trace.h 43.7 KB
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#ifndef _LINUX_KERNEL_TRACE_H
#define _LINUX_KERNEL_TRACE_H

#include <linux/fs.h>
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#include <linux/atomic.h>
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#include <linux/sched.h>
#include <linux/clocksource.h>
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#include <linux/ring_buffer.h>
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#include <linux/mmiotrace.h>
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#include <linux/tracepoint.h>
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#include <linux/ftrace.h>
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#include <linux/hw_breakpoint.h>
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#include <linux/trace_seq.h>
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#include <linux/trace_events.h>
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#include <linux/compiler.h>
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#include <linux/trace_seq.h>
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#ifdef CONFIG_FTRACE_SYSCALLS
#include <asm/unistd.h>		/* For NR_SYSCALLS	     */
#include <asm/syscall.h>	/* some archs define it here */
#endif

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enum trace_type {
	__TRACE_FIRST_TYPE = 0,

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

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#undef __field
#define __field(type, item)		type	item;
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#undef __field_struct
#define __field_struct(type, item)	__field(type, item)
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#undef __field_desc
#define __field_desc(type, container, item)
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#undef __array
#define __array(type, item, size)	type	item[size];
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#undef __array_desc
#define __array_desc(type, container, item, size)
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#undef __dynamic_array
#define __dynamic_array(type, item)	type	item[];
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#undef F_STRUCT
#define F_STRUCT(args...)		args
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#undef FTRACE_ENTRY
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#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter)	\
	struct struct_name {						\
		struct trace_entry	ent;				\
		tstruct							\
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	}
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#undef FTRACE_ENTRY_DUP
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#define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter)
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#undef FTRACE_ENTRY_REG
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#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print,	\
			 filter, regfn) \
	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
		     filter)
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#include "trace_entries.h"
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/*
 * syscalls are special, and need special handling, this is why
 * they are not included in trace_entries.h
 */
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struct syscall_trace_enter {
	struct trace_entry	ent;
	int			nr;
	unsigned long		args[];
};

struct syscall_trace_exit {
	struct trace_entry	ent;
	int			nr;
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	long			ret;
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};

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struct kprobe_trace_entry_head {
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	struct trace_entry	ent;
	unsigned long		ip;
};

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

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/*
 * trace_flag_type is an enumeration that holds different
 * states when a trace occurs. These are:
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 *  IRQS_OFF		- interrupts were disabled
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 *  IRQS_NOSUPPORT	- arch does not support irqs_disabled_flags
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 *  NEED_RESCHED	- reschedule is requested
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 *  HARDIRQ		- inside an interrupt handler
 *  SOFTIRQ		- inside a softirq handler
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 */
enum trace_flag_type {
	TRACE_FLAG_IRQS_OFF		= 0x01,
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	TRACE_FLAG_IRQS_NOSUPPORT	= 0x02,
	TRACE_FLAG_NEED_RESCHED		= 0x04,
	TRACE_FLAG_HARDIRQ		= 0x08,
	TRACE_FLAG_SOFTIRQ		= 0x10,
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	TRACE_FLAG_PREEMPT_RESCHED	= 0x20,
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	TRACE_FLAG_NMI			= 0x40,
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};

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#define TRACE_BUF_SIZE		1024
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struct trace_array;

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/*
 * 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;
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	void			*buffer_page;	/* ring buffer spare */
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	unsigned long		entries;
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	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;
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	unsigned long		skipped_entries;
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	cycle_t			preempt_timestamp;
	pid_t			pid;
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	kuid_t			uid;
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	char			comm[TASK_COMM_LEN];
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	bool			ignore_pid;
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};

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

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#define TRACE_FLAGS_MAX_SIZE		32

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

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struct trace_pid_list {
	unsigned int			nr_pids;
	int				order;
	pid_t				*pids;
};

