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#ifndef _LINUX_KERNEL_TRACE_H
#define _LINUX_KERNEL_TRACE_H
#include <linux/fs.h>
#include <asm/atomic.h>
#include <linux/sched.h>
#include <linux/clocksource.h>
#include <linux/ring_buffer.h>
#include <linux/mmiotrace.h>
#include <linux/tracepoint.h>
#include <linux/ftrace.h>
#include <trace/boot.h>
#include <linux/kmemtrace.h>
#include <linux/hw_breakpoint.h>
#include <linux/trace_seq.h>
#include <linux/ftrace_event.h>
enum trace_type {
__TRACE_FIRST_TYPE = 0,
TRACE_FN,
TRACE_CTX,
TRACE_WAKE,
TRACE_STACK,
TRACE_PRINT,
TRACE_BPRINT,
TRACE_SPECIAL,
TRACE_MMIO_RW,
TRACE_MMIO_MAP,
TRACE_BRANCH,
TRACE_BOOT_CALL,
TRACE_BOOT_RET,
TRACE_GRAPH_RET,
TRACE_GRAPH_ENT,
TRACE_USER_STACK,
TRACE_HW_BRANCHES,
TRACE_KMEM_ALLOC,
TRACE_KMEM_FREE,
TRACE_BLK,
TRACE_KSYM,
__TRACE_LAST_TYPE,
};
enum kmemtrace_type_id {
KMEMTRACE_TYPE_KMALLOC = 0, /* kmalloc() or kfree(). */
KMEMTRACE_TYPE_CACHE, /* kmem_cache_*(). */
KMEMTRACE_TYPE_PAGES, /* __get_free_pages() and friends. */
};
extern struct tracer boot_tracer;
#undef __field
#define __field(type, item) type item;
#undef __field_struct
#define __field_struct(type, item) __field(type, item)
#undef __field_desc
#define __field_desc(type, container, item)
#undef __array
#define __array(type, item, size) type item[size];
#undef __array_desc
#define __array_desc(type, container, item, size)
#undef __dynamic_array
#define __dynamic_array(type, item) type item[];
#undef F_STRUCT
#define F_STRUCT(args...) args
#undef FTRACE_ENTRY
#define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \
struct struct_name { \
struct trace_entry ent; \
tstruct \
}
#undef TP_ARGS
#define TP_ARGS(args...) args
#undef FTRACE_ENTRY_DUP
#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)
#include "trace_entries.h"
/*
* syscalls are special, and need special handling, this is why
* they are not included in trace_entries.h
*/
struct syscall_trace_enter {
struct trace_entry ent;
int nr;
unsigned long args[];
};
struct syscall_trace_exit {
struct trace_entry ent;
int nr;
long ret;
};
struct kprobe_trace_entry {
struct trace_entry ent;
unsigned long ip;
int nargs;
unsigned long args[];
};
#define SIZEOF_KPROBE_TRACE_ENTRY(n) \
(offsetof(struct kprobe_trace_entry, args) + \
(sizeof(unsigned long) * (n)))
struct kretprobe_trace_entry {
struct trace_entry ent;
unsigned long func;
unsigned long ret_ip;
int nargs;
unsigned long args[];
};
#define SIZEOF_KRETPROBE_TRACE_ENTRY(n) \
(offsetof(struct kretprobe_trace_entry, args) + \
(sizeof(unsigned long) * (n)))
/*
* trace_flag_type is an enumeration that holds different
* states when a trace occurs. These are:
* IRQS_OFF - interrupts were disabled
* IRQS_NOSUPPORT - arch does not support irqs_disabled_flags
* NEED_RESCHED - reschedule is requested
* HARDIRQ - inside an interrupt handler
* SOFTIRQ - inside a softirq handler
*/
enum trace_flag_type {
TRACE_FLAG_IRQS_OFF = 0x01,
TRACE_FLAG_IRQS_NOSUPPORT = 0x02,
TRACE_FLAG_NEED_RESCHED = 0x04,
TRACE_FLAG_HARDIRQ = 0x08,
TRACE_FLAG_SOFTIRQ = 0x10,
};
#define TRACE_BUF_SIZE 1024
/*
* The CPU trace array - it consists of thousands of trace entries
* plus some other descriptor data: (for example which task started
* the trace, etc.)
*/
struct trace_array_cpu {
atomic_t disabled;
void *buffer_page; /* ring buffer spare */
unsigned long saved_latency;
unsigned long critical_start;
unsigned long critical_end;
unsigned long critical_sequence;
unsigned long nice;
unsigned long policy;
unsigned long rt_priority;
unsigned long skipped_entries;
cycle_t preempt_timestamp;
pid_t pid;
uid_t uid;
char comm[TASK_COMM_LEN];
};
/*
* The trace array - an array of per-CPU trace arrays. This is the
* highest level data structure that individual tracers deal with.
