2 * SPDX-License-Identifier: MIT
4 * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
7 #ifndef _LTTNG_TRACEPOINT_H
8 #define _LTTNG_TRACEPOINT_H
12 #include <lttng/tracepoint-types.h>
13 #include <lttng/tracepoint-rcu.h>
14 #include <urcu/compiler.h>
15 #include <urcu/system.h>
16 #include <dlfcn.h> /* for dlopen */
17 #include <string.h> /* for memset */
18 #include <lttng/ust-config.h> /* for sdt */
19 #include <lttng/ust-compiler.h>
21 #ifdef LTTNG_UST_HAVE_SDT_INTEGRATION
23 * Instead of using SDT_USE_VARIADIC from 'sys/sdt.h', use our own namespaced
24 * macros since the instrumented application might already have included
25 * 'sys/sdt.h' without variadic support.
29 #define _LTTNG_SDT_NARG(...) \
30 __LTTNG_SDT_NARG(__VA_ARGS__, 12,11,10,9,8,7,6,5,4,3,2,1,0)
32 #define __LTTNG_SDT_NARG(_0,_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,_11,_12, N, ...) N
34 #define _LTTNG_SDT_PROBE_N(provider, name, N, ...) \
35 _SDT_PROBE(provider, name, N, (__VA_ARGS__))
37 #define LTTNG_STAP_PROBEV(provider, name, ...) \
38 _LTTNG_SDT_PROBE_N(provider, name, _LTTNG_SDT_NARG(0, ##__VA_ARGS__), ##__VA_ARGS__)
41 #define LTTNG_STAP_PROBEV(...)
48 #define tracepoint_enabled(provider, name) \
49 caa_unlikely(CMM_LOAD_SHARED(__tracepoint_##provider##___##name.state))
51 #define do_tracepoint(provider, name, ...) \
52 __tracepoint_cb_##provider##___##name(__VA_ARGS__)
54 #define tracepoint(provider, name, ...) \
56 LTTNG_STAP_PROBEV(provider, name, ## __VA_ARGS__); \
57 if (tracepoint_enabled(provider, name)) \
58 do_tracepoint(provider, name, __VA_ARGS__); \
61 #define TP_ARGS(...) __VA_ARGS__
64 * TP_ARGS takes tuples of type, argument separated by a comma.
65 * It can take up to 10 tuples (which means that less than 10 tuples is
67 * Each tuple is also separated by a comma.
69 #define __TP_COMBINE_TOKENS(_tokena, _tokenb) \
71 #define _TP_COMBINE_TOKENS(_tokena, _tokenb) \
72 __TP_COMBINE_TOKENS(_tokena, _tokenb)
73 #define __TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc) \
74 _tokena##_tokenb##_tokenc
75 #define _TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc) \
76 __TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc)
77 #define __TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend) \
78 _tokena##_tokenb##_tokenc##_tokend
79 #define _TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend) \
80 __TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend)
83 * _TP_EXVAR* extract the var names.
84 * _TP_EXVAR1 and _TP_EXDATA_VAR1 are needed for -std=c99.
88 #define _TP_EXVAR2(a,b) b
89 #define _TP_EXVAR4(a,b,c,d) b,d
90 #define _TP_EXVAR6(a,b,c,d,e,f) b,d,f
91 #define _TP_EXVAR8(a,b,c,d,e,f,g,h) b,d,f,h
92 #define _TP_EXVAR10(a,b,c,d,e,f,g,h,i,j) b,d,f,h,j
93 #define _TP_EXVAR12(a,b,c,d,e,f,g,h,i,j,k,l) b,d,f,h,j,l
94 #define _TP_EXVAR14(a,b,c,d,e,f,g,h,i,j,k,l,m,n) b,d,f,h,j,l,n
95 #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
96 #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
97 #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
99 #define _TP_EXDATA_VAR0() __tp_data
100 #define _TP_EXDATA_VAR1(a) __tp_data
101 #define _TP_EXDATA_VAR2(a,b) __tp_data,b
102 #define _TP_EXDATA_VAR4(a,b,c,d) __tp_data,b,d
103 #define _TP_EXDATA_VAR6(a,b,c,d,e,f) __tp_data,b,d,f
104 #define _TP_EXDATA_VAR8(a,b,c,d,e,f,g,h) __tp_data,b,d,f,h
105 #define _TP_EXDATA_VAR10(a,b,c,d,e,f,g,h,i,j) __tp_data,b,d,f,h,j
106 #define _TP_EXDATA_VAR12(a,b,c,d,e,f,g,h,i,j,k,l) __tp_data,b,d,f,h,j,l
107 #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
108 #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
109 #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
110 #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
113 * _TP_EXPROTO* extract tuples of type, var.