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/*
 * 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 {
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	struct list_head	list;
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	char			*name;
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	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;
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	bool			allocated_snapshot;
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	unsigned long		max_latency;
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#endif
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	struct trace_pid_list	__rcu *filtered_pids;
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	/*
	 * 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;
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	int			buffer_disabled;
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#ifdef CONFIG_FTRACE_SYSCALLS
	int			sys_refcount_enter;
	int			sys_refcount_exit;
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	struct trace_event_file __rcu *enter_syscall_files[NR_syscalls];
	struct trace_event_file __rcu *exit_syscall_files[NR_syscalls];
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#endif
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	int			stop_count;
	int			clock_id;
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	int			nr_topts;
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	struct tracer		*current_trace;
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	unsigned int		trace_flags;
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	unsigned char		trace_flags_index[TRACE_FLAGS_MAX_SIZE];
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	unsigned int		flags;
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	raw_spinlock_t		start_lock;
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	struct dentry		*dir;
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	struct dentry		*options;
	struct dentry		*percpu_dir;
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	struct dentry		*event_dir;
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	struct trace_options	*topts;
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	struct list_head	systems;
	struct list_head	events;
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	cpumask_var_t		tracing_cpumask; /* only trace on set CPUs */
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	int			ref;
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#ifdef CONFIG_FUNCTION_TRACER
	struct ftrace_ops	*ops;
	/* function tracing enabled */
	int			function_enabled;
#endif
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};

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enum {
	TRACE_ARRAY_FL_GLOBAL	= (1 << 0)
};

extern struct list_head ftrace_trace_arrays;

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extern struct mutex trace_types_lock;

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extern int trace_array_get(struct trace_array *tr);
extern void trace_array_put(struct trace_array *tr);

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/*
 * 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;

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	if (list_empty(&ftrace_trace_arrays))
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		return NULL;

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

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#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);	\
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		IF_ASSIGN(var, ent, struct userstack_entry, TRACE_USER_STACK);\
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		IF_ASSIGN(var, ent, struct print_entry, TRACE_PRINT);	\
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		IF_ASSIGN(var, ent, struct bprint_entry, TRACE_BPRINT);	\
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		IF_ASSIGN(var, ent, struct bputs_entry, TRACE_BPUTS);	\
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		IF_ASSIGN(var, ent, struct trace_mmiotrace_rw,		\
			  TRACE_MMIO_RW);				\
		IF_ASSIGN(var, ent, struct trace_mmiotrace_map,		\
			  TRACE_MMIO_MAP);				\
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		IF_ASSIGN(var, ent, struct trace_branch, TRACE_BRANCH); \
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		IF_ASSIGN(var, ent, struct ftrace_graph_ent_entry,	\
			  TRACE_GRAPH_ENT);		\
		IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,	\
			  TRACE_GRAPH_RET);		\
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		__ftrace_bad_type();					\
	} while (0)
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/*
 * 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 {
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	const char	*name; /* Will appear on the trace_options file */
	u32		bit; /* Mask assigned in val field in tracer_flags */
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};

/*
 * 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;
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	struct tracer_opt	*opts;
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	struct tracer		*trace;
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};

