// SPDX-License-Identifier: GPL-2.0

  #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/trace.h>

  #include <linux/hw_breakpoint.h>

  #include <linux/trace_seq.h>

  #include <linux/trace_events.h>

  #include <linux/compiler.h>

  #include <linux/glob.h>

  #include <linux/irq_work.h>
  #include <linux/workqueue.h>

  #include <linux/ctype.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_HWLAT,

  	TRACE_RAW_DATA,

  	__TRACE_LAST_TYPE,

  };

  #undef __field
  #define __field(type, item)		type	item;

  #undef __field_fn
  #define __field_fn(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 __field_packed
  #define __field_packed(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 FTRACE_ENTRY_DUP

  #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk)

  #undef FTRACE_ENTRY_REG

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

  #undef FTRACE_ENTRY_PACKED

  #define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print)	\
  	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print)) __packed

  #include "trace_entries.h"

  /* Use this for memory failure errors */
  #define MEM_FAIL(condition, fmt, ...) ({			\

  	static bool __section(".data.once") __warned;		\

  	int __ret_warn_once = !!(condition);			\
  								\
  	if (unlikely(__ret_warn_once && !__warned)) {		\
  		__warned = true;				\
  		pr_err("ERROR: " fmt, ##__VA_ARGS__);		\
  	}							\
  	unlikely(__ret_warn_once);				\
  })

  /*
   * 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,

  	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,

  	TRACE_FLAG_NMI			= 0x40,

  };

  #define TRACE_BUF_SIZE		1024

  struct trace_array;

  /*
   * 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		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;

  	u64			preempt_timestamp;

  	pid_t			pid;

  	kuid_t			uid;

  	char			comm[TASK_COMM_LEN];

  #ifdef CONFIG_FUNCTION_TRACER

  	int			ftrace_ignore_pid;

  #endif

  	bool			ignore_pid;

  };

  struct tracer;

  struct trace_option_dentry;

  struct array_buffer {

  	struct trace_array		*tr;

  	struct trace_buffer		*buffer;

  	struct trace_array_cpu __percpu	*data;

  	u64				time_start;

  	int				cpu;
  };

  #define TRACE_FLAGS_MAX_SIZE		32

  struct trace_options {
  	struct tracer			*tracer;
  	struct trace_option_dentry	*topts;
  };

  struct trace_pid_list {

  	int				pid_max;
  	unsigned long			*pids;

  };

  enum {
  	TRACE_PIDS		= BIT(0),
  	TRACE_NO_PIDS		= BIT(1),
  };
  
  static inline bool pid_type_enabled(int type, struct trace_pid_list *pid_list,
  				    struct trace_pid_list *no_pid_list)
  {
  	/* Return true if the pid list in type has pids */
  	return ((type & TRACE_PIDS) && pid_list) ||
  		((type & TRACE_NO_PIDS) && no_pid_list);
  }
  
  static inline bool still_need_pid_events(int type, struct trace_pid_list *pid_list,
  					 struct trace_pid_list *no_pid_list)
  {
  	/*
  	 * Turning off what is in @type, return true if the "other"
  	 * pid list, still has pids in it.
  	 */
  	return (!(type & TRACE_PIDS) && pid_list) ||
  		(!(type & TRACE_NO_PIDS) && no_pid_list);
  }

  typedef bool (*cond_update_fn_t)(struct trace_array *tr, void *cond_data);
  
  /**
   * struct cond_snapshot - conditional snapshot data and callback
   *
   * The cond_snapshot structure encapsulates a callback function and
   * data associated with the snapshot for a given tracing instance.
   *
   * When a snapshot is taken conditionally, by invoking
   * tracing_snapshot_cond(tr, cond_data), the cond_data passed in is
   * passed in turn to the cond_snapshot.update() function.  That data
   * can be compared by the update() implementation with the cond_data

   * contained within the struct cond_snapshot instance associated with

   * the trace_array.  Because the tr->max_lock is held throughout the
   * update() call, the update() function can directly retrieve the
   * cond_snapshot and cond_data associated with the per-instance
   * snapshot associated with the trace_array.
   *
   * The cond_snapshot.update() implementation can save data to be
   * associated with the snapshot if it decides to, and returns 'true'
   * in that case, or it returns 'false' if the conditional snapshot
   * shouldn't be taken.
   *
   * The cond_snapshot instance is created and associated with the
   * user-defined cond_data by tracing_cond_snapshot_enable().
   * Likewise, the cond_snapshot instance is destroyed and is no longer
   * associated with the trace instance by
   * tracing_cond_snapshot_disable().
   *
   * The method below is required.
   *
   * @update: When a conditional snapshot is invoked, the update()
   *	callback function is invoked with the tr->max_lock held.  The
   *	update() implementation signals whether or not to actually
   *	take the snapshot, by returning 'true' if so, 'false' if no
   *	snapshot should be taken.  Because the max_lock is held for
   *	the duration of update(), the implementation is safe to

   *	directly retrieved and save any implementation data it needs

   *	to in association with the snapshot.
   */
  struct cond_snapshot {
  	void				*cond_data;
  	cond_update_fn_t		update;
  };

  /*
   * 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 array_buffer	array_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 array_buffer

  	 * When a snapshot is taken, the buffer of the max_buffer is swapped

  	 * with the buffer of the array_buffer and the buffers are reset for
  	 * the array_buffer so the tracing can continue.

