#ifndef _LINUX_FTRACE_EVENT_H #define _LINUX_FTRACE_EVENT_H #include #include #include #include #include struct trace_array; struct trace_buffer; struct tracer; struct dentry; struct trace_print_flags { unsigned long mask; const char *name; }; struct trace_print_flags_u64 { unsigned long long mask; const char *name; }; const char *ftrace_print_flags_seq(struct trace_seq *p, const char *delim, unsigned long flags, const struct trace_print_flags *flag_array); const char *ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val, const struct trace_print_flags *symbol_array); #if BITS_PER_LONG == 32 const char *ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val, const struct trace_print_flags_u64 *symbol_array); #endif const char *ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int len); struct trace_iterator; struct trace_event; int ftrace_raw_output_prep(struct trace_iterator *iter, struct trace_event *event); /* * The trace entry - the most basic unit of tracing. This is what * is printed in the end as a single line in the trace output, such as: * * bash-15816 [01] 235.197585: idle_cpu <- irq_enter */ struct trace_entry { unsigned short type; unsigned char flags; unsigned char preempt_count; int pid; }; #define FTRACE_MAX_EVENT \ ((1 << (sizeof(((struct trace_entry *)0)->type) * 8)) - 1) /* * Trace iterator - used by printout routines who present trace * results to users and which routines might sleep, etc: */ struct trace_iterator { struct trace_array *tr; struct tracer *trace; struct trace_buffer *trace_buffer; void *private; int cpu_file; struct mutex mutex; struct ring_buffer_iter **buffer_iter; unsigned long iter_flags; /* trace_seq for __print_flags() and __print_symbolic() etc. */ struct trace_seq tmp_seq; cpumask_var_t started; /* it's true when current open file is snapshot */ bool snapshot; /* The below is zeroed out in pipe_read */ struct trace_seq seq; struct trace_entry *ent; unsigned long lost_events; int leftover; int ent_size; int cpu; u64 ts; loff_t pos; long idx; /* All new field here will be zeroed out in pipe_read */ }; enum trace_iter_flags { TRACE_FILE_LAT_FMT = 1, TRACE_FILE_ANNOTATE = 2, TRACE_FILE_TIME_IN_NS = 4, }; typedef enum print_line_t (*trace_print_func)(struct trace_iterator *iter, int flags, struct trace_event *event); struct trace_event_functions { trace_print_func trace; trace_print_func raw; trace_print_func hex; trace_print_func binary; }; struct trace_event { struct hlist_node node; struct list_head list; int type; struct trace_event_functions *funcs; }; extern int register_ftrace_event(struct trace_event *event); extern int unregister_ftrace_event(struct trace_event *event); /* Return values for print_line callback */ enum print_line_t { TRACE_TYPE_PARTIAL_LINE = 0, /* Retry after flushing the seq */ TRACE_TYPE_HANDLED = 1, TRACE_TYPE_UNHANDLED = 2, /* Relay to other output functions */ TRACE_TYPE_NO_CONSUME = 3 /* Handled but ask to not consume */ }; void tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, int pc); struct ftrace_event_file; struct ring_buffer_event * trace_event_buffer_lock_reserve(struct ring_buffer **current_buffer, struct ftrace_event_file *ftrace_file, int type, unsigned long len, unsigned long flags, int pc); struct ring_buffer_event * trace_current_buffer_lock_reserve(struct ring_buffer **current_buffer, int type, unsigned long len, unsigned long flags, int pc); void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event, unsigned long flags, int pc); void trace_buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event, unsigned long flags, int pc); void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, struct ring_buffer_event *event, unsigned long flags, int pc, struct pt_regs *regs); void trace_current_buffer_discard_commit(struct ring_buffer *buffer, struct ring_buffer_event *event); void tracing_record_cmdline(struct task_struct *tsk); int ftrace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...); struct event_filter; enum trace_reg { TRACE_REG_REGISTER, TRACE_REG_UNREGISTER, #ifdef CONFIG_PERF_EVENTS TRACE_REG_PERF_REGISTER, TRACE_REG_PERF_UNREGISTER, TRACE_REG_PERF_OPEN, TRACE_REG_PERF_CLOSE, TRACE_REG_PERF_ADD, TRACE_REG_PERF_DEL, #endif }; struct ftrace_event_call; struct ftrace_event_class { char *system; void *probe; #ifdef CONFIG_PERF_EVENTS void *perf_probe; #endif int (*reg)(struct ftrace_event_call *event, enum trace_reg type, void *data); int (*define_fields)(struct ftrace_event_call *); struct list_head *(*get_fields)(struct ftrace_event_call *); struct list_head fields; int (*raw_init)(struct ftrace_event_call *); }; extern int ftrace_event_reg(struct ftrace_event_call *event, enum trace_reg type, void *data); int ftrace_output_event(struct trace_iterator *iter, struct ftrace_event_call *event, char *fmt, ...); int ftrace_event_define_field(struct ftrace_event_call *call, char *type, int len, char *item, int offset, int field_size, int sign, int filter); enum { TRACE_EVENT_FL_FILTERED_BIT, TRACE_EVENT_FL_CAP_ANY_BIT, TRACE_EVENT_FL_NO_SET_FILTER_BIT, TRACE_EVENT_FL_IGNORE_ENABLE_BIT, TRACE_EVENT_FL_WAS_ENABLED_BIT, TRACE_EVENT_FL_USE_CALL_FILTER_BIT, }; /* * Event flags: * FILTERED - The event has a filter attached * CAP_ANY - Any user can enable for perf * NO_SET_FILTER - Set when filter has error and is to be ignored * IGNORE_ENABLE - For ftrace internal events, do not enable with debugfs file * WAS_ENABLED - Set and stays set when an event was ever enabled * (used for module unloading, if a module event is enabled, * it is best to clear the buffers that used it). * USE_CALL_FILTER - For ftrace internal events, don't use file filter */ enum { TRACE_EVENT_FL_FILTERED = (1 << TRACE_EVENT_FL_FILTERED_BIT), TRACE_EVENT_FL_CAP_ANY = (1 << TRACE_EVENT_FL_CAP_ANY_BIT), TRACE_EVENT_FL_NO_SET_FILTER = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT), TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT), TRACE_EVENT_FL_WAS_ENABLED = (1 << TRACE_EVENT_FL_WAS_ENABLED_BIT), TRACE_EVENT_FL_USE_CALL_FILTER = (1 << TRACE_EVENT_FL_USE_CALL_FILTER_BIT), }; struct ftrace_event_call { struct list_head list; struct ftrace_event_class *class; char *name; struct trace_event event; const char *print_fmt; struct event_filter *filter; struct list_head *files; void *mod; void *data; /* * bit 0: filter_active * bit 1: allow trace by non root (cap any) * bit 2: failed to apply filter * bit 3: ftrace internal event (do not enable) * bit 4: Event was enabled by module * bit 5: use call filter rather than file filter */ int flags; /* static flags of different events */ #ifdef CONFIG_PERF_EVENTS int perf_refcount; struct hlist_head __percpu *perf_events; int (*perf_perm)(struct ftrace_event_call *, struct perf_event *); #endif }; struct trace_array; struct ftrace_subsystem_dir; enum { FTRACE_EVENT_FL_ENABLED_BIT, FTRACE_EVENT_FL_RECORDED_CMD_BIT, FTRACE_EVENT_FL_FILTERED_BIT, FTRACE_EVENT_FL_NO_SET_FILTER_BIT, FTRACE_EVENT_FL_SOFT_MODE_BIT, FTRACE_EVENT_FL_SOFT_DISABLED_BIT, FTRACE_EVENT_FL_TRIGGER_MODE_BIT, FTRACE_EVENT_FL_TRIGGER_COND_BIT, }; /* * Ftrace event file flags: * ENABLED - The event is enabled * RECORDED_CMD - The comms should be recorded at sched_switch * FILTERED - The event has a filter attached * NO_SET_FILTER - Set when filter has error and is to be ignored * SOFT_MODE - The event is enabled/disabled by SOFT_DISABLED * SOFT_DISABLED - When set, do not trace the event (even though its * tracepoint may be enabled) * TRIGGER_MODE - When set, invoke the triggers associated with the event * TRIGGER_COND - When set, one or more triggers has an associated filter */ enum { FTRACE_EVENT_FL_ENABLED = (1 << FTRACE_EVENT_FL_ENABLED_BIT), FTRACE_EVENT_FL_RECORDED_CMD = (1 << FTRACE_EVENT_FL_RECORDED_CMD_BIT), FTRACE_EVENT_FL_FILTERED = (1 << FTRACE_EVENT_FL_FILTERED_BIT), FTRACE_EVENT_FL_NO_SET_FILTER = (1 << FTRACE_EVENT_FL_NO_SET_FILTER_BIT), FTRACE_EVENT_FL_SOFT_MODE = (1 << FTRACE_EVENT_FL_SOFT_MODE_BIT), FTRACE_EVENT_FL_SOFT_DISABLED = (1 << FTRACE_EVENT_FL_SOFT_DISABLED_BIT), FTRACE_EVENT_FL_TRIGGER_MODE = (1 << FTRACE_EVENT_FL_TRIGGER_MODE_BIT), FTRACE_EVENT_FL_TRIGGER_COND = (1 << FTRACE_EVENT_FL_TRIGGER_COND_BIT), }; struct ftrace_event_file { struct list_head list; struct ftrace_event_call *event_call; struct event_filter *filter; struct dentry *dir; struct trace_array *tr; struct ftrace_subsystem_dir *system; struct list_head triggers; /* * 32 bit flags: * bit 0: enabled * bit 1: enabled cmd record * bit 2: enable/disable with the soft disable bit * bit 3: soft disabled * bit 4: trigger enabled * * Note: The bits must be set atomically to prevent races * from other writers. Reads of flags do not need to be in * sync as they occur in critical sections. But the way flags * is currently used, these changes do not affect the code * except that when a change is made, it may have a slight * delay in propagating the changes to other CPUs due to * caching and such. Which is mostly OK ;-) */ unsigned long flags; atomic_t sm_ref; /* soft-mode