X-Git-Url: https://git.liburcu.org/?a=blobdiff_plain;f=include%2Fust%2Ftracepoint.h;h=b11d69d7c039ee7454c0151e39b31f4ac5faa61c;hb=332b3a18ea9e3be7ec5d65a4d75c5cf2b6a59525;hp=56c62b0c6d3c884b1a6115cb4984eb9b17cb3de5;hpb=fbca6b624335eef18c8d86194aeb101a720168f4;p=ust.git diff --git a/include/ust/tracepoint.h b/include/ust/tracepoint.h index 56c62b0..b11d69d 100644 --- a/include/ust/tracepoint.h +++ b/include/ust/tracepoint.h @@ -1,14 +1,15 @@ -#ifndef _LINUX_TRACEPOINT_H -#define _LINUX_TRACEPOINT_H +#ifndef _UST_TRACEPOINT_H +#define _UST_TRACEPOINT_H /* * Copyright (C) 2008 Mathieu Desnoyers * Copyright (C) 2009 Pierre-Marc Fournier + * Copyright (C) 2009 Steven Rostedt * * 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 @@ -24,32 +25,38 @@ * Ported to userspace by Pierre-Marc Fournier. */ -//#include -//#include -//#include - -#define _LGPL_SOURCE #include +#include +#include -#include -#include - -struct module; struct tracepoint; +struct tracepoint_probe { + void *func; + void *data; +}; + struct tracepoint { const char *name; /* Tracepoint name */ - DEFINE_IMV(char, state); /* State. */ - void **funcs; -} __attribute__((aligned(32))); /* - * Aligned on 32 bytes because it is - * globally visible and gcc happily - * align these on the structure size. - * Keep in sync with vmlinux.lds.h. - */ - -#define TPPROTO(args...) args -#define TPARGS(args...) args + char state; /* State. */ + 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 @@ -60,91 +67,91 @@ struct tracepoint { */ #define __DO_TRACE(tp, proto, args) \ do { \ - void **it_func; \ + struct tracepoint_probe *__tp_it_probe_ptr; \ + void *__tp_it_func; \ + void *__tp_cb_data; \ \ - rcu_read_lock(); /*ust rcu_read_lock_sched_notrace(); */ \ - it_func = rcu_dereference((tp)->funcs); \ - if (it_func) { \ + rcu_read_lock(); \ + __tp_it_probe_ptr = rcu_dereference((tp)->probes); \ + if (__tp_it_probe_ptr) { \ do { \ - ((void(*)(proto))(*it_func))(args); \ - } while (*(++it_func)); \ + __tp_it_func = __tp_it_probe_ptr->func; \ + __tp_cb_data = __tp_it_probe_ptr->data; \ + ((void(*)(proto))__tp_it_func)(args); \ + } while ((++__tp_it_probe_ptr)->func); \ } \ - rcu_read_unlock(); /*ust rcu_read_unlock_sched_notrace(); */ \ + rcu_read_unlock(); \ } while (0) -#define __CHECK_TRACE(name, generic, proto, args) \ +#define __CHECK_TRACE(name, proto, args) \ do { \ - if (!generic) { \ - if (unlikely(imv_read(__tracepoint_##name.state))) \ - __DO_TRACE(&__tracepoint_##name, \ - TPPROTO(proto), TPARGS(args)); \ - } else { \ - if (unlikely(_imv_read(__tracepoint_##name.state))) \ - __DO_TRACE(&__tracepoint_##name, \ - TPPROTO(proto), TPARGS(args)); \ - } \ + if (unlikely(__tracepoint_##name.state)) \ + __DO_TRACE(&__tracepoint_##name, \ + TP_PROTO(proto), TP_ARGS(args)); \ } while (0) /* * Make sure the alignment of the structure in the __tracepoints section will * not add unwanted padding between the beginning of the section and the * structure. Force alignment to the same alignment as the section start. - * - * The "generic" argument, passed to the declared __trace_##name inline - * function controls which tracepoint enabling mechanism must be used. - * If generic is true, a variable read is used. - * If generic is false, immediate values are used. */ -#define DECLARE_TRACE(name, proto, args) \ +#define __DECLARE_TRACEPOINT(name, proto, args, data_proto, data_args) \ extern struct tracepoint __tracepoint_##name; \ - static inline void trace_##name(proto) \ + static inline void __trace_##name(proto) \ { \ - __CHECK_TRACE(name, 0, TPPROTO(proto), TPARGS(args)); \ + __CHECK_TRACE(name, TP_PROTO(data_proto), \ + TP_ARGS(data_args)); \ } \ - static inline void _trace_##name(proto) \ - { \ - __CHECK_TRACE(name, 1, TPPROTO(proto), TPARGS(args)); \ - } \ - static inline int register_trace_##name(void (*probe)(proto)) \ + 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)(proto)) \ + 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(name) \ +/* + * __tracepoints_ptrs section is not const (read-only) to let the linker update + * the pointer, allowing PIC code. + */ +#define DEFINE_TRACEPOINT_FN(name, reg, unreg) \ static const char __tpstrtab_##name[] \ __attribute__((section("__tracepoints_strings"))) = #name; \ struct tracepoint __tracepoint_##name \ - __attribute__((section("__tracepoints"), aligned(32))) = \ - { __tpstrtab_##name, 0, NULL } + __attribute__((section("__tracepoints"))) = \ + { __tpstrtab_##name, 0, NULL }; \ + static struct tracepoint * __tracepoint_ptr_##name \ + __attribute__((used, section("__tracepoints_ptrs"))) = \ + &__tracepoint_##name; -#define EXPORT_TRACEPOINT_SYMBOL_GPL(name) \ - EXPORT_SYMBOL_GPL(__tracepoint_##name) -#define EXPORT_TRACEPOINT_SYMBOL(name) \ - EXPORT_SYMBOL(__tracepoint_##name) +#define DEFINE_TRACEPOINT(name) \ + DEFINE_TRACEPOINT_FN(name, NULL, NULL) -extern void tracepoint_update_probe_range(struct tracepoint *begin, - struct tracepoint *end); +extern void tracepoint_update_probe_range(struct tracepoint * const *begin, + struct tracepoint * const *end); #else /* !CONFIG_TRACEPOINTS */ -#define DECLARE_TRACE(name, proto, args) \ +#define __DECLARE_TRACEPOINT(name, proto, args) \ static inline void trace_##name(proto) \ { } \ static inline void _trace_##name(proto) \ { } \ - static inline int register_trace_##name(void (*probe)(proto)) \ + static inline int __register_trace_##name(void (*probe)(proto), void *data) \ { \ return -ENOSYS; \ } \ - static inline int unregister_trace_##name(void (*probe)(proto)) \ + static inline int __unregister_trace_##name(void (*probe)(proto), void *data) \ { \ return -ENOSYS; \ } -#define DEFINE_TRACE(name) +#define DEFINE_TRACEPOINT(name) #define EXPORT_TRACEPOINT_SYMBOL_GPL(name) #define EXPORT_TRACEPOINT_SYMBOL(name) @@ -153,34 +160,57 @@ static inline void tracepoint_update_probe_range(struct tracepoint *begin, { } #endif /* CONFIG_TRACEPOINTS */ +/* + * 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_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_TRACEPOINT_NOARGS() passes "void" as the tracepoint prototype + * and "void *__tp_cb_data" as the callback prototype. + * + * DECLARE_TRACEPOINT() passes "proto" as the tracepoint protoype and + * "void *__tp_cb_data, proto" as the callback prototype. + */ +#define DECLARE_TRACEPOINT_NOARGS(name) \ + __DECLARE_TRACEPOINT(name, void, , void *__tp_cb_data, __tp_cb_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)) + /* * Connect a probe to a tracepoint. * Internal API, should not be used directly. */ -extern int tracepoint_probe_register(const char *name, void *probe); +extern int tracepoint_probe_register(const char *name, void *probe, void *data); /* * Disconnect a probe from a tracepoint. * Internal API, should not be used directly. */ -extern int tracepoint_probe_unregister(const char *name, void *probe); +extern int tracepoint_probe_unregister(const char *name, void *probe, void *data); -extern int tracepoint_probe_register_noupdate(const char *name, void *probe); -extern int tracepoint_probe_unregister_noupdate(const char *name, void *probe); +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 { -//ust// struct module *module; struct tracepoint_lib *lib; - struct tracepoint *tracepoint; + struct tracepoint * const *tracepoint; }; 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 **tracepoint, - struct tracepoint *begin, struct tracepoint *end); +extern int tracepoint_get_iter_range(struct tracepoint * const **tracepoint, + struct tracepoint * const *begin, struct tracepoint * const *end); /* * tracepoint_synchronize_unregister must be called between the last tracepoint @@ -193,21 +223,204 @@ static inline void tracepoint_synchronize_unregister(void) } struct tracepoint_lib { - struct tracepoint *tracepoints_start; + struct tracepoint * const *tracepoints_start; int tracepoints_count; - struct list_head list; + struct cds_list_head list; }; -extern int tracepoint_register_lib(struct tracepoint *tracepoints_start, +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 __start___tracepoints[] __attribute__((visibility("hidden"))); \ - extern struct tracepoint __stop___tracepoints[] __attribute__((visibility("hidden"))); \ - static void __attribute__((constructor)) __tracepoints__init(void) \ + 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); \ + } + + +#ifndef TRACEPOINT_EVENT +/* + * 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 TRACEPOINT_EVENT(name : the + * 'subsystem_event' notation is fine. + * + * Think about this whole construct as the + * 'trace_sched_switch() function' from now on. + * + * + * TRACEPOINT_EVENT(sched_switch, + * + * * + * * A function has a regular function arguments + * * prototype, declare it via TP_PROTO(): + * * + * + * TP_PROTO(struct rq *rq, struct task_struct *prev, + * struct task_struct *next), + * + * * + * * Define the call signature of the 'function'. + * * (Design sidenote: we use this instead of a + * * TP_PROTO1/TP_PROTO2/TP_PROTO3 ugliness.) + * * + * + * TP_ARGS(rq, prev, next), + * + * * + * * Fast binary tracing: define the trace record via + * * TP_STRUCT__entry(). 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' + * * + * * __field(pid_t, prev_prid) is equivalent to a standard declariton: + * * + * * pid_t prev_pid; + * * + * * __array(char, prev_comm, TASK_COMM_LEN) is equivalent to: + * * + * * char prev_comm[TASK_COMM_LEN]; + * * + * + * 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 ) + * ), + * + * * + * * 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. + * * + * * Note: this C code will execute every time a trace event + * * happens, on an active tracepoint. + * * + * + * 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; + * ) + * + * * + * * 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 + * TRACEPOINT_EVENT_FN to perform any (un)registration work. + */ + +struct trace_event { + const char *name; + int (*regfunc)(void *data); + int (*unregfunc)(void *data); +}; + +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; +}; + +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); + +extern void trace_event_update_process(void); +extern int is_trace_event_enabled(const char *channel, const char *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 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 * __event_ptrs_dummy \ + __attribute__((used, section("__trace_events_ptrs"))); \ + static void __attribute__((constructor)) \ + __trace_events__init(void) \ + { \ + trace_event_register_lib(__start___trace_events_ptrs, \ + __stop___trace_events_ptrs - \ + __start___trace_events_ptrs); \ + } \ + \ + static void __attribute__((destructor)) \ + __trace_event__destroy(void) \ { \ - tracepoint_register_lib(__start___tracepoints, \ - (((long)__stop___tracepoints)-((long)__start___tracepoints))/sizeof(struct tracepoint)); \ + trace_event_unregister_lib(__start___trace_events_ptrs);\ } -#endif +#define DECLARE_TRACEPOINT_EVENT_CLASS(name, proto, args, tstruct, assign, print) +#define DEFINE_TRACEPOINT_EVENT(template, name, proto, args) \ + DECLARE_TRACEPOINT(name, TP_PARAMS(proto), TP_PARAMS(args)) +#define DEFINE_TRACEPOINT_EVENT_PRINT(template, name, proto, args, print)\ + DECLARE_TRACEPOINT(name, TP_PARAMS(proto), TP_PARAMS(args)) + +#define TRACEPOINT_EVENT(name, proto, args, struct, assign, print) \ + DECLARE_TRACEPOINT(name, TP_PARAMS(proto), TP_PARAMS(args)) +#define TRACEPOINT_EVENT_FN(name, proto, args, struct, \ + assign, print, reg, unreg) \ + DECLARE_TRACEPOINT(name, TP_PARAMS(proto), TP_PARAMS(args)) + +#endif /* ifdef TRACEPOINT_EVENT (see note above) */ + + +#endif /* _UST_TRACEPOINT_H */