  	 */

  	struct array_buffer	max_buffer;

  	bool			allocated_snapshot;

  #endif
  #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)

  	unsigned long		max_latency;

  #ifdef CONFIG_FSNOTIFY
  	struct dentry		*d_max_latency;
  	struct work_struct	fsnotify_work;
  	struct irq_work		fsnotify_irqwork;
  #endif

  #endif

  	struct trace_pid_list	__rcu *filtered_pids;

  	struct trace_pid_list	__rcu *filtered_no_pids;

  	/*
  	 * max_lock is used to protect the swapping of buffers
  	 * when taking a max snapshot. The buffers themselves are
  	 * protected by per_cpu spinlocks. But the action of the swap
  	 * needs its own lock.
  	 *
  	 * This is defined as a arch_spinlock_t in order to help
  	 * with performance when lockdep debugging is enabled.
  	 *
  	 * It is also used in other places outside the update_max_tr
  	 * so it needs to be defined outside of the
  	 * CONFIG_TRACER_MAX_TRACE.
  	 */
  	arch_spinlock_t		max_lock;

  	int			buffer_disabled;

  #ifdef CONFIG_FTRACE_SYSCALLS
  	int			sys_refcount_enter;
  	int			sys_refcount_exit;

  	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
  	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];

  #endif

  	int			stop_count;
  	int			clock_id;

  	int			nr_topts;

  	bool			clear_trace;

  	int			buffer_percent;

  	unsigned int		n_err_log_entries;

  	struct tracer		*current_trace;

  	unsigned int		trace_flags;

  	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];

  	unsigned int		flags;

  	raw_spinlock_t		start_lock;

  	struct list_head	err_log;

  	struct dentry		*dir;

  	struct dentry		*options;
  	struct dentry		*percpu_dir;

  	struct dentry		*event_dir;

  	struct trace_options	*topts;

  	struct list_head	systems;
  	struct list_head	events;

  	struct trace_event_file *trace_marker_file;

  	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */

  	int			ref;

  	int			trace_ref;

  #ifdef CONFIG_FUNCTION_TRACER
  	struct ftrace_ops	*ops;

  	struct trace_pid_list	__rcu *function_pids;

  	struct trace_pid_list	__rcu *function_no_pids;

  #ifdef CONFIG_DYNAMIC_FTRACE

  	/* All of these are protected by the ftrace_lock */

  	struct list_head	func_probes;

  	struct list_head	mod_trace;
  	struct list_head	mod_notrace;

  #endif

  	/* function tracing enabled */
  	int			function_enabled;
  #endif

  	int			time_stamp_abs_ref;

  	struct list_head	hist_vars;

  #ifdef CONFIG_TRACER_SNAPSHOT
  	struct cond_snapshot	*cond_snapshot;
  #endif

  };

  enum {
  	TRACE_ARRAY_FL_GLOBAL	= (1 << 0)
  };
  
  extern struct list_head ftrace_trace_arrays;

  extern struct mutex trace_types_lock;

  extern int trace_array_get(struct trace_array *tr);

  extern int tracing_check_open_get_tr(struct trace_array *tr);

  extern struct trace_array *trace_array_find(const char *instance);
  extern struct trace_array *trace_array_find_get(const char *instance);

  extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs);

  extern int tracing_set_clock(struct trace_array *tr, const char *clockstr);

  extern bool trace_clock_in_ns(struct trace_array *tr);

  /*
   * The global tracer (top) should be the first trace array added,
   * but we check the flag anyway.
   */
  static inline struct trace_array *top_trace_array(void)
  {
  	struct trace_array *tr;

  	if (list_empty(&ftrace_trace_arrays))

  		return NULL;

  	tr = list_entry(ftrace_trace_arrays.prev,
  			typeof(*tr), list);
  	WARN_ON(!(tr->flags & TRACE_ARRAY_FL_GLOBAL));
  	return tr;
  }

  #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 != 0 && (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 bputs_entry, TRACE_BPUTS);	\

  		IF_ASSIGN(var, ent, struct hwlat_entry, TRACE_HWLAT);	\

  		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\

  		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_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);		\

  		__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;

  	struct tracer		*trace;

  };
  
  /* Makes more easy to define a tracer opt */
  #define TRACER_OPT(s, b)	.name = #s, .bit = b

  struct trace_option_dentry {
  	struct tracer_opt		*opt;
  	struct tracer_flags		*flags;
  	struct trace_array		*tr;
  	struct dentry			*entry;
  };

  /**

   * struct tracer - a specific tracer and its callbacks to interact with tracefs

   * @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_on)
   * @stop: called when tracing is paused (echo 0 > tracing_on)

   * @update_thresh: called when tracing_thresh is updated

   * @open: called when the trace file is opened
   * @pipe_open: called when the trace_pipe file is opened

   * @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);

  	int			(*update_thresh)(struct trace_array *tr);

  	void			(*open)(struct trace_iterator *iter);

  	void			(*pipe_open)(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

  	void			(*print_header)(struct seq_file *m);

  	enum print_line_t	(*print_line)(struct trace_iterator *iter);

  	/* If you handled the flag setting, return 0 */

  	int			(*set_flag)(struct trace_array *tr,
  					    u32 old_flags, u32 bit, int set);

  	/* Return 0 if OK with change, else return non-zero */

  	int			(*flag_changed)(struct trace_array *tr,

  						u32 mask, int set);

  	struct tracer		*next;

  	struct tracer_flags	*flags;

  	int			enabled;

  	bool			print_max;

  	bool			allow_instances;

  #ifdef CONFIG_TRACER_MAX_TRACE

  	bool			use_max_tr;

  #endif

  	/* True if tracer cannot be enabled in kernel param */
  	bool			noboot;

  };

