X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=include%2Flttng%2Ftracepoint.h;h=1adb149db3994a5dcd40840126bfdef22868cb2b;hb=a334646a99520fdcf81e1460a839cae5c6d06f2c;hp=dc7832cb25531b1912d2e0449976da8a58ce5cd3;hpb=8e90eb06e6106d536519009cb297c479643b4150;p=lttng-ust.git

diff --git a/include/lttng/tracepoint.h b/include/lttng/tracepoint.h
index dc7832cb..1adb149d 100644
--- a/include/lttng/tracepoint.h
+++ b/include/lttng/tracepoint.h
@@ -14,9 +14,11 @@
  * modified is included with the above copyright notice.
  */
 
-#include <urcu-bp.h>
-#include <tracepoint-types.h>
+#include <lttng/tracepoint-types.h>
+#include <lttng/tracepoint-rcu.h>
 #include <urcu/compiler.h>
+#include <dlfcn.h>	/* for dlopen */
+#include <assert.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -36,8 +38,18 @@ extern "C" {
  * fine too).
  * Each tuple is also separated by a comma.
  */
-#define _TP_COMBINE_TOKENS1(_tokena, _tokenb)       _tokena##_tokenb
-#define _TP_COMBINE_TOKENS(_tokena, _tokenb)        _TP_COMBINE_TOKENS1(_tokena, _tokenb)
+#define __TP_COMBINE_TOKENS(_tokena, _tokenb)				\
+		_tokena##_tokenb
+#define _TP_COMBINE_TOKENS(_tokena, _tokenb)				\
+		__TP_COMBINE_TOKENS(_tokena, _tokenb)
+#define __TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc)			\
+		_tokena##_tokenb##_tokenc
+#define _TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc)			\
+		__TP_COMBINE_TOKENS3(_tokena, _tokenb, _tokenc)
+#define __TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend)	\
+		_tokena##_tokenb##_tokenc##_tokend
+#define _TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend)		\
+		__TP_COMBINE_TOKENS4(_tokena, _tokenb, _tokenc, _tokend)
 
 /* _TP_EXVAR* extract the var names. */
 #define _TP_EXVAR0()
@@ -108,8 +120,10 @@ static inline void __tracepoint_cb_##provider##___##name(_TP_ARGS_PROTO(__VA_ARG
 {											\
 	struct tracepoint_probe *__tp_probe;						\
 											\
-	rcu_read_lock_bp();								\
-	__tp_probe = rcu_dereference(__tracepoint_##provider##___##name.probes);	\
+	if (!TP_RCU_LINK_TEST())							\
+		return;									\
+	tp_rcu_read_lock_bp();								\
+	__tp_probe = tp_rcu_dereference_bp(__tracepoint_##provider##___##name.probes);	\
 	if (caa_unlikely(!__tp_probe))							\
 		goto end;								\
 	do {										\
@@ -120,7 +134,7 @@ static inline void __tracepoint_cb_##provider##___##name(_TP_ARGS_PROTO(__VA_ARG
 				(_TP_ARGS_DATA_VAR(__VA_ARGS__));			\
 	} while ((++__tp_probe)->func);							\
 end:											\
-	rcu_read_unlock_bp();								\
+	tp_rcu_read_unlock_bp();							\
 }											\
 static inline void __tracepoint_register_##provider##___##name(char *name,		\
 		void *func, void *data)							\
@@ -133,6 +147,11 @@ static inline void __tracepoint_unregister_##provider##___##name(char *name,		\
 	__tracepoint_probe_unregister(name, func, data);				\
 }
 
+extern int __tracepoint_probe_register(const char *name, void *func, void *data);
+extern int __tracepoint_probe_unregister(const char *name, void *func, void *data);
+
+#ifdef TRACEPOINT_DEFINE
+
 /*
  * Note: to allow PIC code, we need to allow the linker to update the pointers
  * in the __tracepoints_ptrs section.
@@ -149,11 +168,10 @@ static inline void __tracepoint_unregister_##provider##___##name(char *name,		\
 		__attribute__((used, section("__tracepoints_ptrs"))) =		\
 			&__tracepoint_##provider##___##name;
 