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

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

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/**
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 * struct tracer - a specific tracer and its callbacks to interact with tracefs
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 * @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
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 * @start: called when tracing is unpaused (echo 1 > tracing_on)
 * @stop: called when tracing is paused (echo 0 > tracing_on)
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 * @update_thresh: called when tracing_thresh is updated
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 * @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
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 * @pipe_close: called when the trace_pipe file is released
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 * @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
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 */
struct tracer {
	const char		*name;
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	int			(*init)(struct trace_array *tr);
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	void			(*reset)(struct trace_array *tr);
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	void			(*start)(struct trace_array *tr);
	void			(*stop)(struct trace_array *tr);
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	int			(*update_thresh)(struct trace_array *tr);
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	void			(*open)(struct trace_iterator *iter);
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	void			(*pipe_open)(struct trace_iterator *iter);
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	void			(*close)(struct trace_iterator *iter);
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	void			(*pipe_close)(struct trace_iterator *iter);
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	ssize_t			(*read)(struct trace_iterator *iter,
					struct file *filp, char __user *ubuf,
					size_t cnt, loff_t *ppos);
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	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);
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#ifdef CONFIG_FTRACE_STARTUP_TEST
	int			(*selftest)(struct tracer *trace,
					    struct trace_array *tr);
#endif
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	void			(*print_header)(struct seq_file *m);
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	enum print_line_t	(*print_line)(struct trace_iterator *iter);
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	/* If you handled the flag setting, return 0 */
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	int			(*set_flag)(struct trace_array *tr,
					    u32 old_flags, u32 bit, int set);
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	/* Return 0 if OK with change, else return non-zero */
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	int			(*flag_changed)(struct trace_array *tr,
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						u32 mask, int set);
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	struct tracer		*next;
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	struct tracer_flags	*flags;
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	int			enabled;
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	int			ref;
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	bool			print_max;
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	bool			allow_instances;
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#ifdef CONFIG_TRACER_MAX_TRACE
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	bool			use_max_tr;
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#endif
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};

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/* Only current can touch trace_recursion */

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/*
 * 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 suppport 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.
 */
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enum {
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	TRACE_BUFFER_BIT,
	TRACE_BUFFER_NMI_BIT,
	TRACE_BUFFER_IRQ_BIT,
	TRACE_BUFFER_SIRQ_BIT,

	/* Start of function recursion bits */
	TRACE_FTRACE_BIT,
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	TRACE_FTRACE_NMI_BIT,
	TRACE_FTRACE_IRQ_BIT,
	TRACE_FTRACE_SIRQ_BIT,
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	/* INTERNAL_BITs must be greater than FTRACE_BITs */
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	TRACE_INTERNAL_BIT,
	TRACE_INTERNAL_NMI_BIT,
	TRACE_INTERNAL_IRQ_BIT,
	TRACE_INTERNAL_SIRQ_BIT,

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	TRACE_BRANCH_BIT,
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/*
 * 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.
 */
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	TRACE_IRQ_BIT,
};
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#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)))
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#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)))
		return -1;

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

	return bit;
}

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

	if (!bit)
		return;

	bit = 1 << bit;
	val &= ~bit;

	barrier();
	current->trace_recursion = val;
}

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static inline struct ring_buffer_iter *
trace_buffer_iter(struct trace_iterator *iter, int cpu)
{
	if (iter->buffer_iter && iter->buffer_iter[cpu])
		return iter->buffer_iter[cpu];
	return NULL;
}

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int tracer_init(struct tracer *t, struct trace_array *tr);
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int tracing_is_enabled(void);
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void tracing_reset(struct trace_buffer *buf, int cpu);
void tracing_reset_online_cpus(struct trace_buffer *buf);
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void tracing_reset_current(int cpu);
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void tracing_reset_all_online_cpus(void);
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int tracing_open_generic(struct inode *inode, struct file *filp);
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bool tracing_is_disabled(void);
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struct dentry *trace_create_file(const char *name,
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				 umode_t mode,
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				 struct dentry *parent,
				 void *data,
				 const struct file_operations *fops);

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struct dentry *tracing_init_dentry(void);
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struct ring_buffer_event;

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struct ring_buffer_event *
trace_buffer_lock_reserve(struct ring_buffer *buffer,
			  int type,
			  unsigned long len,
			  unsigned long flags,
			  int pc);
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struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
						struct trace_array_cpu *data);
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struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
					  int *ent_cpu, u64 *ent_ts);

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void __buffer_unlock_commit(struct ring_buffer *buffer,
			    struct ring_buffer_event *event);

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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);