  /* Only current can touch trace_recursion */

  /*
   * For function tracing recursion:
   *  The order of these bits are important.
   *
   *  When function tracing occurs, the following steps are made:
   *   If arch does not support a ftrace feature:
   *    call internal function (uses INTERNAL bits) which calls...
   *   If callback is registered to the "global" list, the list
   *    function is called and recursion checks the GLOBAL bits.
   *    then this function calls...
   *   The function callback, which can use the FTRACE bits to
   *    check for recursion.
   *

   * Now if the arch does not support a feature, and it calls

   * the global list function which calls the ftrace callback
   * all three of these steps will do a recursion protection.
   * There's no reason to do one if the previous caller already
   * did. The recursion that we are protecting against will
   * go through the same steps again.
   *
   * To prevent the multiple recursion checks, if a recursion
   * bit is set that is higher than the MAX bit of the current
   * check, then we know that the check was made by the previous
   * caller, and we can skip the current check.
   */

  enum {

  	/* Function recursion bits */

  	TRACE_FTRACE_BIT,

  	TRACE_FTRACE_NMI_BIT,
  	TRACE_FTRACE_IRQ_BIT,
  	TRACE_FTRACE_SIRQ_BIT,

  	/* INTERNAL_BITs must be greater than FTRACE_BITs */

  	TRACE_INTERNAL_BIT,
  	TRACE_INTERNAL_NMI_BIT,
  	TRACE_INTERNAL_IRQ_BIT,
  	TRACE_INTERNAL_SIRQ_BIT,

  	TRACE_BRANCH_BIT,

  /*
   * Abuse of the trace_recursion.
   * As we need a way to maintain state if we are tracing the function
   * graph in irq because we want to trace a particular function that
   * was called in irq context but we have irq tracing off. Since this
   * can only be modified by current, we can reuse trace_recursion.
   */

  	TRACE_IRQ_BIT,

  
  	/* Set if the function is in the set_graph_function file */
  	TRACE_GRAPH_BIT,
  
  	/*
  	 * In the very unlikely case that an interrupt came in
  	 * at a start of graph tracing, and we want to trace
  	 * the function in that interrupt, the depth can be greater
  	 * than zero, because of the preempted start of a previous
  	 * trace. In an even more unlikely case, depth could be 2
  	 * if a softirq interrupted the start of graph tracing,
  	 * followed by an interrupt preempting a start of graph
  	 * tracing in the softirq, and depth can even be 3
  	 * if an NMI came in at the start of an interrupt function
  	 * that preempted a softirq start of a function that
  	 * preempted normal context!!!! Luckily, it can't be
  	 * greater than 3, so the next two bits are a mask
  	 * of what the depth is when we set TRACE_GRAPH_BIT
  	 */
  
  	TRACE_GRAPH_DEPTH_START_BIT,
  	TRACE_GRAPH_DEPTH_END_BIT,

  
  	/*
  	 * To implement set_graph_notrace, if this bit is set, we ignore
  	 * function graph tracing of called functions, until the return
  	 * function is called to clear it.
  	 */
  	TRACE_GRAPH_NOTRACE_BIT,

  
  	/*
  	 * When transitioning between context, the preempt_count() may
  	 * not be correct. Allow for a single recursion to cover this case.
  	 */
  	TRACE_TRANSITION_BIT,

  };

  #define trace_recursion_set(bit)	do { (current)->trace_recursion |= (1<<(bit)); } while (0)
  #define trace_recursion_clear(bit)	do { (current)->trace_recursion &= ~(1<<(bit)); } while (0)
  #define trace_recursion_test(bit)	((current)->trace_recursion & (1<<(bit)))

  #define trace_recursion_depth() \
  	(((current)->trace_recursion >> TRACE_GRAPH_DEPTH_START_BIT) & 3)
  #define trace_recursion_set_depth(depth) \
  	do {								\
  		current->trace_recursion &=				\
  			~(3 << TRACE_GRAPH_DEPTH_START_BIT);		\
  		current->trace_recursion |=				\
  			((depth) & 3) << TRACE_GRAPH_DEPTH_START_BIT;	\
  	} while (0)

  #define TRACE_CONTEXT_BITS	4
  
  #define TRACE_FTRACE_START	TRACE_FTRACE_BIT
  #define TRACE_FTRACE_MAX	((1 << (TRACE_FTRACE_START + TRACE_CONTEXT_BITS)) - 1)

  #define TRACE_LIST_START	TRACE_INTERNAL_BIT
  #define TRACE_LIST_MAX		((1 << (TRACE_LIST_START + TRACE_CONTEXT_BITS)) - 1)
  
  #define TRACE_CONTEXT_MASK	TRACE_LIST_MAX
  
  static __always_inline int trace_get_context_bit(void)
  {
  	int bit;
  
  	if (in_interrupt()) {
  		if (in_nmi())
  			bit = 0;
  
  		else if (in_irq())
  			bit = 1;
  		else
  			bit = 2;
  	} else
  		bit = 3;
  
  	return bit;
  }
  
  static __always_inline int trace_test_and_set_recursion(int start, int max)
  {
  	unsigned int val = current->trace_recursion;
  	int bit;
  
  	/* A previous recursion check was made */
  	if ((val & TRACE_CONTEXT_MASK) > max)
  		return 0;
  
  	bit = trace_get_context_bit() + start;

  	if (unlikely(val & (1 << bit))) {
  		/*
  		 * It could be that preempt_count has not been updated during
  		 * a switch between contexts. Allow for a single recursion.
  		 */
  		bit = TRACE_TRANSITION_BIT;
  		if (trace_recursion_test(bit))
  			return -1;
  		trace_recursion_set(bit);
  		barrier();
  		return bit + 1;
  	}
  