reference counter */ atomic_t tm_ref; /* trigger-mode reference counter */ }; #define __TRACE_EVENT_FLAGS(name, value) \ static int __init trace_init_flags_##name(void) \ { \ event_##name.flags = value; \ return 0; \ } \ early_initcall(trace_init_flags_##name); #define __TRACE_EVENT_PERF_PERM(name, expr...) \ static int perf_perm_##name(struct ftrace_event_call *tp_event, \ struct perf_event *p_event) \ { \ return ({ expr; }); \ } \ static int __init trace_init_perf_perm_##name(void) \ { \ event_##name.perf_perm = &perf_perm_##name; \ return 0; \ } \ early_initcall(trace_init_perf_perm_##name); #define PERF_MAX_TRACE_SIZE 2048 #define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */ enum event_trigger_type { ETT_NONE = (0), ETT_TRACE_ONOFF = (1 << 0), ETT_SNAPSHOT = (1 << 1), ETT_STACKTRACE = (1 << 2), ETT_EVENT_ENABLE = (1 << 3), }; extern void destroy_preds(struct ftrace_event_file *file); extern void destroy_call_preds(struct ftrace_event_call *call); extern int filter_match_preds(struct event_filter *filter, void *rec); extern int filter_check_discard(struct ftrace_event_file *file, void *rec, struct ring_buffer *buffer, struct ring_buffer_event *event); extern int call_filter_check_discard(struct ftrace_event_call *call, void *rec, struct ring_buffer *buffer, struct ring_buffer_event *event); extern enum event_trigger_type event_triggers_call(struct ftrace_event_file *file, void *rec); extern void event_triggers_post_call(struct ftrace_event_file *file, enum event_trigger_type tt); /** * ftrace_trigger_soft_disabled - do triggers and test if soft disabled * @file: The file pointer of the event to test * * If any triggers without filters are attached to this event, they * will be called here. If the event is soft disabled and has no * triggers that require testing the fields, it will return true, * otherwise false. */ static inline bool ftrace_trigger_soft_disabled(struct ftrace_event_file *file) { unsigned long eflags = file->flags; if (!(eflags & FTRACE_EVENT_FL_TRIGGER_COND)) { if (eflags & FTRACE_EVENT_FL_TRIGGER_MODE) event_triggers_call(file, NULL); if (eflags & FTRACE_EVENT_FL_SOFT_DISABLED) return true; } return false; } /* * Helper function for event_trigger_unlock_commit{_regs}(). * If there are event triggers attached to this event that requires * filtering against its fields, then they wil be called as the * entry already holds the field information of the current event. * * It also checks if the event should be discarded or not. * It is to be discarded if the event is soft disabled and the * event was only recorded to process triggers, or if the event * filter is active and this event did not match the filters. * * Returns true if the event is discarded, false otherwise. */ static inline bool __event_trigger_test_discard(struct ftrace_event_file *file, struct ring_buffer *buffer, struct ring_buffer_event *event, void *entry, enum event_trigger_type *tt) { unsigned long eflags = file->flags; if (eflags & FTRACE_EVENT_FL_TRIGGER_COND) *tt = event_triggers_call(file, entry); if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &file->flags)) ring_buffer_discard_commit(buffer, event); else if (!filter_check_discard(file, entry, buffer, event)) return false; return true; } /** * event_trigger_unlock_commit - handle triggers and finish event commit * @file: The file pointer assoctiated to the event * @buffer: The ring buffer that the event is being written to * @event: The event meta data in the ring buffer * @entry: The event itself * @irq_flags: The state of the interrupts at the start of the event * @pc: The state of the preempt count at the start of the event. * * This is a helper function to handle triggers that require data * from the event itself. It also tests the event against filters and * if the event is soft disabled and should be discarded. */ static inline void event_trigger_unlock_commit(struct ftrace_event_file *file, struct ring_buffer *buffer, struct ring_buffer_event *event, void *entry, unsigned long irq_flags, int pc) { enum event_trigger_type tt = ETT_NONE; if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) trace_buffer_unlock_commit(buffer, event, irq_flags, pc); if (tt) event_triggers_post_call(file, tt); } /** * event_trigger_unlock_commit_regs - handle triggers and finish event commit * @file: The file pointer assoctiated to the event * @buffer: The ring buffer that the event is being written to * @event: The event meta data in the ring buffer * @entry: The event