X-Git-Url: https://git.lttng.org/?p=ust.git;a=blobdiff_plain;f=include%2Fust%2Ftracepoint.h;h=9463e4072fa6411d054a2c0f74bd7f6b3f9631f2;hp=43c1b46b4a6df4ce0047915af7133e1a44989ac8;hb=2874fee50444405591974a7166313063b315efe1;hpb=b979b3468dc6a9329288f53ce568815617780d9c diff --git a/include/ust/tracepoint.h b/include/ust/tracepoint.h index 43c1b46..9463e40 100644 --- a/include/ust/tracepoint.h +++ b/include/ust/tracepoint.h @@ -8,8 +8,8 @@ * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public - * License as published by the Free Software Foundation; either - * version 2.1 of the License, or (at your option) any later version. + * License as published by the Free Software Foundation; + * version 2.1 of the License. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of @@ -25,11 +25,8 @@ * Ported to userspace by Pierre-Marc Fournier. */ -#define _LGPL_SOURCE #include -#include - -struct tracepoint; +#include struct tracepoint_probe { void *func; @@ -42,24 +39,33 @@ struct tracepoint { struct tracepoint_probe *probes; }; -#define TP_PARAMS(args...) args -#define TP_PROTO(args...) args -#define TP_ARGS(args...) args - /* * Tracepoints should be added to the instrumented code using the * "tracepoint()" macro. */ #define tracepoint(name, args...) __trace_##name(args) -#define register_tracepoint(name, probe, data) \ - __register_trace_##name(probe, data) - -#define unregister_tracepoint(name, probe, data) \ - __unregister_trace_##name(probe, data) - -#define CONFIG_TRACEPOINTS -#ifdef CONFIG_TRACEPOINTS +/* + * Library should be made known to libust by declaring TRACEPOINT_LIB in + * the source file. (Usually at the end of the file, in the outermost + * scope). + */ +#define TRACEPOINT_LIB \ + extern struct tracepoint * const __start___tracepoints_ptrs[] __attribute__((weak, visibility("hidden"))); \ + extern struct tracepoint * const __stop___tracepoints_ptrs[] __attribute__((weak, visibility("hidden"))); \ + static struct tracepoint * __tracepoint_ptr_dummy \ + __attribute__((used, section("__tracepoints_ptrs"))); \ + static void __attribute__((constructor)) __tracepoints__init(void) \ + { \ + tracepoint_register_lib(__start___tracepoints_ptrs, \ + __stop___tracepoints_ptrs - \ + __start___tracepoints_ptrs); \ + } \ + \ + static void __attribute__((destructor)) __tracepoints__destroy(void) \ + { \ + tracepoint_unregister_lib(__start___tracepoints_ptrs); \ + } /* * it_func[0] is never NULL because there is at least one element in the array @@ -83,6 +89,10 @@ struct tracepoint { rcu_read_unlock(); \ } while (0) +#define TP_PARAMS(args...) args +#define TP_PROTO(args...) args +#define TP_ARGS(args...) args + #define __CHECK_TRACE(name, proto, args) \ do { \ if (unlikely(__tracepoint_##name.state)) \ @@ -95,7 +105,7 @@ struct tracepoint { * not add unwanted padding between the beginning of the section and the * structure. Force alignment to the same alignment as the section start. */ -#define __DECLARE_TRACE(name, proto, args, data_proto, data_args) \ +#define __DECLARE_TRACEPOINT(name, proto, args, data_proto, data_args) \ extern struct tracepoint __tracepoint_##name; \ static inline void __trace_##name(proto) \ { \ @@ -105,118 +115,95 @@ struct tracepoint { static inline int \ __register_trace_##name(void (*probe)(data_proto), void *data) \ { \ - return tracepoint_probe_register(#name, (void *)probe, \ + return __tracepoint_probe_register(#name, (void *)probe,\ data); \ \ } \ static inline int \ __unregister_trace_##name(void (*probe)(data_proto), void *data)\ { \ - return tracepoint_probe_unregister(#name, (void *)probe, \ + return __tracepoint_probe_unregister(#name, (void *)probe, \ data); \ - } - -#define DEFINE_TRACE_FN(name, reg, unreg) \ - static const char __tpstrtab_##name[] \ - __attribute__((section("__tracepoints_strings"))) = #name; \ - struct tracepoint __tracepoint_##name \ - __attribute__((section("__tracepoints"))) = \ - { __tpstrtab_##name, 0, NULL }; \ - static struct tracepoint * const __tracepoint_ptr_##name \ - __attribute__((used, section("__tracepoints_ptrs"))) = \ - &__tracepoint_##name; - -#define DEFINE_TRACE(name) \ - DEFINE_TRACE_FN(name, NULL, NULL) - -extern void tracepoint_update_probe_range(struct tracepoint * const *begin, - struct tracepoint * const *end); - -#else /* !CONFIG_TRACEPOINTS */ -#define __DECLARE_TRACE(name, proto, args) \ + } \ + /* \ + * Backward-compatibility API (will be deprecated): \ + * trace_* \ + * register_trace_* \ + * unregister_trace_* \ + */ \ static inline void trace_##name(proto) \ - { } \ - static inline void _trace_##name(proto) \ - { } \ - static inline int __register_trace_##name(void (*probe)(proto), void *data) \ { \ - return -ENOSYS; \ + __CHECK_TRACE(name, TP_PROTO(proto), \ + TP_ARGS(args)); \ } \ - static inline int __unregister_trace_##name(void (*probe)(proto), void *data) \ + static inline int \ + register_trace_##name(void (*probe)(proto)) \ { \ - return -ENOSYS; \ + return __tracepoint_probe_register(#name, (void *)probe,\ + NULL); \ + } \ + static inline int \ + unregister_trace_##name(void (*probe)(proto)) \ + { \ + return __tracepoint_probe_unregister(#name, (void *)probe, \ + NULL); \ } -#define DEFINE_TRACE(name) -#define EXPORT_TRACEPOINT_SYMBOL_GPL(name) -#define EXPORT_TRACEPOINT_SYMBOL(name) - -static inline void tracepoint_update_probe_range(struct tracepoint *begin, - struct tracepoint *end) -{ } -#endif /* CONFIG_TRACEPOINTS */ - /* - * The need for the DECLARE_TRACE_NOARGS() is to handle the prototype + * The need for the _DECLARE_TRACEPOINT_NOARGS() is to handle the prototype * (void). "void" is a special value in a function prototype and can - * not be combined with other arguments. Since the DECLARE_TRACE() + * not be combined with other arguments. Since the DECLARE_TRACEPOINT() * macro adds a data element at the beginning of the prototype, * we need a way to differentiate "(void *data, proto)" from * "(void *data, void)". The second prototype is invalid. * - * DECLARE_TRACE_NOARGS() passes "void" as the tracepoint prototype + * DECLARE_TRACEPOINT_NOARGS() passes "void" as the tracepoint prototype * and "void *__tp_cb_data" as the callback prototype. * - * DECLARE_TRACE() passes "proto" as the tracepoint protoype and + * DECLARE_TRACEPOINT() passes "proto" as the tracepoint protoype and * "void *__tp_cb_data, proto" as the callback prototype. */ -#define DECLARE_TRACE_NOARGS(name) \ - __DECLARE_TRACE(name, void, , void *__tp_cb_data, __tp_cb_data) - -#define DECLARE_TRACE(name, proto, args) \ - __DECLARE_TRACE(name, TP_PARAMS(proto), TP_PARAMS(args),\ - TP_PARAMS(void *__tp_cb_data, proto), \ - TP_PARAMS(__tp_cb_data, args)) +#define _DECLARE_TRACEPOINT_NOARGS(name) \ + __DECLARE_TRACEPOINT(name, void, , void *__tp_cb_data, __tp_cb_data) -/* - * Connect a probe to a tracepoint. - * Internal API, should not be used directly. - */ -extern int tracepoint_probe_register(const char *name, void *probe, void *data); +#define _DECLARE_TRACEPOINT(name, proto, args) \ + __DECLARE_TRACEPOINT(name, TP_PARAMS(proto), TP_PARAMS(args), \ + TP_PARAMS(void *__tp_cb_data, proto), \ + TP_PARAMS(__tp_cb_data, args)) /* - * Disconnect a probe from a tracepoint. - * Internal API, should not be