114 * _TP_EXPROTO1 and _TP_EXDATA_PROTO1 are needed for -std=c99.
116 #define _TP_EXPROTO0() void
117 #define _TP_EXPROTO1(a) void
118 #define _TP_EXPROTO2(a,b) a b
119 #define _TP_EXPROTO4(a,b,c,d) a b,c d
120 #define _TP_EXPROTO6(a,b,c,d,e,f) a b,c d,e f
121 #define _TP_EXPROTO8(a,b,c,d,e,f,g,h) a b,c d,e f,g h
122 #define _TP_EXPROTO10(a,b,c,d,e,f,g,h,i,j) a b,c d,e f,g h,i j
123 #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
124 #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
125 #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
126 #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
127 #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
129 #define _TP_EXDATA_PROTO0() void *__tp_data
130 #define _TP_EXDATA_PROTO1(a) void *__tp_data
131 #define _TP_EXDATA_PROTO2(a,b) void *__tp_data,a b
132 #define _TP_EXDATA_PROTO4(a,b,c,d) void *__tp_data,a b,c d
133 #define _TP_EXDATA_PROTO6(a,b,c,d,e,f) void *__tp_data,a b,c d,e f
134 #define _TP_EXDATA_PROTO8(a,b,c,d,e,f,g,h) void *__tp_data,a b,c d,e f,g h
135 #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
136 #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
137 #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
138 #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
139 #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
140 #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
142 /* Preprocessor trick to count arguments. Inspired from sdt.h. */
143 #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)
144 #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
145 #define _TP_PROTO_N(N, ...) _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXPROTO, N)(__VA_ARGS__))
146 #define _TP_VAR_N(N, ...) _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXVAR, N)(__VA_ARGS__))
147 #define _TP_DATA_PROTO_N(N, ...) _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXDATA_PROTO, N)(__VA_ARGS__))
148 #define _TP_DATA_VAR_N(N, ...) _TP_PARAMS(_TP_COMBINE_TOKENS(_TP_EXDATA_VAR, N)(__VA_ARGS__))
149 #define _TP_ARGS_PROTO(...) _TP_PROTO_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
150 #define _TP_ARGS_VAR(...) _TP_VAR_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
151 #define _TP_ARGS_DATA_PROTO(...) _TP_DATA_PROTO_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
152 #define _TP_ARGS_DATA_VAR(...) _TP_DATA_VAR_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
153 #define _TP_PARAMS(...) __VA_ARGS__
156 * The tracepoint cb is marked always inline so we can distinguish
157 * between caller's ip addresses within the probe using the return
160 #define _DECLARE_TRACEPOINT(_provider, _name, ...) \
161 extern struct lttng_ust_tracepoint __tracepoint_##_provider##___##_name; \
162 static inline __attribute__((always_inline, unused)) lttng_ust_notrace \
163 void __tracepoint_cb_##_provider##___##_name(_TP_ARGS_PROTO(__VA_ARGS__)); \
165 void __tracepoint_cb_##_provider##___##_name(_TP_ARGS_PROTO(__VA_ARGS__)) \
167 struct lttng_ust_tracepoint_probe *__tp_probe; \
169 if (caa_unlikely(!TP_RCU_LINK_TEST())) \
171 tp_rcu_read_lock(); \
172 __tp_probe = tp_rcu_dereference(__tracepoint_##_provider##___##_name.probes); \
173 if (caa_unlikely(!__tp_probe)) \
176 void (*__tp_cb)(void) = __tp_probe->func; \
177 void *__tp_data = __tp_probe->data; \
179 URCU_FORCE_CAST(void (*)(_TP_ARGS_DATA_PROTO(__VA_ARGS__)), __tp_cb) \
180 (_TP_ARGS_DATA_VAR(__VA_ARGS__)); \
181 } while ((++__tp_probe)->func); \
183 tp_rcu_read_unlock(); \
185 static inline lttng_ust_notrace \
186 void __tracepoint_register_##_provider##___##_name(char *name, \
187 void (*func)(void), void *data); \
189 void __tracepoint_register_##_provider##___##_name(char *name, \
190 void (*func)(void), void *data) \
192 __tracepoint_probe_register(name, func, data, \
193 __tracepoint_##_provider##___##_name.signature); \
195 static inline lttng_ust_notrace \
196 void __tracepoint_unregister_##_provider##___##_name(char *name, \
197 void (*func)(void), void *data); \
199 void __tracepoint_unregister_##_provider##___##_name(char *name, \
200 void (*func)(void), void *data) \
202 __tracepoint_probe_unregister(name, func, data); \
205 extern int __tracepoint_probe_register(const char *name
, void (*func
)(void),
206 void *data
, const char *signature
);
207 extern int __tracepoint_probe_unregister(const char *name
, void (*func
)(void),
211 * tracepoint dynamic linkage handling (callbacks). Hidden visibility:
212 * shared across objects in a module/main executable.