  	/* Normal check passed, clear the transition to allow it again */
  	trace_recursion_clear(TRACE_TRANSITION_BIT);

  
  	val |= 1 << bit;
  	current->trace_recursion = val;
  	barrier();

  	return bit + 1;

  }
  
  static __always_inline void trace_clear_recursion(int bit)
  {
  	unsigned int val = current->trace_recursion;
  
  	if (!bit)
  		return;

  	bit--;

  	bit = 1 << bit;
  	val &= ~bit;
  
  	barrier();
  	current->trace_recursion = val;
  }

  static inline struct ring_buffer_iter *
  trace_buffer_iter(struct trace_iterator *iter, int cpu)
  {

  	return iter->buffer_iter ? iter->buffer_iter[cpu] : NULL;

  }

  int tracer_init(struct tracer *t, struct trace_array *tr);

  int tracing_is_enabled(void);

  void tracing_reset_online_cpus(struct array_buffer *buf);

  void tracing_reset_current(int cpu);

  void tracing_reset_all_online_cpus(void);

  int tracing_open_generic(struct inode *inode, struct file *filp);

  int tracing_open_generic_tr(struct inode *inode, struct file *filp);

  bool tracing_is_disabled(void);

  bool tracer_tracing_is_on(struct trace_array *tr);

  void tracer_tracing_on(struct trace_array *tr);
  void tracer_tracing_off(struct trace_array *tr);

  struct dentry *trace_create_file(const char *name,

  				 umode_t mode,

  				 struct dentry *parent,
  				 void *data,
  				 const struct file_operations *fops);

  int tracing_init_dentry(void);

  struct ring_buffer_event;

  struct ring_buffer_event *

  trace_buffer_lock_reserve(struct trace_buffer *buffer,

  			  int type,
  			  unsigned long len,
  			  unsigned long flags,
  			  int pc);

  struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
  						struct trace_array_cpu *data);

  
  struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
  					  int *ent_cpu, u64 *ent_ts);

  void trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer,

  					struct ring_buffer_event *event);

  int trace_empty(struct trace_iterator *iter);
  
  void *trace_find_next_entry_inc(struct trace_iterator *iter);
  
  void trace_init_global_iter(struct trace_iterator *iter);
  
  void tracing_iter_reset(struct trace_iterator *iter, int cpu);

  unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu);
  unsigned long trace_total_entries(struct trace_array *tr);

  void trace_function(struct trace_array *tr,

  		    unsigned long ip,
  		    unsigned long parent_ip,

  		    unsigned long flags, int pc);

  void trace_graph_function(struct trace_array *tr,
  		    unsigned long ip,
  		    unsigned long parent_ip,
  		    unsigned long flags, int pc);

  void trace_latency_header(struct seq_file *m);

  void trace_default_header(struct seq_file *m);
  void print_trace_header(struct seq_file *m, struct trace_iterator *iter);
  int trace_empty(struct trace_iterator *iter);

  void trace_graph_return(struct ftrace_graph_ret *trace);

  int trace_graph_entry(struct ftrace_graph_ent *trace);

  void set_graph_array(struct trace_array *tr);

  void tracing_start_cmdline_record(void);
  void tracing_stop_cmdline_record(void);

  void tracing_start_tgid_record(void);
  void tracing_stop_tgid_record(void);

  int register_tracer(struct tracer *type);

  int is_tracing_stopped(void);

  loff_t tracing_lseek(struct file *file, loff_t offset, int whence);

  extern cpumask_var_t __read_mostly tracing_buffer_mask;
  
  #define for_each_tracing_cpu(cpu)	\
  	for_each_cpu(cpu, tracing_buffer_mask)

  
  extern unsigned long nsecs_to_usecs(unsigned long nsecs);

  extern unsigned long tracing_thresh;

  /* PID filtering */

  
  extern int pid_max;

  bool trace_find_filtered_pid(struct trace_pid_list *filtered_pids,
  			     pid_t search_pid);
  bool trace_ignore_this_task(struct trace_pid_list *filtered_pids,

  			    struct trace_pid_list *filtered_no_pids,

  			    struct task_struct *task);
  void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
  				  struct task_struct *self,
  				  struct task_struct *task);

  void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos);
  void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos);
  int trace_pid_show(struct seq_file *m, void *v);

  void trace_free_pid_list(struct trace_pid_list *pid_list);
  int trace_pid_write(struct trace_pid_list *filtered_pids,
  		    struct trace_pid_list **new_pid_list,
  		    const char __user *ubuf, size_t cnt);

  #ifdef CONFIG_TRACER_MAX_TRACE

  void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu,
  		   void *cond_data);

  void update_max_tr_single(struct trace_array *tr,
  			  struct task_struct *tsk, int cpu);

  #endif /* CONFIG_TRACER_MAX_TRACE */

  #if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)) && \
  	defined(CONFIG_FSNOTIFY)
  
  void latency_fsnotify(struct trace_array *tr);
  
  #else

  static inline void latency_fsnotify(struct trace_array *tr) { }

  
  #endif

  #ifdef CONFIG_STACKTRACE

  void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
  		   int pc);
  #else

  static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
  				 int skip, int pc)
  {
  }
  #endif /* CONFIG_STACKTRACE */

  extern u64 ftrace_now(int cpu);

  extern void trace_find_cmdline(int pid, char comm[]);

  extern int trace_find_tgid(int pid);

  extern void trace_event_follow_fork(struct trace_array *tr, bool enable);

  #ifdef CONFIG_DYNAMIC_FTRACE
  extern unsigned long ftrace_update_tot_cnt;

  extern unsigned long ftrace_number_of_pages;
  extern unsigned long ftrace_number_of_groups;

  void ftrace_init_trace_array(struct trace_array *tr);
  #else
  static inline void ftrace_init_trace_array(struct trace_array *tr) { }