itself * @irq_flags: The state of the interrupts at the start of the event * @pc: The state of the preempt count at the start of the event. * * This is a helper function to handle triggers that require data * from the event itself. It also tests the event against filters and * if the event is soft disabled and should be discarded. * * Same as event_trigger_unlock_commit() but calls * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit(). */ static inline void event_trigger_unlock_commit_regs(struct ftrace_event_file *file, struct ring_buffer *buffer, struct ring_buffer_event *event, void *entry, unsigned long irq_flags, int pc, struct pt_regs *regs) { enum event_trigger_type tt = ETT_NONE; if (!__event_trigger_test_discard(file, buffer, event, entry, &tt)) trace_buffer_unlock_commit_regs(buffer, event, irq_flags, pc, regs); if (tt) event_triggers_post_call(file, tt); } enum { FILTER_OTHER = 0, FILTER_STATIC_STRING, FILTER_DYN_STRING, FILTER_PTR_STRING, FILTER_TRACE_FN, }; extern int trace_event_raw_init(struct ftrace_event_call *call); extern int trace_define_field(struct ftrace_event_call *call, const char *type, const char *name, int offset, int size, int is_signed, int filter_type); extern int trace_add_event_call(struct ftrace_event_call *call); extern int trace_remove_event_call(struct ftrace_event_call *call); #define is_signed_type(type) (((type)(-1)) < (type)1) int trace_set_clr_event(const char *system, const char *event, int set); /* * The double __builtin_constant_p is because gcc will give us an error * if we try to allocate the static variable to fmt if it is not a * constant. Even with the outer if statement optimizing out. */ #define event_trace_printk(ip, fmt, args...) \ do { \ __trace_printk_check_format(fmt, ##args); \ tracing_record_cmdline(current); \ if (__builtin_constant_p(fmt)) { \ static const char *trace_printk_fmt \ __attribute__((section("__trace_printk_fmt"))) = \ __builtin_constant_p(fmt) ? fmt : NULL; \ \ __trace_bprintk(ip, trace_printk_fmt, ##args); \ } else \ __trace_printk(ip, fmt, ##args); \ } while (0) /** * tracepoint_string - register constant persistent string to trace system * @str - a constant persistent string that will be referenced in tracepoints * * If constant strings are being used in tracepoints, it is faster and * more efficient to just save the pointer to the string and reference * that with a printf "%s" instead of saving the string in the ring buffer * and wasting space and time. * * The problem with the above approach is that userspace tools that read * the binary output of the trace buffers do not have access to the string. * Instead they just show the address of the string which is not very * useful to users. * * With tracepoint_string(), the string will be registered to the tracing * system and exported to userspace via the debugfs/tracing/printk_formats * file that maps the string address to the string text. This way userspace * tools that read the binary buffers have a way to map the pointers to * the ASCII strings they represent. * * The @str used must be a constant string and persistent as it would not * make sense to show a string that no longer exists. But it is still fine * to be used with modules, because when modules are unloaded, if they * had tracepoints, the ring buffers are cleared too. As long as the string * does not change during the life of the module, it is fine to use * tracepoint_string() within a module. */ #define tracepoint_string(str) \ ({ \ static const char *___tp_str __tracepoint_string = str; \ ___tp_str; \ }) #define __tracepoint_string __attribute__((section("__tracepoint_str"))) #ifdef CONFIG_PERF_EVENTS struct perf_event; DECLARE_PER_CPU(struct pt_regs, perf_trace_regs); extern int perf_trace_init(struct perf_event *event); extern void perf_trace_destroy(struct perf_event *event); extern int perf_trace_add(struct perf_event *event, int flags); extern void perf_trace_del(struct perf_event *event, int flags); extern int ftrace_profile_set_filter(struct perf_event *event, int event_id, char *filter_str); extern void ftrace_profile_free_filter(struct perf_event *event); extern void *perf_trace_buf_prepare(int size, unsigned short type, struct pt_regs *regs, int *rctxp); static inline void perf_trace_buf_submit(void *raw_data, int size, int rctx, u64 addr, u64 count, struct pt_regs *regs, void *head, struct task_struct *task) { perf_tp_event(addr, count, raw_data, size, regs, head, rctx, task); } #endif #endif /* _LINUX_FTRACE_EVENT_H */