214 struct lttng_ust_tracepoint_dlopen
{
215 void *liblttngust_handle
;
217 int (*tracepoint_register_lib
)(struct lttng_ust_tracepoint
* const *tracepoints_start
,
218 int tracepoints_count
);
219 int (*tracepoint_unregister_lib
)(struct lttng_ust_tracepoint
* const *tracepoints_start
);
220 void (*rcu_read_lock_sym
)(void);
221 void (*rcu_read_unlock_sym
)(void);
222 void *(*rcu_dereference_sym
)(void *p
);
225 extern struct lttng_ust_tracepoint_dlopen tracepoint_dlopen
;
226 extern struct lttng_ust_tracepoint_dlopen
*tracepoint_dlopen_ptr
;
229 * These weak symbols, the constructor, and destructor take care of
230 * registering only _one_ instance of the tracepoints per shared-ojbect
231 * (or for the whole main program).
233 int __tracepoint_registered
234 __attribute__((weak
, visibility("hidden")));
235 int __tracepoint_ptrs_registered
236 __attribute__((weak
, visibility("hidden")));
237 struct lttng_ust_tracepoint_dlopen tracepoint_dlopen
238 __attribute__((weak
, visibility("hidden")));
240 * Deal with gcc O1 optimisation issues with weak hidden symbols. gcc
241 * 4.8 and prior does not have the same behavior for symbol scoping on
242 * 32-bit powerpc depending on the object size: symbols for objects of 8
243 * bytes or less have the same address throughout a module, whereas they
244 * have different addresses between compile units for objects larger
245 * than 8 bytes. Add this pointer indirection to ensure that the symbol
246 * scoping match that of the other weak hidden symbols found in this
249 struct lttng_ust_tracepoint_dlopen
*tracepoint_dlopen_ptr
250 __attribute__((weak
, visibility("hidden")));
253 * Tracepoint dynamic linkage handling (callbacks). Hidden visibility: shared
254 * across objects in a module/main executable. The callbacks are used to
255 * control and check if the destructors should be executed.
257 struct lttng_ust_tracepoint_destructors_syms
{
258 void (*tracepoint_disable_destructors
)(void);
259 int (*tracepoint_get_destructors_state
)(void);
262 extern struct lttng_ust_tracepoint_destructors_syms tracepoint_destructors_syms
;
263 extern struct lttng_ust_tracepoint_destructors_syms
*tracepoint_destructors_syms_ptr
;
265 struct lttng_ust_tracepoint_destructors_syms tracepoint_destructors_syms
266 __attribute__((weak
, visibility("hidden")));
267 struct lttng_ust_tracepoint_destructors_syms
*tracepoint_destructors_syms_ptr
268 __attribute__((weak
, visibility("hidden")));
270 static inline void tracepoint_disable_destructors(void)
272 if (!tracepoint_dlopen_ptr
)
273 tracepoint_dlopen_ptr
= &tracepoint_dlopen
;
274 if (!tracepoint_destructors_syms_ptr
)
275 tracepoint_destructors_syms_ptr
= &tracepoint_destructors_syms
;
276 if (tracepoint_dlopen_ptr
->liblttngust_handle
277 && tracepoint_destructors_syms_ptr
->tracepoint_disable_destructors
)
278 tracepoint_destructors_syms_ptr
->tracepoint_disable_destructors();
282 static inline void lttng_ust_notrace
283 __tracepoint__init_urcu_sym(void);
285 __tracepoint__init_urcu_sym(void)
287 if (!tracepoint_dlopen_ptr
)
288 tracepoint_dlopen_ptr
= &tracepoint_dlopen
;
290 * Symbols below are needed by tracepoint call sites and probe
293 if (!tracepoint_dlopen_ptr
->rcu_read_lock_sym
)
294 tracepoint_dlopen_ptr