  #endif

  #define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
  extern int DYN_FTRACE_TEST_NAME(void);

  #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
  extern int DYN_FTRACE_TEST_NAME2(void);

  extern bool ring_buffer_expanded;

  extern bool tracing_selftest_disabled;

  #ifdef CONFIG_FTRACE_STARTUP_TEST

  extern void __init disable_tracing_selftest(const char *reason);

  extern int trace_selftest_startup_function(struct tracer *trace,
  					   struct trace_array *tr);

  extern int trace_selftest_startup_function_graph(struct tracer *trace,
  						 struct trace_array *tr);

  extern int trace_selftest_startup_irqsoff(struct tracer *trace,
  					  struct trace_array *tr);

  extern int trace_selftest_startup_preemptoff(struct tracer *trace,
  					     struct trace_array *tr);

  extern int trace_selftest_startup_preemptirqsoff(struct tracer *trace,
  						 struct trace_array *tr);

  extern int trace_selftest_startup_wakeup(struct tracer *trace,
  					 struct trace_array *tr);

  extern int trace_selftest_startup_nop(struct tracer *trace,
  					 struct trace_array *tr);

  extern int trace_selftest_startup_branch(struct tracer *trace,
  					 struct trace_array *tr);

  /*
   * Tracer data references selftest functions that only occur
   * on boot up. These can be __init functions. Thus, when selftests
   * are enabled, then the tracers need to reference __init functions.
   */
  #define __tracer_data		__refdata
  #else

  static inline void __init disable_tracing_selftest(const char *reason)
  {
  }

  /* Tracers are seldom changed. Optimize when selftests are disabled. */
  #define __tracer_data		__read_mostly

  #endif /* CONFIG_FTRACE_STARTUP_TEST */

  extern void *head_page(struct trace_array_cpu *data);

  extern unsigned long long ns2usecs(u64 nsec);

  extern int

  trace_vbprintk(unsigned long ip, const char *fmt, va_list args);

  extern int

  trace_vprintk(unsigned long ip, const char *fmt, va_list args);

  extern int
  trace_array_vprintk(struct trace_array *tr,
  		    unsigned long ip, const char *fmt, va_list args);

  int trace_array_printk_buf(struct trace_buffer *buffer,

  			   unsigned long ip, const char *fmt, ...);

  void trace_printk_seq(struct trace_seq *s);
  enum print_line_t print_trace_line(struct trace_iterator *iter);

  extern char trace_find_mark(unsigned long long duration);

  struct ftrace_hash;
  
  struct ftrace_mod_load {
  	struct list_head	list;
  	char			*func;
  	char			*module;
  	int			 enable;
  };

  enum {
  	FTRACE_HASH_FL_MOD	= (1 << 0),
  };

  struct ftrace_hash {
  	unsigned long		size_bits;
  	struct hlist_head	*buckets;
  	unsigned long		count;

  	unsigned long		flags;

  	struct rcu_head		rcu;
  };
  
  struct ftrace_func_entry *
  ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip);

  static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)

  {

  	return !hash || !(hash->count || (hash->flags & FTRACE_HASH_FL_MOD));

  }

  /* Standard output formatting function used for function return traces */

  #ifdef CONFIG_FUNCTION_GRAPH_TRACER

  
  /* Flag options */
  #define TRACE_GRAPH_PRINT_OVERRUN       0x1
  #define TRACE_GRAPH_PRINT_CPU           0x2
  #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
  #define TRACE_GRAPH_PRINT_PROC          0x8
  #define TRACE_GRAPH_PRINT_DURATION      0x10
  #define TRACE_GRAPH_PRINT_ABS_TIME      0x20

  #define TRACE_GRAPH_PRINT_REL_TIME      0x40
  #define TRACE_GRAPH_PRINT_IRQS          0x80
  #define TRACE_GRAPH_PRINT_TAIL          0x100
  #define TRACE_GRAPH_SLEEP_TIME          0x200
  #define TRACE_GRAPH_GRAPH_TIME          0x400

  #define TRACE_GRAPH_PRINT_FILL_SHIFT	28
  #define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)

  extern void ftrace_graph_sleep_time_control(bool enable);

  
  #ifdef CONFIG_FUNCTION_PROFILER

  extern void ftrace_graph_graph_time_control(bool enable);

  #else
  static inline void ftrace_graph_graph_time_control(bool enable) { }
  #endif

  extern enum print_line_t
  print_graph_function_flags(struct trace_iterator *iter, u32 flags);
  extern void print_graph_headers_flags(struct seq_file *s, u32 flags);

  extern void

  trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);

  extern void graph_trace_open(struct trace_iterator *iter);
  extern void graph_trace_close(struct trace_iterator *iter);
  extern int __trace_graph_entry(struct trace_array *tr,
  			       struct ftrace_graph_ent *trace,
  			       unsigned long flags, int pc);
  extern void __trace_graph_return(struct trace_array *tr,
  				 struct ftrace_graph_ret *trace,
  				 unsigned long flags, int pc);

  #ifdef CONFIG_DYNAMIC_FTRACE

  extern struct ftrace_hash __rcu *ftrace_graph_hash;

  extern struct ftrace_hash __rcu *ftrace_graph_notrace_hash;

  static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)

  {

  	unsigned long addr = trace->func;

  	int ret = 0;

  	struct ftrace_hash *hash;

  
  	preempt_disable_notrace();

  	/*
  	 * Have to open code "rcu_dereference_sched()" because the
  	 * function graph tracer can be called when RCU is not
  	 * "watching".

