path: root/kernel/trace/trace.h

#ifndef _LINUX_KERNEL_TRACE_H
#define _LINUX_KERNEL_TRACE_H

#include <linux/fs.h>
#include <linux/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 <linux/hw_breakpoint.h>
#include <linux/trace_seq.h>
#include <linux/ftrace_event.h>

#ifdef CONFIG_FTRACE_SYSCALLS
#include <asm/unistd.h>		/* For NR_SYSCALLS	     */
#include <asm/syscall.h>	/* some archs define it here */
#endif

enum trace_type {
	__TRACE_FIRST_TYPE = 0,

	TRACE_FN,
	TRACE_CTX,
	TRACE_WAKE,
	TRACE_STACK,
	TRACE_PRINT,
	TRACE_BPRINT,
	TRACE_MMIO_RW,
	TRACE_MMIO_MAP,
	TRACE_BRANCH,
	TRACE_GRAPH_RET,
	TRACE_GRAPH_ENT,
	TRACE_USER_STACK,
	TRACE_BLK,
	TRACE_BPUTS,

	__TRACE_LAST_TYPE,
};


#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, filter)	\
	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, filter)

#undef FTRACE_ENTRY_REG
#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	\
			 filter, regfn) \
	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
		     filter)

#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_head {
	struct trace_entry	ent;
	unsigned long		ip;
};

struct kretprobe_trace_entry_head {
	struct trace_entry	ent;
	unsigned long		func;
	unsigned long		ret_ip;
};

/*
 * 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

struct trace_array;

struct trace_cpu {
	struct trace_array	*tr;
	struct dentry		*dir;
	int			cpu;
};

/*
 * 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 {
	struct trace_cpu	trace_cpu;
	atomic_t		disabled;
	void			*buffer_page;	/* ring buffer spare */

	unsigned long		entries;
	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;
	kuid_t			uid;
	char			comm[TASK_COMM_LEN];
};

struct tracer;

struct trace_buffer {
	struct trace_array		*tr;
	struct ring_buffer		*buffer;
	struct trace_array_cpu __percpu	*data;
	cycle_t				time_start;
	int				cpu;
};

/*
 * 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 list_head	list;
	char			*name;
	struct trace_buffer	trace_buffer;
#ifdef CONFIG_TRACER_MAX_TRACE
	/*
	 * The max_buffer is used to snapshot the trace when a maximum
	 * latency is reached, or when the user initiates a snapshot.
	 * Some tracers will use this to store a maximum trace while
	 * it continues examining live traces.
	 *
	 * The buffers for the max_buffer are set up the same as the trace_buffer
	 * When a snapshot is taken, the buffer of the max_buffer is swapped
	 * with the buffer of the trace_buffer and the buffers are reset for
	 * the trace_buffer so the tracing can continue.
	 */
	struct trace_buffer	max_buffer;
	bool			allocated_snapshot;
#endif
	int			buffer_disabled;
	struct trace_cpu	trace_cpu;	/* place holder */
#ifdef CONFIG_FTRACE_SYSCALLS
	int			sys_refcount_enter;
	int			sys_refcount_exit;
	DECLARE_BITMAP(enabled_enter_syscalls, NR_syscalls);
	DECLARE_BITMAP(enabled_exit_syscalls, NR_syscalls);
#endif
	int			stop_count;
	int			clock_id;
	struct tracer		*current_trace;
	unsigned int		flags;
	raw_spinlock_t		start_lock;
	struct dentry		*dir;
	struct dentry		*options;
	struct dentry		*percpu_dir;
	struct dentry		*event_dir;
	struct list_head	systems;
	struct list_head	events;
	struct task_struct	*waiter;
	int			ref;