->rcu_read_lock_sym
=
295 URCU_FORCE_CAST(void (*)(void),
296 dlsym(tracepoint_dlopen_ptr
->liblttngust_handle
,
297 "tp_rcu_read_lock"));
298 if (!tracepoint_dlopen_ptr
->rcu_read_unlock_sym
)
299 tracepoint_dlopen_ptr
->rcu_read_unlock_sym
=
300 URCU_FORCE_CAST(void (*)(void),
301 dlsym(tracepoint_dlopen_ptr
->liblttngust_handle
,
302 "tp_rcu_read_unlock"));
303 if (!tracepoint_dlopen_ptr
->rcu_dereference_sym
)
304 tracepoint_dlopen_ptr
->rcu_dereference_sym
=
305 URCU_FORCE_CAST(void *(*)(void *p
),
306 dlsym(tracepoint_dlopen_ptr
->liblttngust_handle
,
307 "tp_rcu_dereference_sym"));
310 static inline void lttng_ust_notrace
311 __tracepoint__init_urcu_sym(void);
313 __tracepoint__init_urcu_sym(void)
318 static void lttng_ust_notrace
__attribute__((constructor
))
319 __tracepoints__init(void);
321 __tracepoints__init(void)
323 if (__tracepoint_registered
++) {
324 if (!tracepoint_dlopen_ptr
->liblttngust_handle
)
326 __tracepoint__init_urcu_sym();
330 if (!tracepoint_dlopen_ptr
)
331 tracepoint_dlopen_ptr
= &tracepoint_dlopen
;
332 if (!tracepoint_dlopen_ptr
->liblttngust_handle
)
333 tracepoint_dlopen_ptr
->liblttngust_handle
=
334 dlopen("liblttng-ust-tracepoint.so.1", RTLD_NOW
| RTLD_GLOBAL
);
335 if (!tracepoint_dlopen_ptr
->liblttngust_handle
)
337 __tracepoint__init_urcu_sym();
340 static void lttng_ust_notrace
__attribute__((destructor
))
341 __tracepoints__destroy(void);
343 __tracepoints__destroy(void)
347 if (--__tracepoint_registered
)
349 if (!tracepoint_dlopen_ptr
)
350 tracepoint_dlopen_ptr
= &tracepoint_dlopen
;
351 if (!tracepoint_destructors_syms_ptr
)
352 tracepoint_destructors_syms_ptr
= &tracepoint_destructors_syms
;
353 if (!tracepoint_dlopen_ptr
->liblttngust_handle
)
355 if (__tracepoint_ptrs_registered
)
358 * Lookup if destructors must be executed using the new method.
360 if (tracepoint_destructors_syms_ptr
->tracepoint_get_destructors_state
361 && !tracepoint_destructors_syms_ptr
->tracepoint_get_destructors_state()) {
363 * The tracepoint_get_destructors_state symbol was found with
364 * dlsym but its returned value is 0 meaning that destructors
365 * must not be executed.
369 ret
= dlclose(tracepoint_dlopen_ptr
->liblttngust_handle
);
371 fprintf(stderr
, "Error (%d) in dlclose\n", ret
);
374 memset(tracepoint_dlopen_ptr
, 0, sizeof(*tracepoint_dlopen_ptr
));
377 #ifdef TRACEPOINT_DEFINE
380 * These weak symbols, the constructor, and destructor take care of
381 * registering only _one_ instance of the tracepoints per shared-ojbect
382 * (or for the whole main program).
384 extern struct lttng_ust_tracepoint
* const __start___tracepoints_ptrs
[]
385 __attribute__((weak
, visibility("hidden")));
386 extern struct lttng_ust_tracepoint
* const __stop___tracepoints_ptrs
[]
387 __attribute__((weak
, visibility("hidden")));
390 * When TRACEPOINT_PROBE_DYNAMIC_LINKAGE is defined, we do not emit a
391 * unresolved symbol that requires the provider to be linked in. When
392 * TRACEPOINT_PROBE_DYNAMIC_LINKAGE is not defined, we emit an
393 * unresolved symbol that depends on having the provider linked in,
394 * otherwise the linker complains. This deals with use of static
395 * libraries, ensuring that the linker does not remove the provider
396 * object from the executable.