-extern int __tracepoint_probe_register(const char *name, void *func, void *data);
-extern int __tracepoint_probe_unregister(const char *name, void *func, void *data);
-extern int tracepoint_register_lib(struct tracepoint * const *tracepoints_start,
+static int (*tracepoint_register_lib)(struct tracepoint * const *tracepoints_start,
 		int tracepoints_count);
-extern int tracepoint_unregister_lib(struct tracepoint * const *tracepoints_start);
+static int (*tracepoint_unregister_lib)(struct tracepoint * const *tracepoints_start);
+static void *liblttngust_handle;
 
 /*
  * These weak symbols, the constructor, and destructor take care of
@@ -171,6 +189,32 @@ static void __attribute__((constructor)) __tracepoints__init(void)
 {
 	if (__tracepoint_registered++)
 		return;
+
+	liblttngust_handle = dlopen("liblttng-ust.so.0", RTLD_NOW | RTLD_GLOBAL);
+	if (!liblttngust_handle)
+		return;
+	tracepoint_register_lib =
+		URCU_FORCE_CAST(int (*)(struct tracepoint * const *, int),
+				dlsym(liblttngust_handle,
+					"tracepoint_register_lib"));
+	tracepoint_unregister_lib =
+		URCU_FORCE_CAST(int (*)(struct tracepoint * const *),
+				dlsym(liblttngust_handle,
+					"tracepoint_unregister_lib"));
+#ifndef _LGPL_SOURCE
+	tp_rcu_read_lock_bp =
+		URCU_FORCE_CAST(void (*)(void),
+				dlsym(liblttngust_handle,
+					"tp_rcu_read_lock_bp"));
+	tp_rcu_read_unlock_bp =
+		URCU_FORCE_CAST(void (*)(void),
+				dlsym(liblttngust_handle,
+					"tp_rcu_read_unlock_bp"));
+	tp_rcu_dereference_sym_bp =
+		URCU_FORCE_CAST(void *(*)(void *p),
+				dlsym(liblttngust_handle,
+					"tp_rcu_dereference_sym_bp"));
+#endif
 	tracepoint_register_lib(__start___tracepoints_ptrs,
 				__stop___tracepoints_ptrs -
 				__start___tracepoints_ptrs);
@@ -178,11 +222,25 @@ static void __attribute__((constructor)) __tracepoints__init(void)
 
 static void __attribute__((destructor)) __tracepoints__destroy(void)
 {
+	int ret;
 	if (--__tracepoint_registered)
 		return;
-	tracepoint_unregister_lib(__start___tracepoints_ptrs);
+	if (tracepoint_unregister_lib)
+		tracepoint_unregister_lib(__start___tracepoints_ptrs);
+	if (liblttngust_handle) {
+		tracepoint_unregister_lib = NULL;
+		tracepoint_register_lib = NULL;
+		ret = dlclose(liblttngust_handle);
+		assert(!ret);
+	}
 }
 
+#else /* TRACEPOINT_DEFINE */
+
+#define _DEFINE_TRACEPOINT(provider, name)
+
+#endif /* #else TRACEPOINT_DEFINE */
+
 #ifdef __cplusplus
 }
 #endif
@@ -273,12 +331,14 @@ static void __attribute__((destructor)) __tracepoints__destroy(void)
  */
 
 #define TRACEPOINT_EVENT(provider, name, args, fields)			\
-	_DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args))
+	_DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args))		\
+	_DEFINE_TRACEPOINT(provider, name)
 
 #define TRACEPOINT_EVENT_CLASS(provider, name, args, fields)
 
 #define TRACEPOINT_EVENT_INSTANCE(provider, _template, name, args)	\
-	_DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args))
+	_DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args))		\
+	_DEFINE_TRACEPOINT(provider, name)
 
 #endif /* #ifndef TRACEPOINT_EVENT */