  	 * Protected with schedule_on_each_cpu(ftrace_sync)

  	 */

  	hash = rcu_dereference_protected(ftrace_graph_hash, !preemptible());
  
  	if (ftrace_hash_empty(hash)) {

  		ret = 1;
  		goto out;

  	}

  	if (ftrace_lookup_ip(hash, addr)) {

  
  		/*
  		 * This needs to be cleared on the return functions
  		 * when the depth is zero.
  		 */
  		trace_recursion_set(TRACE_GRAPH_BIT);
  		trace_recursion_set_depth(trace->depth);

  		/*
  		 * If no irqs are to be traced, but a set_graph_function
  		 * is set, and called by an interrupt handler, we still
  		 * want to trace it.
  		 */
  		if (in_irq())
  			trace_recursion_set(TRACE_IRQ_BIT);
  		else
  			trace_recursion_clear(TRACE_IRQ_BIT);
  		ret = 1;
  	}
  
  out:
  	preempt_enable_notrace();
  	return ret;

  }

  static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
  {
  	if (trace_recursion_test(TRACE_GRAPH_BIT) &&
  	    trace->depth == trace_recursion_depth())
  		trace_recursion_clear(TRACE_GRAPH_BIT);
  }

  static inline int ftrace_graph_notrace_addr(unsigned long addr)
  {

  	int ret = 0;

  	struct ftrace_hash *notrace_hash;

  	preempt_disable_notrace();

  	/*
  	 * Have to open code "rcu_dereference_sched()" because the
  	 * function graph tracer can be called when RCU is not
  	 * "watching".

  	 * Protected with schedule_on_each_cpu(ftrace_sync)

  	 */

  	notrace_hash = rcu_dereference_protected(ftrace_graph_notrace_hash,
  						 !preemptible());
  
  	if (ftrace_lookup_ip(notrace_hash, addr))

  		ret = 1;

  	preempt_enable_notrace();
  	return ret;

  }

  #else

  static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace)

  {
  	return 1;

  }

  
  static inline int ftrace_graph_notrace_addr(unsigned long addr)
  {
  	return 0;
  }

  static inline void ftrace_graph_addr_finish(struct ftrace_graph_ret *trace)
  { }

  #endif /* CONFIG_DYNAMIC_FTRACE */

  
  extern unsigned int fgraph_max_depth;
  
  static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace)
  {
  	/* trace it when it is-nested-in or is a function enabled. */

  	return !(trace_recursion_test(TRACE_GRAPH_BIT) ||
  		 ftrace_graph_addr(trace)) ||

  		(trace->depth < 0) ||
  		(fgraph_max_depth && trace->depth >= fgraph_max_depth);
  }

  #else /* CONFIG_FUNCTION_GRAPH_TRACER */

  static inline enum print_line_t

  print_graph_function_flags(struct trace_iterator *iter, u32 flags)

  {
  	return TRACE_TYPE_UNHANDLED;
  }

  #endif /* CONFIG_FUNCTION_GRAPH_TRACER */

  extern struct list_head ftrace_pids;

  #ifdef CONFIG_FUNCTION_TRACER

  
  #define FTRACE_PID_IGNORE	-1
  #define FTRACE_PID_TRACE	-2

  struct ftrace_func_command {
  	struct list_head	list;
  	char			*name;

  	int			(*func)(struct trace_array *tr,
  					struct ftrace_hash *hash,

  					char *func, char *cmd,
  					char *params, int enable);
  };

  extern bool ftrace_filter_param __initdata;

  static inline int ftrace_trace_task(struct trace_array *tr)

  {

  	return this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid) !=
  		FTRACE_PID_IGNORE;

  }

  extern int ftrace_is_dead(void);

  int ftrace_create_function_files(struct trace_array *tr,
  				 struct dentry *parent);
  void ftrace_destroy_function_files(struct trace_array *tr);

  int ftrace_allocate_ftrace_ops(struct trace_array *tr);
  void ftrace_free_ftrace_ops(struct trace_array *tr);

  void ftrace_init_global_array_ops(struct trace_array *tr);
  void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func);
  void ftrace_reset_array_ops(struct trace_array *tr);

  void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);

  void ftrace_init_tracefs_toplevel(struct trace_array *tr,
  				  struct dentry *d_tracer);

  void ftrace_clear_pids(struct trace_array *tr);

  int init_function_trace(void);

  void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);

  #else

  static inline int ftrace_trace_task(struct trace_array *tr)

  {
  	return 1;
  }

  static inline int ftrace_is_dead(void) { return 0; }

  static inline int
  ftrace_create_function_files(struct trace_array *tr,
  			     struct dentry *parent)
  {
  	return 0;
  }

  static inline int ftrace_allocate_ftrace_ops(struct trace_array *tr)
  {
  	return 0;
  }
  static inline void ftrace_free_ftrace_ops(struct trace_array *tr) { }

  static inline void ftrace_destroy_function_files(struct trace_array *tr) { }

  static inline __init void
  ftrace_init_global_array_ops(struct trace_array *tr) { }
  static inline void ftrace_reset_array_ops(struct trace_array *tr) { }

  static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }

  static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }

  static inline void ftrace_clear_pids(struct trace_array *tr) { }

  static inline int init_function_trace(void) { return 0; }

  static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }

  /* ftace_func_t type is not defined, use macro instead of static inline */
  #define ftrace_init_array_ops(tr, func) do { } while (0)