398 #ifdef TRACEPOINT_PROBE_DYNAMIC_LINKAGE
399 #define _TRACEPOINT_UNDEFINED_REF(provider) NULL
400 #else /* TRACEPOINT_PROBE_DYNAMIC_LINKAGE */
401 #define _TRACEPOINT_UNDEFINED_REF(provider) &__tracepoint_provider_##provider
402 #endif /* TRACEPOINT_PROBE_DYNAMIC_LINKAGE */
405 * Note: to allow PIC code, we need to allow the linker to update the pointers
406 * in the __tracepoints_ptrs section.
407 * Therefore, this section is _not_ const (read-only).
409 #define _TP_EXTRACT_STRING(...) #__VA_ARGS__
411 #define _DEFINE_TRACEPOINT(_provider, _name, _args) \
412 extern int __tracepoint_provider_##_provider; \
413 static const char __tp_strtab_##_provider##___##_name[] \
414 __attribute__((section("__tracepoints_strings"))) = \
415 #_provider ":" #_name; \
416 struct lttng_ust_tracepoint __tracepoint_##_provider##___##_name \
417 __attribute__((section("__tracepoints"))) = \
419 __tp_strtab_##_provider##___##_name, \
422 _TRACEPOINT_UNDEFINED_REF(_provider), \
423 _TP_EXTRACT_STRING(_args), \
426 static struct lttng_ust_tracepoint * \
427 __tracepoint_ptr_##_provider##___##_name \
428 __attribute__((section("__tracepoints_ptrs"), used)) \
429 __lttng_ust_variable_attribute_no_sanitize_address = \
430 &__tracepoint_##_provider##___##_name;
432 static void lttng_ust_notrace
__attribute__((constructor
))
433 __tracepoints__ptrs_init(void);
435 __tracepoints__ptrs_init(void)
437 if (__tracepoint_ptrs_registered
++)
439 if (!tracepoint_dlopen_ptr
)
440 tracepoint_dlopen_ptr
= &tracepoint_dlopen
;
441 if (!tracepoint_dlopen_ptr
->liblttngust_handle
)
442 tracepoint_dlopen_ptr
->liblttngust_handle
=
443 dlopen("liblttng-ust-tracepoint.so.1", RTLD_NOW
| RTLD_GLOBAL
);
444 if (!tracepoint_dlopen_ptr
->liblttngust_handle
)
446 if (!tracepoint_destructors_syms_ptr
)
447 tracepoint_destructors_syms_ptr
= &tracepoint_destructors_syms
;
448 tracepoint_dlopen_ptr
->tracepoint_register_lib
=
449 URCU_FORCE_CAST(int (*)(struct lttng_ust_tracepoint
* const *, int),
450 dlsym(tracepoint_dlopen_ptr
->liblttngust_handle
,
451 "tracepoint_register_lib"));
452 tracepoint_dlopen_ptr
->tracepoint_unregister_lib
=
453 URCU_FORCE_CAST(int (*)(struct lttng_ust_tracepoint
* const *),
454 dlsym(tracepoint_dlopen_ptr
->liblttngust_handle
,
455 "tracepoint_unregister_lib"));
456 tracepoint_destructors_syms_ptr
->tracepoint_disable_destructors
=
457 URCU_FORCE_CAST(void (*)(void),
458 dlsym(tracepoint_dlopen_ptr
->liblttngust_handle
,
459 "tp_disable_destructors"));
460 tracepoint_destructors_syms_ptr
->tracepoint_get_destructors_state
=
461 URCU_FORCE_CAST(int (*)(void),
462 dlsym(tracepoint_dlopen_ptr
->liblttngust_handle
,
463 "tp_get_destructors_state"));
464 __tracepoint__init_urcu_sym();
465 if (tracepoint_dlopen_ptr
->tracepoint_register_lib
) {
466 tracepoint_dlopen_ptr
->tracepoint_register_lib(__start___tracepoints_ptrs
,
467 __stop___tracepoints_ptrs
-
468 __start___tracepoints_ptrs
);
472 static void lttng_ust_notrace
__attribute__((destructor
))
473 __tracepoints__ptrs_destroy(void);
475 __tracepoints__ptrs_destroy(void)
479 if (--__tracepoint_ptrs_registered
)
481 if (!tracepoint_dlopen_ptr
)
482 tracepoint_dlopen_ptr
= &tracepoint_dlopen
;
483 if (!tracepoint_destructors_syms_ptr
)
484 tracepoint_destructors_syms_ptr
= &tracepoint_destructors_syms
;
485 if (tracepoint_dlopen_ptr
->tracepoint_unregister_lib
)
486 tracepoint_dlopen_ptr