used directly. + * __tracepoints_ptrs section is not const (read-only) to let the linker update + * the pointer, allowing PIC code. */ -extern int tracepoint_probe_unregister(const char *name, void *probe, void *data); +#define _DEFINE_TRACEPOINT(name) \ + static const char __tpstrtab_##name[] \ + __attribute__((section("__tracepoints_strings"))) = #name; \ + struct tracepoint __tracepoint_##name \ + __attribute__((section("__tracepoints"))) = \ + { __tpstrtab_##name, 0, NULL }; \ + static struct tracepoint * __tracepoint_ptr_##name \ + __attribute__((used, section("__tracepoints_ptrs"))) = \ + &__tracepoint_##name; -extern int tracepoint_probe_register_noupdate(const char *name, void *probe, - void *data); -extern int tracepoint_probe_unregister_noupdate(const char *name, void *probe, - void *data); -extern void tracepoint_probe_update_all(void); -struct tracepoint_iter { - struct tracepoint_lib *lib; - struct tracepoint * const *tracepoint; -}; +#define __register_tracepoint(name, probe, data) \ + __register_trace_##name(probe, data) +#define __unregister_tracepoint(name, probe, data) \ + __unregister_trace_##name(probe, data) -extern void tracepoint_iter_start(struct tracepoint_iter *iter); -extern void tracepoint_iter_next(struct tracepoint_iter *iter); -extern void tracepoint_iter_stop(struct tracepoint_iter *iter); -extern void tracepoint_iter_reset(struct tracepoint_iter *iter); -extern int tracepoint_get_iter_range(struct tracepoint * const **tracepoint, - struct tracepoint * const *begin, struct tracepoint * const *end); +/* + * Connect a probe to a tracepoint. + * Internal API. + */ +extern +int __tracepoint_probe_register(const char *name, void *probe, void *data); /* - * tracepoint_synchronize_unregister must be called between the last tracepoint - * probe unregistration and the end of module exit to make sure there is no - * caller executing a probe when it is freed. + * Disconnect a probe from a tracepoint. + * Internal API. */ -static inline void tracepoint_synchronize_unregister(void) -{ -//ust// synchronize_sched(); -} +extern +int __tracepoint_probe_unregister(const char *name, void *probe, void *data); struct tracepoint_lib { struct tracepoint * const *tracepoints_start; @@ -224,43 +211,38 @@ struct tracepoint_lib { struct cds_list_head list; }; -extern int tracepoint_register_lib(struct tracepoint * const *tracepoints_start, - int tracepoints_count); -extern int tracepoint_unregister_lib(struct tracepoint * const *tracepoints_start); - -#define TRACEPOINT_LIB \ - extern struct tracepoint * const __start___tracepoints_ptrs[] __attribute__((weak, visibility("hidden"))); \ - extern struct tracepoint * const __stop___tracepoints_ptrs[] __attribute__((weak, visibility("hidden"))); \ - static struct tracepoint * const __tracepoint_ptr_dummy \ - __attribute__((used, section("__tracepoints_ptrs"))) = NULL; \ - static void __attribute__((constructor)) __tracepoints__init(void) \ - { \ - tracepoint_register_lib(__start___tracepoints_ptrs, \ - __stop___tracepoints_ptrs - \ - __start___tracepoints_ptrs); \ - } \ - \ - static void __attribute__((destructor)) __tracepoints__destroy(void) \ - { \ - tracepoint_unregister_lib(__start___tracepoints_ptrs); \ - } +extern +int tracepoint_register_lib(struct tracepoint * const *tracepoints_start, + int tracepoints_count); +extern +int tracepoint_unregister_lib(struct tracepoint * const *tracepoints_start); +/* + * Backward-compatibility API (will be deprecated): + * DEFINE_TRACE + * DECLARE_TRACE + * register_tracepoint + * unregister_tracepoint + */ +#define DEFINE_TRACE _DEFINE_TRACEPOINT +#define DECLARE_TRACE(name, proto, args) \ + _DECLARE_TRACEPOINT(name, TP_PARAMS(proto), TP_PARAMS(args)) -#ifndef TRACE_EVENT +#ifndef TRACEPOINT_EVENT /* - * For use with the TRACE_EVENT macro: + * For use with the TRACEPOINT_EVENT macro: * * We define a tracepoint, its arguments, its printf format * and its 'fast binary record' layout. * - * Firstly, name your tracepoint via TRACE_EVENT(name : the + * Firstly, name your tracepoint via TRACEPOINT_EVENT(name : the * 'subsystem_event' notation is fine. * * Think about this whole construct as the * 'trace_sched_switch() function' from now on. * * - * TRACE_EVENT(sched_switch, + * TRACEPOINT_EVENT(sched_switch, * * * * * A function has a regular function arguments @@ -280,116 +262,69 @@ extern int tracepoint_unregister_lib(struct tracepoint * const *tracepoints_star * * * * * Fast binary tracing: define the trace record via - * * TP_STRUCT__entry(). You can think about it like a + * * TP_FIELDS(). You can think about it like a * * regular C structure local variable definition. * * * * This is how the trace record is structured and will * * be saved into the ring buffer. These are the fields * * that will be exposed to readers. * * - * * The declared 'local variable' is called '__entry' + * * tp_field(pid_t, prev_pid, prev->pid) is equivalent + * * to a standard declaraton: * * - * * __field(pid_t, prev_prid) is equivalent to a standard declariton: + * * pid_t prev_pid; * * - * * pid_t prev_pid; + * * followed by an assignment: * * - * * __array(char, prev_comm, TASK_COMM_LEN) is equivalent to: + * * prev_pid = prev->pid; * * - * * char prev_comm[TASK_COMM_LEN]; + * * tp_array(char, prev_comm, TASK_COMM_LEN, prev->comm) is + * * equivalent to: * * - * - * TP_STRUCT__entry( - * __array( char, prev_comm, TASK_COMM_LEN ) - * __field( pid_t, prev_pid ) - * __field( int, prev_prio ) - * __array( char, next_comm, TASK_COMM_LEN ) - * __field( pid_t, next_pid ) - * __field( int, next_prio ) - * ), - * + * * char prev_comm[TASK_COMM_LEN]; * * - * * Assign the entry into the trace record, by embedding - * * a full C statement block into TP_fast_assign(). You - * * can refer to the trace record as '__entry' - - * * otherwise you can put arbitrary C code in here. + * * followed by an assignment: * * - * * Note: this C code will execute every time a trace event - * * happens, on an active tracepoint. + * * memcpy(prev_comm, prev->comm, TASK_COMM_LEN); * * * - * TP_fast_assign( - * memcpy(__entry->next_comm, next->comm, TASK_COMM_LEN); - * __entry->prev_pid = prev->pid; - * __entry->prev_prio = prev->prio; - * memcpy(__entry->prev_comm, prev->comm, TASK_COMM_LEN); - * __entry->next_pid = next->pid; - * __entry->next_prio = next->prio; + * TP_FIELDS( + * tp_array(char, prev_comm, TASK_COMM_LEN, prev->comm) + * tp_field(pid_t, prev_pid, prev->pid) + * tp_field(int, prev_prio, prev->prio) + * tp_array(char, next_comm, TASK_COMM_LEN, next->comm) + * tp_field(pid_t, next_pid, next->pid) + * tp_field(int, next_prio, next->prio) * ) - * - * * - * * Formatted output of a trace record via TP_printf(). - * * This is how the tracepoint will appear under debugging - * * of tracepoints. - * * - * * (raw-binary tracing wont actually perform this step.) - * * - * - * TP_printf("task %s:%d [%d] ==> %s:%d [%d]", - * __entry->prev_comm, __entry->prev_pid, __entry->prev_prio, - * __entry->next_comm, __entry->next_pid, __entry->next_prio), - * * ); - * - * This macro construct is thus used for the regular printf format - * tracing setup. - * - * A set of (un)registration functions can be passed to the variant - * TRACE_EVENT_FN