_array(long, field_f, arg4, FIXED_LEN4) |
| 628 | * ctf_sequence(long, field_g, arg4, size_t, arg4_len) |
| 629 | * ) |
| 630 | * ) |
| 631 | * |
| 632 | * More detailed explanation: |
| 633 | * |
| 634 | * The name of the tracepoint is expressed as a tuple with the provider |
| 635 | * and name arguments. |
| 636 | * |
| 637 | * The provider and name should be a proper C99 identifier. |
| 638 | * The "provider" and "name" MUST follow these rules to ensure no |
| 639 | * namespace clash occurs: |
| 640 | * |
| 641 | * For projects (applications and libraries) for which an entity |
| 642 | * specific to the project controls the source code and thus its |
| 643 | * tracepoints (typically with a scope larger than a single company): |
| 644 | * |
| 645 | * either: |
| 646 | * project_component, event |
| 647 | * or: |
| 648 | * project, event |
| 649 | * |
| 650 | * Where "project" is the name of the project, |
| 651 | * "component" is the name of the project component (which may |
| 652 | * include several levels of sub-components, e.g. |
| 653 | * ...component_subcomponent_...) where the tracepoint is located |
| 654 | * (optional), |
| 655 | * "event" is the name of the tracepoint event. |
| 656 | * |
| 657 | * For projects issued from a single company wishing to advertise that |
| 658 | * the company controls the source code and thus the tracepoints, the |
| 659 | * "com_" prefix should be used: |
| 660 | * |
| 661 | * either: |
| 662 | * com_company_project_component, event |
| 663 | * or: |
| 664 | * com_company_project, event |
| 665 | * |
| 666 | * Where "company" is the name of the company, |
| 667 | * "project" is the name of the project, |
| 668 | * "component" is the name of the project component (which may |
| 669 | * include several levels of sub-components, e.g. |
| 670 | * ...component_subcomponent_...) where the tracepoint is located |
| 671 | * (optional), |
| 672 | * "event" is the name of the tracepoint event. |
| 673 | * |
| 674 | * the provider:event identifier is limited to 127 characters. |
| 675 | */ |
| 676 | |
| 677 | #define TRACEPOINT_EVENT(provider, name, args, fields) \ |
| 678 | _DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args)) \ |
| 679 | _DEFINE_TRACEPOINT(provider, name, _TP_PARAMS(args)) |
| 680 | |
| 681 | #define TRACEPOINT_EVENT_CLASS(provider, name, args, fields) |
| 682 | |
| 683 | #define TRACEPOINT_EVENT_INSTANCE(provider, _template, name, args) \ |
| 684 | _DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args)) \ |
| 685 | _DEFINE_TRACEPOINT(provider, name, _TP_PARAMS(args)) |
| 686 | |
| 687 | #endif /* #ifndef TRACEPOINT_EVENT */ |
| 688 | |
| 689 | #ifndef TRACEPOINT_LOGLEVEL |
| 690 | |
| 691 | /* |
| 692 | * Tracepoint Loglevels |
| 693 | * |
| 694 | * Typical use of these loglevels: |
| 695 | * |
| 696 | * The loglevels go from 0 to 14. Higher numbers imply the most |
| 697 | * verbosity (higher event throughput expected. |
| 698 | * |
| 699 | * Loglevels 0 through 6, and loglevel 14, match syslog(3) loglevels |
| 700 | * semantic. Loglevels 7 through 13 offer more fine-grained selection of |
| 701 | * debug information. |
| 702 | * |
| 703 | * TRACE_EMERG 0 |
| 704 | * system is unusable |
| 705 | * |
| 706 | * TRACE_ALERT 1 |
| 707 | * action must be taken immediately |
| 708 | * |
| 709 | * TRACE_CRIT 2 |
| 710 | * critical conditions |
| 711 | * |
| 712 | * TRACE_ERR 3 |
| 713 | * error conditions |
| 714 | * |
| 715 | * TRACE_WARNING 4 |
| 716 | * warning conditions |
| 717 | * |
| 718 | * TRACE_NOTICE 5 |
| 719 | * normal, but significant, condition |
| 720 | * |
| 721 | * TRACE_INFO 6 |
| 722 | * informational message |
| 723 | * |
| 724 | * TRACE_DEBUG_SYSTEM 7 |
| 725 | * debug information with system-level scope (set of programs) |
| 726 | * |
| 727 | * TRACE_DEBUG_PROGRAM 8 |
| 728 | * debug information with program-level scope (set of processes) |
| 729 | * |
| 730 | * TRACE_DEBUG_PROCESS 9 |
| 731 | * debug information with process-level scope (set of modules) |
| 732 | * |
| 733 | * TRACE_DEBUG_MODULE 10 |
| 734 | * debug information with module (executable/library) scope (set of units) |
| 735 | * |
| 736 | * TRACE_DEBUG_UNIT 11 |
| 737 | * debug information with compilation unit scope (set of functions) |
| 738 | * |
| 739 | * TRACE_DEBUG_FUNCTION 12 |
| 740 | * debug information with function-level scope |
| 741 | * |
| 742 | * TRACE_DEBUG_LINE 13 |
| 743 | * debug information with line-level scope (TRACEPOINT_EVENT default) |
| 744 | * |
| 745 | * TRACE_DEBUG 14 |
| 746 | * debug-level message |
| 747 | * |
| 748 | * Declare tracepoint loglevels for tracepoints. A TRACEPOINT_EVENT |
| 749 | * should be declared prior to the the TRACEPOINT_LOGLEVEL for a given |
| 750 | * tracepoint name. The first field is the provider name, the second |
| 751 | * field is the name of the tracepoint, the third field is the loglevel |
| 752 | * name. |
| 753 | * |
| 754 | * TRACEPOINT_LOGLEVEL(< [com_company_]project[_component] >, < event >, |
| 755 | * < loglevel_name >) |
| 756 | * |
| 757 | * The TRACEPOINT_PROVIDER must be already declared before declaring a |
| 758 | * TRACEPOINT_LOGLEVEL. |
| 759 | */ |
| 760 | |
| 761 | enum { |
| 762 | TRACE_EMERG = 0, |
| 763 | TRACE_ALERT = 1, |
| 764 | TRACE_CRIT = 2, |
| 765 | TRACE_ERR = 3, |
| 766 | TRACE_WARNING = 4, |
| 767 | TRACE_NOTICE = 5, |
| 768 | TRACE_INFO = 6, |
| 769 | TRACE_DEBUG_SYSTEM = 7, |
| 770 | TRACE_DEBUG_PROGRAM = 8, |
| 771 | TRACE_DEBUG_PROCESS = 9, |
| 772 | TRACE_DEBUG_MODULE = 10, |
| 773 | TRACE_DEBUG_UNIT = 11, |
| 774 | TRACE_DEBUG_FUNCTION = 12, |
| 775 | TRACE_DEBUG_LINE = 13, |
| 776 | TRACE_DEBUG = 14, |
| 777 | }; |
| 778 | |
| 779 | #define TRACEPOINT_LOGLEVEL(provider, name, loglevel) |
| 780 | |
| 781 | #endif /* #ifndef TRACEPOINT_LOGLEVEL */ |
| 782 | |
| 783 | #ifndef TRACEPOINT_MODEL_EMF_URI |
| 784 | |
| 785 | #define TRACEPOINT_MODEL_EMF_URI(provider, name, uri) |
| 786 | |
| 787 | #endif /* #ifndef TRACEPOINT_MODEL_EMF_URI */ |