- 根目录:
- include
- linux
- trace_events.h
#ifndef _LINUX_TRACE_EVENT_H
#define _LINUX_TRACE_EVENT_H
#include <linux/ring_buffer.h>
#include <linux/trace_seq.h>
#include <linux/percpu.h>
#include <linux/hardirq.h>
#include <linux/perf_event.h>
#include <linux/tracepoint.h>
struct trace_array;
struct trace_buffer;
struct tracer;
struct dentry;
struct bpf_prog;
struct trace_print_flags {
unsigned long mask;
const char *name;
};
struct trace_print_flags_u64 {
unsigned long long mask;
const char *name;
};
const char *trace_print_flags_seq(struct trace_seq *p, const char *delim,
unsigned long flags,
const struct trace_print_flags *flag_array);
const char *trace_print_symbols_seq(struct trace_seq *p, unsigned long val,
const struct trace_print_flags *symbol_array);
#if BITS_PER_LONG == 32
const char *trace_print_symbols_seq_u64(struct trace_seq *p,
unsigned long long val,
const struct trace_print_flags_u64
*symbol_array);
#endif
const char *trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
unsigned int bitmask_size);
const char *trace_print_hex_seq(struct trace_seq *p,
const unsigned char *buf, int len);
const char *trace_print_array_seq(struct trace_seq *p,
const void *buf, int count,
size_t el_size);
struct trace_iterator;
struct trace_event;
int trace_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 TRACE_EVENT_TYPE_MAX \
((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_trace_event(struct trace_event *event);
extern int unregister_trace_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 */
};
/*
* Several functions return TRACE_TYPE_PARTIAL_LINE if the trace_seq
* overflowed, and TRACE_TYPE_HANDLED otherwise. This helper function
* simplifies those functions and keeps them in sync.
*/
static inline enum print_line_t trace_handle_return(struct trace_seq *s)
{
return trace_seq_has_overflowed(s) ?
TRACE_TYPE_PARTIAL_LINE : TRACE_TYPE_HANDLED;
}
void tracing_generic_entry_update(struct trace_entry *entry,
unsigned long flags,
int pc);
struct trace_event_file;
struct ring_buffer_event *
trace_event_buffer_lock_reserve(struct ring_buffer **current_buffer,
struct trace_event_file *trace_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_buffer_unlock_commit(struct trace_array *tr,
struct ring_buffer *buffer,
struct ring_buffer_event *event,
unsigned long flags, int pc);
void trace_buffer_unlock_commit_regs(struct trace_array *tr,
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 trace_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 trace_event_call;
struct trace_event_class {
const char *system;
void *probe;
#ifdef CONFIG_PERF_EVENTS
void *perf_probe;
#endif
int (*reg)(struct trace_event_call *event,
enum trace_reg type, void *data);
int (*define_fields)(struct trace_event_call *);
struct list_head *(*get_fields)(struct trace_event_call *);
struct list_head fields;
int (*raw_init)(struct trace_event_call *);
};
extern int trace_event_reg(struct trace_event_call *event,
enum trace_reg type, void *data);
struct trace_event_buffer {
struct ring_buffer *buffer;
struct ring_buffer_event *event;
struct trace_event_file *trace_file;
void *entry;
unsigned long flags;
int pc;
};
void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer,
struct trace_event_file *trace_file,
unsigned long len);
void trace_event_buffer_commit(struct trace_event_buffer *fbuffer);
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,
TRACE_EVENT_FL_TRACEPOINT_BIT,
TRACE_EVENT_FL_KPROBE_BIT,
TRACE_EVENT_FL_UPROBE_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 trace 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 trace internal events, don't use file filter
* TRACEPOINT - Event is a tracepoint
* KPROBE - Event is a kprobe
* UPROBE - Event is a uprobe
*/
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),
TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT),
TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT),
TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT),
};
#define TRACE_EVENT_FL_UKPROBE (TRACE_EVENT_FL_KPROBE | TRACE_EVENT_FL_UPROBE)
struct trace_event_call {
struct list_head list;
struct trace_event_class *class;
union {
char *name;
/* Set TRACE_EVENT_FL_TRACEPOINT flag when using "tp" */
struct tracepoint *tp;
};