  #endif /* CONFIG_FUNCTION_TRACER */
  
  #if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)

  
  struct ftrace_probe_ops {
  	void			(*func)(unsigned long ip,
  					unsigned long parent_ip,

  					struct trace_array *tr,

  					struct ftrace_probe_ops *ops,

  					void *data);

  	int			(*init)(struct ftrace_probe_ops *ops,

  					struct trace_array *tr,

  					unsigned long ip, void *init_data,
  					void **data);

  	void			(*free)(struct ftrace_probe_ops *ops,

  					struct trace_array *tr,

  					unsigned long ip, void *data);

  	int			(*print)(struct seq_file *m,
  					 unsigned long ip,
  					 struct ftrace_probe_ops *ops,
  					 void *data);
  };

  struct ftrace_func_mapper;
  typedef int (*ftrace_mapper_func)(void *data);
  
  struct ftrace_func_mapper *allocate_ftrace_func_mapper(void);
  void **ftrace_func_mapper_find_ip(struct ftrace_func_mapper *mapper,
  					   unsigned long ip);
  int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
  			       unsigned long ip, void *data);
  void *ftrace_func_mapper_remove_ip(struct ftrace_func_mapper *mapper,
  				   unsigned long ip);
  void free_ftrace_func_mapper(struct ftrace_func_mapper *mapper,
  			     ftrace_mapper_func free_func);

  extern int

  register_ftrace_function_probe(char *glob, struct trace_array *tr,
  			       struct ftrace_probe_ops *ops, void *data);

  extern int

  unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
  				      struct ftrace_probe_ops *ops);

  extern void clear_ftrace_function_probes(struct trace_array *tr);

  int register_ftrace_command(struct ftrace_func_command *cmd);
  int unregister_ftrace_command(struct ftrace_func_command *cmd);

  void ftrace_create_filter_files(struct ftrace_ops *ops,
  				struct dentry *parent);
  void ftrace_destroy_filter_files(struct ftrace_ops *ops);

  
  extern int ftrace_set_filter(struct ftrace_ops *ops, unsigned char *buf,
  			     int len, int reset);
  extern int ftrace_set_notrace(struct ftrace_ops *ops, unsigned char *buf,
  			      int len, int reset);

  #else

  struct ftrace_func_command;
  
  static inline __init int register_ftrace_command(struct ftrace_func_command *cmd)
  {
  	return -EINVAL;
  }
  static inline __init int unregister_ftrace_command(char *cmd_name)
  {
  	return -EINVAL;
  }

  static inline void clear_ftrace_function_probes(struct trace_array *tr)
  {
  }

  /*
   * The ops parameter passed in is usually undefined.
   * This must be a macro.
   */
  #define ftrace_create_filter_files(ops, parent) do { } while (0)
  #define ftrace_destroy_filter_files(ops) do { } while (0)
  #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */

  bool ftrace_event_is_function(struct trace_event_call *call);

  /*

   * struct trace_parser - servers for reading the user input separated by spaces
   * @cont: set if the input is not complete - no final space char was found
   * @buffer: holds the parsed user input

   * @idx: user input length

   * @size: buffer size
   */
  struct trace_parser {
  	bool		cont;
  	char		*buffer;
  	unsigned	idx;
  	unsigned	size;
  };
  
  static inline bool trace_parser_loaded(struct trace_parser *parser)
  {
  	return (parser->idx != 0);
  }
  
  static inline bool trace_parser_cont(struct trace_parser *parser)
  {
  	return parser->cont;
  }
  
  static inline void trace_parser_clear(struct trace_parser *parser)
  {
  	parser->cont = false;
  	parser->idx = 0;
  }
  
  extern int trace_parser_get_init(struct trace_parser *parser, int size);
  extern void trace_parser_put(struct trace_parser *parser);
  extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
  	size_t cnt, loff_t *ppos);
  
  /*

   * Only create function graph options if function graph is configured.
   */
  #ifdef CONFIG_FUNCTION_GRAPH_TRACER
  # define FGRAPH_FLAGS						\

  		C(DISPLAY_GRAPH,	"display-graph"),

  #else
  # define FGRAPH_FLAGS

  #endif

  #ifdef CONFIG_BRANCH_TRACER
  # define BRANCH_FLAGS					\
  		C(BRANCH,		"branch"),
  #else
  # define BRANCH_FLAGS
  #endif

  #ifdef CONFIG_FUNCTION_TRACER
  # define FUNCTION_FLAGS						\

  		C(FUNCTION,		"function-trace"),	\
  		C(FUNC_FORK,		"function-fork"),

  # define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
  #else
  # define FUNCTION_FLAGS
  # define FUNCTION_DEFAULT_FLAGS		0UL

  # define TRACE_ITER_FUNC_FORK		0UL

  #endif

  #ifdef CONFIG_STACKTRACE
  # define STACK_FLAGS				\
  		C(STACKTRACE,		"stacktrace"),
  #else
  # define STACK_FLAGS
  #endif

  /*

   * trace_iterator_flags is an enumeration that defines bit
   * positions into trace_flags that controls the output.
   *
   * NOTE: These bits must match the trace_options array in

   *       trace.c (this macro guarantees it).