* They have on/off state as well:
*/
struct trace_array {
struct ring_buffer *buffer;
unsigned long entries;
int cpu;
cycle_t time_start;
struct task_struct *waiter;
struct trace_array_cpu *data[NR_CPUS];
};
#define FTRACE_CMP_TYPE(var, type) \
__builtin_types_compatible_p(typeof(var), type *)
#undef IF_ASSIGN
#define IF_ASSIGN(var, entry, etype, id) \
if (FTRACE_CMP_TYPE(var, etype)) { \
var = (typeof(var))(entry); \
WARN_ON(id && (entry)->type != id); \
break; \
}
/* Will cause compile errors if type is not found. */
extern void __ftrace_bad_type(void);
/*
* The trace_assign_type is a verifier that the entry type is
* the same as the type being assigned. To add new types simply
* add a line with the following format:
*
* IF_ASSIGN(var, ent, type, id);
*
* Where "type" is the trace type that includes the trace_entry
* as the "ent" item. And "id" is the trace identifier that is
* used in the trace_type enum.
*
* If the type can have more than one id, then use zero.
*/
#define trace_assign_type(var, ent) \
do { \
IF_ASSIGN(var, ent, struct ftrace_entry, TRACE_FN); \
IF_ASSIGN(var, ent, struct ctx_switch_entry, 0); \
IF_ASSIGN(var, ent, struct stack_entry, TRACE_STACK); \
IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT); \
IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT); \
IF_ASSIGN(var, ent, struct special_entry, 0); \
IF_ASSIGN(var, ent, struct trace_mmiotrace_rw, \
TRACE_MMIO_RW); \
IF_ASSIGN(var, ent, struct trace_mmiotrace_map, \
TRACE_MMIO_MAP); \
IF_ASSIGN(var, ent, struct trace_boot_call, TRACE_BOOT_CALL);\
IF_ASSIGN(var, ent, struct trace_boot_ret, TRACE_BOOT_RET);\
IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry, \
TRACE_GRAPH_ENT); \
IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry, \
TRACE_GRAPH_RET); \
IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry, \
TRACE_KMEM_ALLOC); \
IF_ASSIGN(var, ent, struct kmemtrace_free_entry, \
TRACE_KMEM_FREE); \
IF_ASSIGN(var, ent, struct ksym_trace_entry, TRACE_KSYM);\
__ftrace_bad_type(); \
} while (0)
/*
* An option specific to a tracer. This is a boolean value.
* The bit is the bit index that sets its value on the
* flags value in struct tracer_flags.
*/
struct tracer_opt {
const char *name; /* Will appear on the trace_options file */
u32 bit; /* Mask assigned in val field in tracer_flags */
};
/*
* The set of specific options for a tracer. Your tracer
* have to set the initial value of the flags val.
*/
struct tracer_flags {
u32 val;
struct tracer_opt *opts;
};
/* Makes more easy to define a tracer opt */
#define TRACER_OPT(s, b) .name = #s, .bit = b
/**
* struct tracer - a specific tracer and its callbacks to interact with debugfs
* @name: the name chosen to select it on the available_tracers file
* @init: called when one switches to this tracer (echo name > current_tracer)
* @reset: called when one switches to another tracer
* @start: called when tracing is unpaused (echo 1 > tracing_enabled)
* @stop: called when tracing is paused (echo 0 > tracing_enabled)
* @open: called when the trace file is opened
* @pipe_open: called when the trace_pipe file is opened
* @wait_pipe: override how the user waits for traces on trace_pipe
* @close: called when the trace file is released
* @pipe_close: called when the trace_pipe file is released
* @read: override the default read callback on trace_pipe
* @splice_read: override the default splice_read callback on trace_pipe
* @selftest: selftest to run on boot (see trace_selftest.c)
* @print_headers: override the first lines that describe your columns
* @print_line: callback that prints a trace
* @set_flag: signals one of your private flags changed (trace_options file)
* @flags: your private flags
*/
struct tracer {
const char *name;
int (*init)(struct trace_array *tr);
void (*reset)(struct trace_array *tr);
void (*start)(struct trace_array *tr);
void (*stop)(struct trace_array *tr);
void (*open)(struct trace_iterator *iter);
void (*pipe_open)(struct trace_iterator *iter);
void (*wait_pipe)(struct trace_iterator *iter);
void (*close)(struct trace_iterator *iter);
void (*pipe_close)(struct trace_iterator *iter);
ssize_t (*read)(struct trace_iterator *iter,
struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos);
ssize_t (*splice_read)(struct trace_iterator *iter,
struct file *filp,
loff_t *ppos,
struct pipe_inode_info *pipe,
size_t len,
unsigned int flags);
#ifdef CONFIG_FTRACE_STARTUP_TEST
int (*selftest)(struct tracer *trace,
struct trace_array *tr);
#endif
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