struct trace_event event;
char *print_fmt;
struct event_filter *filter;
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: trace internal event (do not enable)
* bit 4: Event was enabled by module
* bit 5: use call filter rather than file filter
* bit 6: Event is a tracepoint
*/
int flags; /* static flags of different events */
#ifdef CONFIG_PERF_EVENTS
int perf_refcount;
struct hlist_head __percpu *perf_events;
struct bpf_prog *prog;
int (*perf_perm)(struct trace_event_call *,
struct perf_event *);
#endif
};
static inline const char *
trace_event_name(struct trace_event_call *call)
{
if (call->flags & TRACE_EVENT_FL_TRACEPOINT)
return call->tp ? call->tp->name : NULL;
else
return call->name;
}
struct trace_array;
struct trace_subsystem_dir;
enum {
EVENT_FILE_FL_ENABLED_BIT,
EVENT_FILE_FL_RECORDED_CMD_BIT,
EVENT_FILE_FL_FILTERED_BIT,
EVENT_FILE_FL_NO_SET_FILTER_BIT,
EVENT_FILE_FL_SOFT_MODE_BIT,
EVENT_FILE_FL_SOFT_DISABLED_BIT,
EVENT_FILE_FL_TRIGGER_MODE_BIT,
EVENT_FILE_FL_TRIGGER_COND_BIT,
EVENT_FILE_FL_PID_FILTER_BIT,
};
/*
* 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
* PID_FILTER - When set, the event is filtered based on pid
*/
enum {
EVENT_FILE_FL_ENABLED = (1 << EVENT_FILE_FL_ENABLED_BIT),
EVENT_FILE_FL_RECORDED_CMD = (1 << EVENT_FILE_FL_RECORDED_CMD_BIT),
EVENT_FILE_FL_FILTERED = (1 << EVENT_FILE_FL_FILTERED_BIT),
EVENT_FILE_FL_NO_SET_FILTER = (1 << EVENT_FILE_FL_NO_SET_FILTER_BIT),
EVENT_FILE_FL_SOFT_MODE = (1 << EVENT_FILE_FL_SOFT_MODE_BIT),
EVENT_FILE_FL_SOFT_DISABLED = (1 << EVENT_FILE_FL_SOFT_DISABLED_BIT),
EVENT_FILE_FL_TRIGGER_MODE = (1 << EVENT_FILE_FL_TRIGGER_MODE_BIT),
EVENT_FILE_FL_TRIGGER_COND = (1 << EVENT_FILE_FL_TRIGGER_COND_BIT),
EVENT_FILE_FL_PID_FILTER = (1 << EVENT_FILE_FL_PID_FILTER_BIT),
};
struct trace_event_file {
struct list_head list;
struct trace_event_call *event_call;
struct event_filter *filter;
struct dentry *dir;
struct trace_array *tr;
struct trace_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 trace_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 int filter_match_preds(struct event_filter *filter, void *rec);
extern int filter_check_discard(struct trace_event_file *file, void *rec,
struct ring_buffer *buffer,
struct ring_buffer_event *event);
extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
struct ring_buffer *buffer,
struct ring_buffer_event *event);
extern enum event_trigger_type event_triggers_call(struct trace_event_file *file,
void *rec);
extern void event_triggers_post_call(struct trace_event_file *file,
enum event_trigger_type tt);
bool trace_event_ignore_this_pid(struct trace_event_file *trace_file);
/**
* trace_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
trace_trigger_soft_disabled(struct trace_event_file *file)
{
unsigned long eflags = file->flags;
if (!(eflags & EVENT_FILE_FL_TRIGGER_COND)) {
if (eflags & EVENT_FILE_FL_TRIGGER_MODE)
event_triggers_call(file, NULL);
if (eflags & EVENT_FILE_FL_SOFT_DISABLED)
return true;
if (eflags & EVENT_FILE_FL_PID_FILTER)
return trace_event_ignore_this_pid(file);
}
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 trace_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 & EVENT_FILE_FL_TRIGGER_COND)
*tt = event_triggers_call(file, entry);
if (test_bit(EVENT_FILE_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 trace_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(file->tr, 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 trace_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(file->tr, buffer, event,
irq_flags, pc, regs);
if (tt)
event_triggers_post_call(file, tt);
}
#ifdef CONFIG_BPF_EVENTS
unsigned int trace_call_bpf(struct bpf_prog *prog, void *ctx);
#else
static inline unsigned int trace_call_bpf(struct bpf_prog *prog, void *ctx)
{
return 1;
}
#endif
enum {
FILTER_OTHER = 0,
FILTER_STATIC_STRING,
FILTER_DYN_STRING,
FILTER_PTR_STRING,
FILTER_TRACE_FN,
};
extern int trace_event_raw_init(struct trace_event_call *call);
extern int trace_define_field(struct trace_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 trace_event_call *call);
extern int trace_remove_event_call(struct trace_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)
#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_TRACE_EVENT_H */