   */

  #define TRACE_FLAGS						\
  		C(PRINT_PARENT,		"print-parent"),	\
  		C(SYM_OFFSET,		"sym-offset"),		\
  		C(SYM_ADDR,		"sym-addr"),		\
  		C(VERBOSE,		"verbose"),		\
  		C(RAW,			"raw"),			\
  		C(HEX,			"hex"),			\
  		C(BIN,			"bin"),			\
  		C(BLOCK,		"block"),		\

  		C(PRINTK,		"trace_printk"),	\

  		C(ANNOTATE,		"annotate"),		\
  		C(USERSTACKTRACE,	"userstacktrace"),	\
  		C(SYM_USEROBJ,		"sym-userobj"),		\
  		C(PRINTK_MSGONLY,	"printk-msg-only"),	\
  		C(CONTEXT_INFO,		"context-info"),   /* Print pid/cpu/time */ \
  		C(LATENCY_FMT,		"latency-format"),	\

  		C(RECORD_CMD,		"record-cmd"),		\

  		C(RECORD_TGID,		"record-tgid"),		\

  		C(OVERWRITE,		"overwrite"),		\
  		C(STOP_ON_FREE,		"disable_on_free"),	\
  		C(IRQ_INFO,		"irq-info"),		\
  		C(MARKERS,		"markers"),		\

  		C(EVENT_FORK,		"event-fork"),		\

  		C(PAUSE_ON_TRACE,	"pause-on-trace"),	\

  		FUNCTION_FLAGS					\

  		FGRAPH_FLAGS					\

  		STACK_FLAGS					\

  		BRANCH_FLAGS

  /*
   * By defining C, we can make TRACE_FLAGS a list of bit names
   * that will define the bits for the flag masks.
   */
  #undef C
  #define C(a, b) TRACE_ITER_##a##_BIT

  enum trace_iterator_bits {
  	TRACE_FLAGS
  	/* Make sure we don't go more than we have bits for */
  	TRACE_ITER_LAST_BIT
  };

  
  /*
   * By redefining C, we can make TRACE_FLAGS a list of masks that
   * use the bits as defined above.
   */
  #undef C
  #define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT)
  
  enum trace_iterator_flags { TRACE_FLAGS };

  /*
   * TRACE_ITER_SYM_MASK masks the options in trace_flags that
   * control the output of kernel symbols.
   */
  #define TRACE_ITER_SYM_MASK \
  	(TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR)

  extern struct tracer nop_trace;

  #ifdef CONFIG_BRANCH_TRACER

  extern int enable_branch_tracing(struct trace_array *tr);
  extern void disable_branch_tracing(void);
  static inline int trace_branch_enable(struct trace_array *tr)

  {

  	if (tr->trace_flags & TRACE_ITER_BRANCH)

  		return enable_branch_tracing(tr);

  	return 0;
  }

  static inline void trace_branch_disable(void)

  {
  	/* due to races, always disable */

  	disable_branch_tracing();

  }
  #else

  static inline int trace_branch_enable(struct trace_array *tr)

  {
  	return 0;
  }

  static inline void trace_branch_disable(void)

  {
  }

  #endif /* CONFIG_BRANCH_TRACER */

  /* set ring buffers to default size if not already done so */
  int tracing_update_buffers(void);

  struct ftrace_event_field {
  	struct list_head	link;

  	const char		*name;
  	const char		*type;

  	int			filter_type;

  	int			offset;
  	int			size;

  	int			is_signed;

  };

  struct prog_entry;

  struct event_filter {

  	struct prog_entry __rcu	*prog;
  	char			*filter_string;

  };

  struct event_subsystem {
  	struct list_head	list;
  	const char		*name;

  	struct event_filter	*filter;

  	int			ref_count;

  };

  struct trace_subsystem_dir {

  	struct list_head		list;
  	struct event_subsystem		*subsystem;
  	struct trace_array		*tr;
  	struct dentry			*entry;
  	int				ref_count;
  	int				nr_events;
  };

  extern int call_filter_check_discard(struct trace_event_call *call, void *rec,

  				     struct trace_buffer *buffer,

  				     struct ring_buffer_event *event);

  void trace_buffer_unlock_commit_regs(struct trace_array *tr,

  				     struct trace_buffer *buffer,

  				     struct ring_buffer_event *event,
  				     unsigned long flags, int pc,
  				     struct pt_regs *regs);

  
  static inline void trace_buffer_unlock_commit(struct trace_array *tr,

  					      struct trace_buffer *buffer,

  					      struct ring_buffer_event *event,
  					      unsigned long flags, int pc)
  {
  	trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
  }

  DECLARE_PER_CPU(struct ring_buffer_event *, trace_buffered_event);
  DECLARE_PER_CPU(int, trace_buffered_event_cnt);
  void trace_buffered_event_disable(void);
  void trace_buffered_event_enable(void);
  
  static inline void

  __trace_event_discard_commit(struct trace_buffer *buffer,

  			     struct ring_buffer_event *event)
  {
  	if (this_cpu_read(trace_buffered_event) == event) {
  		/* Simply release the temp buffer */
  		this_cpu_dec(trace_buffered_event_cnt);
  		return;
  	}
  	ring_buffer_discard_commit(buffer, event);
  }

  /*
   * 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 will 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 trace_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, event);

  	if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
  	    (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
  	     !filter_match_preds(file->filter, entry))) {

  		__trace_event_discard_commit(buffer, event);

  		return true;
  	}

  	return false;

  }
  
  /**
   * 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 trace_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 trace_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);

  }

  #define FILTER_PRED_INVALID	((unsigned short)-1)
  #define FILTER_PRED_IS_RIGHT	(1 << 15)

  #define FILTER_PRED_FOLD	(1 << 15)

  /*
   * The max preds is the size of unsigned short with
   * two flags at the MSBs. One bit is used for both the IS_RIGHT
   * and FOLD flags. The other is reserved.
   *
   * 2^14 preds is way more than enough.
   */
  #define MAX_FILTER_PRED		16384

  struct filter_pred;

  struct regex;

  typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);

  typedef int (*regex_match_func)(char *str, struct regex *r, int len);

  enum regex_type {

  	MATCH_FULL = 0,

  	MATCH_FRONT_ONLY,
  	MATCH_MIDDLE_ONLY,
  	MATCH_END_ONLY,

  	MATCH_GLOB,