* 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" {
* 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()
#define _TP_ARGS_DATA_VAR(...) _TP_DATA_VAR_N(_TP_NARGS(0, ##__VA_ARGS__), ##__VA_ARGS__)
#define _TP_PARAMS(...) __VA_ARGS__
-#define _DECLARE_TRACEPOINT(provider, name, ...) \
-extern struct tracepoint __tracepoint_##provider##___##name; \
-static inline void __tracepoint_cb_##provider##___##name(_TP_ARGS_PROTO(__VA_ARGS__)) \
+#define _DECLARE_TRACEPOINT(_provider, _name, ...) \
+extern struct tracepoint __tracepoint_##_provider##___##_name; \
+static inline void __tracepoint_cb_##_provider##___##_name(_TP_ARGS_PROTO(__VA_ARGS__)) \
{ \
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 { \
(_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, \
+static inline void __tracepoint_register_##_provider##___##_name(char *name, \
void *func, void *data) \
{ \
__tracepoint_probe_register(name, func, data); \
} \
-static inline void __tracepoint_unregister_##provider##___##name(char *name, \
+static inline void __tracepoint_unregister_##_provider##___##_name(char *name, \
void *func, void *data) \
{ \
__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
+
+/*
+ * When TRACEPOINT_PROBE_DYNAMIC_LINKAGE is defined, we do not emit a
+ * unresolved symbol that requires the provider to be linked in. When
+ * TRACEPOINT_PROBE_DYNAMIC_LINKAGE is not defined, we emit an
+ * unresolved symbol that depends on having the provider linked in,
+ * otherwise the linker complains. This deals with use of static
+ * libraries, ensuring that the linker does not remove the provider
+ * object from the executable.
+ */
+#ifdef TRACEPOINT_PROBE_DYNAMIC_LINKAGE
+#define _TRACEPOINT_UNDEFINED_REF(provider)
+#else /* TRACEPOINT_PROBE_DYNAMIC_LINKAGE */
+#define _TRACEPOINT_UNDEFINED_REF(provider) \
+ &__tracepoint_provider_##provider,
+#endif /* TRACEPOINT_PROBE_DYNAMIC_LINKAGE */
+
/*
* Note: to allow PIC code, we need to allow the linker to update the pointers
* in the __tracepoints_ptrs section.
* Therefore, this section is _not_ const (read-only).
*/
#define _DEFINE_TRACEPOINT(provider, name) \
+ extern int __tracepoint_provider_##provider; \
static const char __tp_strtab_##provider##___##name[] \
__attribute__((section("__tracepoints_strings"))) = \
#provider ":" #name; \
struct tracepoint __tracepoint_##provider##___##name \
__attribute__((section("__tracepoints"))) = \
- { __tp_strtab_##provider##___##name, 0, NULL }; \
+ { __tp_strtab_##provider##___##name, 0, NULL, _TRACEPOINT_UNDEFINED_REF(provider) }; \
static struct tracepoint * __tracepoint_ptr_##provider##___##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
{
if (__tracepoint_registered++)
return;
+
+ liblttngust_handle = dlopen("liblttng-ust-tracepoint.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);
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
*/
#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 */
#ifndef TRACEPOINT_LOGLEVEL
/*
- * Tracepoint Loglevel Declaration Facility
- *
- * This is a place-holder the tracepoint loglevel declaration,
- * overridden by the tracer implementation.
+ * Tracepoint Loglevels
*
* Typical use of these loglevels:
*
- * 1) Declare the mapping between loglevel names and an integer values
- * within TRACEPOINT_LOGLEVEL_ENUM, using TP_LOGLEVEL for each tuple.
- * Do _NOT_ add comma (,) nor semicolon (;) between the
- * TRACEPOINT_LOGLEVEL_ENUM entries. Do _NOT_ add comma (,) nor
- * semicolon (;) after the TRACEPOINT_LOGLEVEL_ENUM declaration. The
- * name should be a proper C99 identifier.
- *
- * TRACEPOINT_LOGLEVEL_ENUM(
- * TP_LOGLEVEL( < loglevel_name >, < value > )
- * TP_LOGLEVEL( < loglevel_name >, < value > )
- * ...
