X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=include%2Flttng%2Ftracepoint.h;h=b43f8f98458932e3f0c745e73f246a65717df54a;hb=b4f3bc52dcc49a4e9a82d76df0187e7bbebd3e21;hp=831447dd64643dc754ec0aa6ad9cd39a12ce7d36;hpb=deb6e5408bafcab23cdd3e04b080134931d83906;p=lttng-ust.git diff --git a/include/lttng/tracepoint.h b/include/lttng/tracepoint.h index 831447dd..b43f8f98 100644 --- a/include/lttng/tracepoint.h +++ b/include/lttng/tracepoint.h @@ -14,10 +14,20 @@ * modified is included with the above copyright notice. */ -#include -#include +#include +#include #include #include /* for dlopen */ +#include /* for memset */ +#include +#include /* for sdt */ + +#ifdef LTTNG_UST_HAVE_SDT_INTEGRATION +#define SDT_USE_VARIADIC +#include +#else +#define STAP_PROBEV(...) +#endif #ifdef __cplusplus extern "C" { @@ -25,6 +35,7 @@ extern "C" { #define tracepoint(provider, name, ...) \ do { \ + STAP_PROBEV(provider, name, ## __VA_ARGS__); \ if (caa_unlikely(__tracepoint_##provider##___##name.state)) \ __tracepoint_cb_##provider##___##name(__VA_ARGS__); \ } while (0) @@ -37,8 +48,18 @@ 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() @@ -103,16 +124,16 @@ extern "C" { #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; \ \ - if (!rcu_read_lock_bp) \ + if (!TP_RCU_LINK_TEST()) \ return; \ - rcu_read_lock_bp(); \ - __tp_probe = rcu_dereference_bp(__tracepoint_##provider##___##name.probes); \ + tp_rcu_read_lock_bp(); \ + __tp_probe = tp_rcu_dereference_bp(__tracepoint_##_provider##___##_name.probes); \ if (caa_unlikely(!__tp_probe)) \ goto end; \ do { \ @@ -123,14 +144,14 @@ 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, \ +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); \ @@ -139,28 +160,66 @@ static inline void __tracepoint_unregister_##provider##___##name(char *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); +/* + * tracepoint dynamic linkage handling (callbacks). Hidden visibility: + * shared across objects in a module/main executable. + */ +struct tracepoint_dlopen { + void *liblttngust_handle; + + int (*tracepoint_register_lib)(struct tracepoint * const *tracepoints_start, + int tracepoints_count); + int (*tracepoint_unregister_lib)(struct tracepoint * const *tracepoints_start); +#ifndef _LGPL_SOURCE + void (*rcu_read_lock_sym_bp)(void); + void (*rcu_read_unlock_sym_bp)(void); + void *(*rcu_dereference_sym_bp)(void *p); +#endif +}; + +extern struct tracepoint_dlopen tracepoint_dlopen; + #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) NULL +#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) \ - static const char __tp_strtab_##provider##___##name[] \ +#define _TP_EXTRACT_STRING(...) #__VA_ARGS__ + +#define _DEFINE_TRACEPOINT(_provider, _name, _args) \ + extern int __tracepoint_provider_##_provider; \ + static const char __tp_strtab_##_provider##___##_name[] \ __attribute__((section("__tracepoints_strings"))) = \ - #provider ":" #name; \ - struct tracepoint __tracepoint_##provider##___##name \ + #_provider ":" #_name; \ + struct tracepoint __tracepoint_##_provider##___##_name \ __attribute__((section("__tracepoints"))) = \ - { __tp_strtab_##provider##___##name, 0, NULL }; \ - static struct tracepoint * __tracepoint_ptr_##provider##___##name \ + { \ + __tp_strtab_##_provider##___##_name, \ + 0, \ + NULL, \ + _TRACEPOINT_UNDEFINED_REF(_provider), \ + _TP_EXTRACT_STRING(_args), \ + }; \ + static struct tracepoint * __tracepoint_ptr_##_provider##___##_name \ __attribute__((used, section("__tracepoints_ptrs"))) = \ - &__tracepoint_##provider##___##name; - -static int (*tracepoint_register_lib)(struct tracepoint * const *tracepoints_start, - int tracepoints_count); -static int (*tracepoint_unregister_lib)(struct tracepoint * const *tracepoints_start); -static void *liblttngust_handle; + &__tracepoint_##_provider##___##_name; /* * These weak symbols, the constructor, and destructor take care of @@ -173,20 +232,41 @@ extern struct tracepoint * const __stop___tracepoints_ptrs[] __attribute__((weak, visibility("hidden"))); int __tracepoint_registered __attribute__((weak, visibility("hidden"))); +struct tracepoint_dlopen tracepoint_dlopen + __attribute__((weak, visibility("hidden"))); static void __attribute__((constructor)) __tracepoints__init(void) { if (__tracepoint_registered++) return; - liblttngust_handle = dlopen("liblttng-ust.so", RTLD_NOW | RTLD_GLOBAL); - if (!liblttngust_handle) + tracepoint_dlopen.liblttngust_handle = + dlopen("liblttng-ust-tracepoint.so.0", RTLD_NOW | RTLD_GLOBAL); + if (!tracepoint_dlopen.liblttngust_handle) return; - tracepoint_register_lib = dlsym(liblttngust_handle, - "tracepoint_register_lib"); - tracepoint_unregister_lib = dlsym(liblttngust_handle, - "tracepoint_unregister_lib"); - tracepoint_register_lib(__start___tracepoints_ptrs, + tracepoint_dlopen.tracepoint_register_lib = + URCU_FORCE_CAST(int (*)(struct tracepoint * const *, int), + dlsym(tracepoint_dlopen.liblttngust_handle, + "tracepoint_register_lib")); + tracepoint_dlopen.tracepoint_unregister_lib = + URCU_FORCE_CAST(int (*)(struct tracepoint * const *), + dlsym(tracepoint_dlopen.liblttngust_handle, + "tracepoint_unregister_lib")); +#ifndef _LGPL_SOURCE + tracepoint_dlopen.rcu_read_lock_sym_bp = + URCU_FORCE_CAST(void (*)(void), + dlsym(tracepoint_dlopen.liblttngust_handle, + "tp_rcu_read_lock_bp")); + tracepoint_dlopen.rcu_read_unlock_sym_bp = + URCU_FORCE_CAST(void (*)(void), + dlsym(tracepoint_dlopen.liblttngust_handle, + "tp_rcu_read_unlock_bp")); + tracepoint_dlopen.rcu_dereference_sym_bp = + URCU_FORCE_CAST(void *(*)(void *p), + dlsym(tracepoint_dlopen.liblttngust_handle, + "tp_rcu_dereference_sym_bp")); +#endif + tracepoint_dlopen.tracepoint_register_lib(__start___tracepoints_ptrs, __stop___tracepoints_ptrs - __start___tracepoints_ptrs); } @@ -194,21 +274,21 @@ static void __attribute__((constructor)) __tracepoints__init(void) static void __attribute__((destructor)) __tracepoints__destroy(void) { int ret; + if (--__tracepoint_registered) return; - 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); + if (tracepoint_dlopen.tracepoint_unregister_lib) + tracepoint_dlopen.tracepoint_unregister_lib(__start___tracepoints_ptrs); + if (tracepoint_dlopen.liblttngust_handle) { + ret = dlclose(tracepoint_dlopen.liblttngust_handle); assert(!ret); + memset(&tracepoint_dlopen, 0, sizeof(tracepoint_dlopen)); } } #else /* TRACEPOINT_DEFINE */ -#define _DEFINE_TRACEPOINT(provider, name) +#define _DEFINE_TRACEPOINT(_provider, _name, _args) #endif /* #else TRACEPOINT_DEFINE */ @@ -303,70 +383,106 @@ static void __attribute__((destructor)) __tracepoints__destroy(void) #define TRACEPOINT_EVENT(provider, name, args, fields) \ _DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args)) \ - _DEFINE_TRACEPOINT(provider, name) + _DEFINE_TRACEPOINT(provider, name, _TP_PARAMS(args)) #define TRACEPOINT_EVENT_CLASS(provider, name, args, fields) #define TRACEPOINT_EVENT_INSTANCE(provider, _template, name, args) \ _DECLARE_TRACEPOINT(provider, name, _TP_PARAMS(args)) \ - _DEFINE_TRACEPOINT(provider, name) + _DEFINE_TRACEPOINT(provider, name, _TP_PARAMS(args)) #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 - * tp_loglevel entries contained within TRACEPOINT_LOGLEVEL_ENUM(). - * 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 provider name, the second + * field is the name of the tracepoint, the third 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(...) +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 */