->tracepoint_unregister_lib(__start___tracepoints_ptrs
);
487 if (tracepoint_dlopen_ptr
->liblttngust_handle
488 && tracepoint_destructors_syms_ptr
->tracepoint_get_destructors_state
489 && tracepoint_destructors_syms_ptr
->tracepoint_get_destructors_state()
490 && !__tracepoint_ptrs_registered
) {
491 ret
= dlclose(tracepoint_dlopen_ptr
->liblttngust_handle
);
493 fprintf(stderr
, "Error (%d) in dlclose\n", ret
);
496 memset(tracepoint_dlopen_ptr
, 0, sizeof(*tracepoint_dlopen_ptr
));
500 #else /* TRACEPOINT_DEFINE */
502 #define _DEFINE_TRACEPOINT(_provider, _name, _args)
504 #endif /* #else TRACEPOINT_DEFINE */
510 #endif /* _LTTNG_TRACEPOINT_H */
512 /* The following declarations must be outside re-inclusion protection. */
514 #ifndef TRACEPOINT_ENUM
517 * Tracepoint Enumerations
519 * The enumeration is a mapping between an integer, or range of integers, and
520 * a string. It can be used to have a more compact trace in cases where the
521 * possible values for a field are limited:
525 * TRACEPOINT_ENUM(someproject_component, enumname,
527 * ctf_enum_value("even", 0)
528 * ctf_enum_value("uneven", 1)
529 * ctf_enum_range("twoto4", 2, 4)
530 * ctf_enum_value("five", 5)
534 * Where "someproject_component" is the name of the component this enumeration
535 * belongs to and "enumname" identifies this enumeration. Inside the
536 * TP_ENUM_VALUES macro is the actual mapping. Each string value can map
537 * to either a single value with ctf_enum_value or a range of values
538 * with ctf_enum_range.
540 * Enumeration ranges may overlap, but the behavior is implementation-defined,
541 * each trace reader will handle overlapping as it wishes.
543 * That enumeration can then be used in a field inside the TP_FIELD macro using
544 * the following line:
546 * ctf_enum(someproject_component, enumname, enumtype, enumfield, enumval)
548 * Where "someproject_component" and "enumname" match those in the
549 * TRACEPOINT_ENUM, "enumtype" is a signed or unsigned integer type
550 * backing the enumeration, "enumfield" is the name of the field and
551 * "enumval" is the value.
554 #define TRACEPOINT_ENUM(provider, name, values)
556 #endif /* #ifndef TRACEPOINT_ENUM */
558 #ifndef TRACEPOINT_EVENT
561 * How to use the TRACEPOINT_EVENT macro:
565 * TRACEPOINT_EVENT(someproject_component, event_name,
567 * * TP_ARGS takes from 0 to 10 "type, field_name" pairs *
569 * TP_ARGS(int, arg0, void *, arg1, char *, string, size_t, strlen,
570 * long *, arg4, size_t, arg4_len),
572 * * TP_FIELDS describes the event payload layout in the trace *
575 * * Integer, printed in base 10 *
576 * ctf_integer(int, field_a, arg0)
578 * * Integer, printed with 0x base 16 *
579 * ctf_integer_hex(unsigned long, field_d, arg1)
582 * ctf_enum(someproject_component, enum_name, int, field_e, arg0)
584 * * Array Sequence, printed as UTF8-encoded array of bytes *
585 * ctf_array_text(char, field_b, string, FIXED_LEN)
586 * ctf_sequence_text(char, field_c, string, size_t, strlen)
588 * * String, printed as UTF8-encoded string *
589 * ctf_string(field_e, string)
591 * * Array sequence of signed integer values *
592 * ctf_array(long, field_f, arg4, FIXED_LEN4)
593 * ctf_sequence(long, field_g, arg4, size_t, arg4_len)
597 * More detailed explanation:
599 * The name of the tracepoint is expressed as a tuple with the provider
600 * and name arguments.