- * )
- *
- * e.g.:
- *
- * TRACEPOINT_LOGLEVEL_ENUM(
- * TP_LOGLEVEL(LOG_EMERG, 0)
- * TP_LOGLEVEL(LOG_ALERT, 1)
- * TP_LOGLEVEL(LOG_CRIT, 2)
- * TP_LOGLEVEL(LOG_ERR, 3)
- * TP_LOGLEVEL(LOG_WARNING, 4)
- * TP_LOGLEVEL(LOG_NOTICE, 5)
- * TP_LOGLEVEL(LOG_INFO, 6)
- * TP_LOGLEVEL(LOG_DEBUG, 7)
- * )
- *
- * 2) Then, declare tracepoint loglevels for tracepoints. A
- * TRACEPOINT_EVENT should be declared prior to the the
- * TRACEPOINT_LOGLEVEL for a given tracepoint name. The first field
- * is the name of the tracepoint, the second field is the loglevel
- * name.
+ * The loglevels go from 0 to 14. Higher numbers imply the most
+ * verbosity (higher event throughput expected.
+ *
+ * Loglevels 0 through 6, and loglevel 14, match syslog(3) loglevels
+ * semantic. Loglevels 7 through 13 offer more fine-grained selection of
+ * debug information.
+ *
+ * TRACE_EMERG 0
+ * system is unusable
+ *
+ * TRACE_ALERT 1
+ * action must be taken immediately
+ *
+ * TRACE_CRIT 2
+ * critical conditions
+ *
+ * TRACE_ERR 3
+ * error conditions
+ *
+ * TRACE_WARNING 4
+ * warning conditions
+ *
+ * TRACE_NOTICE 5
+ * normal, but significant, condition
+ *
+ * TRACE_INFO 6
+ * informational message
+ *
+ * TRACE_DEBUG_SYSTEM 7
+ * debug information with system-level scope (set of programs)
+ *
+ * TRACE_DEBUG_PROGRAM 8
+ * debug information with program-level scope (set of processes)
+ *
+ * TRACE_DEBUG_PROCESS 9
+ * debug information with process-level scope (set of modules)
+ *
+ * TRACE_DEBUG_MODULE 10
+ * debug information with module (executable/library) scope (set of units)
+ *
+ * TRACE_DEBUG_UNIT 11
+ * debug information with compilation unit scope (set of functions)
+ *
+ * TRACE_DEBUG_FUNCTION 12
+ * debug information with function-level scope
+ *
+ * TRACE_DEBUG_LINE 13
+ * debug information with line-level scope (TRACEPOINT_EVENT default)
+ *
+ * TRACE_DEBUG 14
+ * debug-level message (trace_printf default)
+ *
+ * Declare tracepoint loglevels for tracepoints. A TRACEPOINT_EVENT
+ * should be declared prior to the the TRACEPOINT_LOGLEVEL for a given
+ * tracepoint name. The first field is the name of the tracepoint, the
+ * second field is the loglevel name.
*
* TRACEPOINT_LOGLEVEL(< [com_company_]project[_component] >, < event >,
* < loglevel_name >)
*
- * The TRACEPOINT_PROVIDER must be defined when declaring a
- * TRACEPOINT_LOGLEVEL_ENUM and TRACEPOINT_LOGLEVEL. The tracepoint
- * loglevel enumeration apply to the entire TRACEPOINT_PROVIDER. Only one
- * tracepoint loglevel enumeration should be declared per tracepoint
- * provider.
+ * The TRACEPOINT_PROVIDER must be already declared before declaring a
+ * TRACEPOINT_LOGLEVEL.
*/
-#define TRACEPOINT_LOGLEVEL_ENUM()
-#define TRACEPOINT_LOGLEVEL(name, loglevel)
+enum {
+ TRACE_EMERG = 0,
+ TRACE_ALERT = 1,
+ TRACE_CRIT = 2,
+ TRACE_ERR = 3,
+ TRACE_WARNING = 4,
+ TRACE_NOTICE = 5,
+ TRACE_INFO = 6,
+ TRACE_DEBUG_SYSTEM = 7,
+ TRACE_DEBUG_PROGRAM = 8,
+ TRACE_DEBUG_PROCESS = 9,
+ TRACE_DEBUG_MODULE = 10,
+ TRACE_DEBUG_UNIT = 11,
+ TRACE_DEBUG_FUNCTION = 12,
+ TRACE_DEBUG_LINE = 13,
+ TRACE_DEBUG = 14,
+};
+
+#define TRACEPOINT_LOGLEVEL(provider, name, loglevel)
#endif /* #ifndef TRACEPOINT_LOGLEVEL */