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void trace_function(struct trace_array *tr,
		    unsigned long ip,
		    unsigned long parent_ip,
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		    unsigned long flags, int pc);
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void trace_graph_function(struct trace_array *tr,
		    unsigned long ip,
		    unsigned long parent_ip,
		    unsigned long flags, int pc);
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void trace_latency_header(struct seq_file *m);
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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);
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void trace_graph_return(struct ftrace_graph_ret *trace);
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int trace_graph_entry(struct ftrace_graph_ent *trace);
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void set_graph_array(struct trace_array *tr);
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void tracing_start_cmdline_record(void);
void tracing_stop_cmdline_record(void);
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int register_tracer(struct tracer *type);
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int is_tracing_stopped(void);
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loff_t tracing_lseek(struct file *file, loff_t offset, int whence);

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extern cpumask_var_t __read_mostly tracing_buffer_mask;

#define for_each_tracing_cpu(cpu)	\
	for_each_cpu(cpu, tracing_buffer_mask)
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extern unsigned long nsecs_to_usecs(unsigned long nsecs);

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extern unsigned long tracing_thresh;

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#ifdef CONFIG_TRACER_MAX_TRACE
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void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu);
void update_max_tr_single(struct trace_array *tr,
			  struct task_struct *tsk, int cpu);
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#endif /* CONFIG_TRACER_MAX_TRACE */
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#ifdef CONFIG_STACKTRACE
639
void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
640 641 642 643 644
			    int pc);

void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
		   int pc);
#else
645
static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
646 647 648 649 650 651 652 653 654
					  unsigned long flags, int pc)
{
}

static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
				 int skip, int pc)
{
}
#endif /* CONFIG_STACKTRACE */
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extern cycle_t ftrace_now(int cpu);
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658
extern void trace_find_cmdline(int pid, char comm[]);
659

660 661
#ifdef CONFIG_DYNAMIC_FTRACE
extern unsigned long ftrace_update_tot_cnt;
662
#endif
663 664
#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
extern int DYN_FTRACE_TEST_NAME(void);
665 666
#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
extern int DYN_FTRACE_TEST_NAME2(void);
667

668
extern bool ring_buffer_expanded;
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extern bool tracing_selftest_disabled;

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#ifdef CONFIG_FTRACE_STARTUP_TEST
extern int trace_selftest_startup_function(struct tracer *trace,
					   struct trace_array *tr);
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extern int trace_selftest_startup_function_graph(struct tracer *trace,
						 struct trace_array *tr);
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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);
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extern int trace_selftest_startup_nop(struct tracer *trace,
					 struct trace_array *tr);
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extern int trace_selftest_startup_sched_switch(struct tracer *trace,
					       struct trace_array *tr);
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extern int trace_selftest_startup_branch(struct tracer *trace,
					 struct trace_array *tr);
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/*
 * 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
/* Tracers are seldom changed. Optimize when selftests are disabled. */
#define __tracer_data		__read_mostly
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#endif /* CONFIG_FTRACE_STARTUP_TEST */

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extern void *head_page(struct trace_array_cpu *data);
702
extern unsigned long long ns2usecs(cycle_t nsec);
703
extern int
704
trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
705
extern int
706
trace_vprintk(unsigned long ip, const char *fmt, va_list args);
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extern int
trace_array_vprintk(struct trace_array *tr,
		    unsigned long ip, const char *fmt, va_list args);
int trace_array_printk(struct trace_array *tr,
		       unsigned long ip, const char *fmt, ...);
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int trace_array_printk_buf(struct ring_buffer *buffer,
			   unsigned long ip, const char *fmt, ...);
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void trace_printk_seq(struct trace_seq *s);
enum print_line_t print_trace_line(struct trace_iterator *iter);
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717 718
extern char trace_find_mark(unsigned long long duration);

719
/* Standard output formatting function used for function return traces */
720
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
721 722 723 724 725 726 727 728

/* 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
729
#define TRACE_GRAPH_PRINT_IRQS          0x40
730
#define TRACE_GRAPH_PRINT_TAIL          0x80
731 732
#define TRACE_GRAPH_SLEEP_TIME		0x100
#define TRACE_GRAPH_GRAPH_TIME		0x200
733 734
#define TRACE_GRAPH_PRINT_FILL_SHIFT	28
#define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
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736 737 738
extern void ftrace_graph_sleep_time_control(bool enable);
extern void ftrace_graph_graph_time_control(bool enable);