602 * The provider and name should be a proper C99 identifier.
603 * The "provider" and "name" MUST follow these rules to ensure no
604 * namespace clash occurs:
606 * For projects (applications and libraries) for which an entity
607 * specific to the project controls the source code and thus its
608 * tracepoints (typically with a scope larger than a single company):
611 * project_component, event
615 * Where "project" is the name of the project,
616 * "component" is the name of the project component (which may
617 * include several levels of sub-components, e.g.
618 * ...component_subcomponent_...) where the tracepoint is located
620 * "event" is the name of the tracepoint event.
622 * For projects issued from a single company wishing to advertise that
623 * the company controls the source code and thus the tracepoints, the
624 * "com_" prefix should be used:
627 * com_company_project_component, event
629 * com_company_project, event
631 * Where "company" is the name of the company,
632 * "project" is the name of the project,
633 * "component" is the name of the project component (which may
634 * include several levels of sub-components, e.g.
635 * ...component_subcomponent_...) where the tracepoint is located
637 * "event" is the name of the tracepoint event.
639 * the provider:event identifier is limited to 127 characters.
642 #define TRACEPOINT_EVENT(provider, name, args, fields) \
643 _DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args)) \
644 _DEFINE_TRACEPOINT(provider, name, _TP_PARAMS(args))
646 #define TRACEPOINT_EVENT_CLASS(provider, name, args, fields)
648 #define TRACEPOINT_EVENT_INSTANCE(provider, _template, name, args) \
649 _DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args)) \
650 _DEFINE_TRACEPOINT(provider, name, _TP_PARAMS(args))
652 #endif /* #ifndef TRACEPOINT_EVENT */
654 #ifndef TRACEPOINT_LOGLEVEL
657 * Tracepoint Loglevels
659 * Typical use of these loglevels:
661 * The loglevels go from 0 to 14. Higher numbers imply the most
662 * verbosity (higher event throughput expected.
664 * Loglevels 0 through 6, and loglevel 14, match syslog(3) loglevels
665 * semantic. Loglevels 7 through 13 offer more fine-grained selection of
672 * action must be taken immediately
675 * critical conditions
684 * normal, but significant, condition
687 * informational message
689 * TRACE_DEBUG_SYSTEM 7
690 * debug information with system-level scope (set of programs)
692 * TRACE_DEBUG_PROGRAM 8
693 * debug information with program-level scope (set of processes)
695 * TRACE_DEBUG_PROCESS 9
696 * debug information with process-level scope (set of modules)
698 * TRACE_DEBUG_MODULE 10
699 * debug information with module (executable/library) scope (set of units)
701 * TRACE_DEBUG_UNIT 11
702 * debug information with compilation unit scope (set of functions)
704 * TRACE_DEBUG_FUNCTION 12
705 * debug information with function-level scope
707 * TRACE_DEBUG_LINE 13
708 * debug information with line-level scope (TRACEPOINT_EVENT default)
711 * debug-level message
713 * Declare tracepoint loglevels for tracepoints. A TRACEPOINT_EVENT
714 * should be declared prior to the the TRACEPOINT_LOGLEVEL for a given
715 * tracepoint name. The first field is the provider name, the second
716 * field is the name of the tracepoint, the third field is the loglevel
719 * TRACEPOINT_LOGLEVEL(< [com_company_]project[_component] >, < event >,
722 * The TRACEPOINT_PROVIDER must be already declared before declaring a
723 * TRACEPOINT_LOGLEVEL.
734 TRACE_DEBUG_SYSTEM
= 7,
735 TRACE_DEBUG_PROGRAM
= 8,
736 TRACE_DEBUG_PROCESS
= 9,
737 TRACE_DEBUG_MODULE
= 10,
738 TRACE_DEBUG_UNIT
= 11,
739 TRACE_DEBUG_FUNCTION
= 12,
740 TRACE_DEBUG_LINE
= 13,
744 #define TRACEPOINT_LOGLEVEL(provider, name, loglevel)
746 #endif /* #ifndef TRACEPOINT_LOGLEVEL */
748 #ifndef TRACEPOINT_MODEL_EMF_URI
750 #define TRACEPOINT_MODEL_EMF_URI(provider, name, uri)
752 #endif /* #ifndef TRACEPOINT_MODEL_EMF_URI */