to perform any (un)registration work. */ -struct trace_event { - const char *name; - int (*regfunc)(void *data); - int (*unregfunc)(void *data); -}; +#define TRACEPOINT_EVENT(name, proto, args, fields) \ + _DECLARE_TRACEPOINT(name, TP_PARAMS(proto), TP_PARAMS(args)) -struct trace_event_lib { - struct trace_event * const *trace_events_start; - int trace_events_count; - struct cds_list_head list; -}; - -struct trace_event_iter { - struct trace_event_lib *lib; - struct trace_event * const *trace_event; -}; +#define TRACEPOINT_EVENT_CLASS(name, proto, args, fields) +#define TRACEPOINT_EVENT_INSTANCE(template, name, proto, args) \ + _DECLARE_TRACEPOINT(name, TP_PARAMS(proto), TP_PARAMS(args)) -extern void lock_trace_events(void); -extern void unlock_trace_events(void); - -extern void trace_event_iter_start(struct trace_event_iter *iter); -extern void trace_event_iter_next(struct trace_event_iter *iter); -extern void trace_event_iter_reset(struct trace_event_iter *iter); - -extern int trace_event_get_iter_range(struct trace_event * const **trace_event, - struct trace_event * const *begin, - struct trace_event * const *end); +/* + * Declaration of tracepoints that take 0 argument. + */ +#define TRACEPOINT_EVENT_NOARGS(name, fields) \ + _DECLARE_TRACEPOINT_NOARGS(name) -extern void trace_event_update_process(void); -extern int is_trace_event_enabled(const char *channel, const char *name); +#define TRACEPOINT_EVENT_CLASS_NOARGS(name, fields) +#define TRACEPOINT_EVENT_INSTANCE_NOARGS(template, name) \ + _DECLARE_TRACEPOINT_NOARGS(name) -extern int trace_event_register_lib(struct trace_event * const *start_trace_events, - int trace_event_count); -extern int trace_event_unregister_lib(struct trace_event * const *start_trace_events); -#define TRACE_EVENT_LIB \ +#define TRACEPOINT_EVENT_LIB \ extern struct trace_event * const __start___trace_events_ptrs[] \ __attribute__((weak, visibility("hidden"))); \ extern struct trace_event * const __stop___trace_events_ptrs[] \ __attribute__((weak, visibility("hidden"))); \ - static struct trace_event * const __event_ptrs_dummy \ - __attribute__((used, section("__trace_events_ptrs"))) = NULL; \ + static struct trace_event * __event_ptrs_dummy \ + __attribute__((used, section("__trace_events_ptrs"))); \ static void __attribute__((constructor)) \ __trace_events__init(void) \ { \ @@ -404,19 +339,22 @@ extern int trace_event_unregister_lib(struct trace_event * const *start_trace_ev trace_event_unregister_lib(__start___trace_events_ptrs);\ } -#define DECLARE_TRACE_EVENT_CLASS(name, proto, args, tstruct, assign, print) -#define DEFINE_TRACE_EVENT(template, name, proto, args) \ - DECLARE_TRACE(name, TP_PARAMS(proto), TP_PARAMS(args)) -#define DEFINE_TRACE_EVENT_PRINT(template, name, proto, args, print) \ - DECLARE_TRACE(name, TP_PARAMS(proto), TP_PARAMS(args)) +struct trace_event { + const char *name; +}; -#define TRACE_EVENT(name, proto, args, struct, assign, print) \ - DECLARE_TRACE(name, TP_PARAMS(proto), TP_PARAMS(args)) -#define TRACE_EVENT_FN(name, proto, args, struct, \ - assign, print, reg, unreg) \ - DECLARE_TRACE(name, TP_PARAMS(proto), TP_PARAMS(args)) +struct trace_event_lib { + struct trace_event * const *trace_events_start; + int trace_events_count; + struct cds_list_head list; +}; -#endif /* ifdef TRACE_EVENT (see note above) */ +extern +int trace_event_register_lib(struct trace_event * const *start_trace_events, + int trace_event_count); +extern +int trace_event_unregister_lib(struct trace_event * const *start_trace_events); +#endif /* #ifndef TRACEPOINT_EVENT */ #endif /* _UST_TRACEPOINT_H */