739 740 741
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);
742
extern void
743
trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
744 745 746 747 748 749 750 751 752
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);

753 754 755 756 757 758

#ifdef CONFIG_DYNAMIC_FTRACE
/* TODO: make this variable */
#define FTRACE_GRAPH_MAX_FUNCS		32
extern int ftrace_graph_count;
extern unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS];
759 760
extern int ftrace_graph_notrace_count;
extern unsigned long ftrace_graph_notrace_funcs[FTRACE_GRAPH_MAX_FUNCS];
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static inline int ftrace_graph_addr(unsigned long addr)
{
	int i;

766
	if (!ftrace_graph_count)
767 768 769
		return 1;

	for (i = 0; i < ftrace_graph_count; i++) {
770 771 772 773 774 775 776 777 778 779
		if (addr == ftrace_graph_funcs[i]) {
			/*
			 * 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);
780
			return 1;
781
		}
782 783 784 785
	}

	return 0;
}
786 787 788 789 790 791 792 793 794 795 796 797 798 799 800

static inline int ftrace_graph_notrace_addr(unsigned long addr)
{
	int i;

	if (!ftrace_graph_notrace_count)
		return 0;

	for (i = 0; i < ftrace_graph_notrace_count; i++) {
		if (addr == ftrace_graph_notrace_funcs[i])
			return 1;
	}

	return 0;
}
801
#else
802 803 804
static inline int ftrace_graph_addr(unsigned long addr)
{
	return 1;
805
}
806 807 808 809 810

static inline int ftrace_graph_notrace_addr(unsigned long addr)
{
	return 0;
}
811 812
#endif /* CONFIG_DYNAMIC_FTRACE */
#else /* CONFIG_FUNCTION_GRAPH_TRACER */
813
static inline enum print_line_t
814
print_graph_function_flags(struct trace_iterator *iter, u32 flags)
815 816 817
{
	return TRACE_TYPE_UNHANDLED;
}
818
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
819

820
extern struct list_head ftrace_pids;
821

822
#ifdef CONFIG_FUNCTION_TRACER
823
extern bool ftrace_filter_param __initdata;
824 825
static inline int ftrace_trace_task(struct task_struct *task)
{
826
	if (list_empty(&ftrace_pids))
827 828 829 830
		return 1;

	return test_tsk_trace_trace(task);
}
831
extern int ftrace_is_dead(void);
832 833 834
int ftrace_create_function_files(struct trace_array *tr,
				 struct dentry *parent);
void ftrace_destroy_function_files(struct trace_array *tr);
835 836 837
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);
838
int using_ftrace_ops_list_func(void);
839 840 841 842 843
#else
static inline int ftrace_trace_task(struct task_struct *task)
{
	return 1;
}
844
static inline int ftrace_is_dead(void) { return 0; }
845 846 847 848 849 850 851
static inline int
ftrace_create_function_files(struct trace_array *tr,
			     struct dentry *parent)
{
	return 0;
}
static inline void ftrace_destroy_function_files(struct trace_array *tr) { }
852 853 854 855 856
static inline __init void
ftrace_init_global_array_ops(struct trace_array *tr) { }
static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
/* ftace_func_t type is not defined, use macro instead of static inline */
#define ftrace_init_array_ops(tr, func) do { } while (0)
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#endif /* CONFIG_FUNCTION_TRACER */

#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
void ftrace_create_filter_files(struct ftrace_ops *ops,
				struct dentry *parent);
void ftrace_destroy_filter_files(struct ftrace_ops *ops);
#else
/*
 * 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 */
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872
bool ftrace_event_is_function(struct trace_event_call *call);
873

874 875 876 877
/*
 * 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
878
 * @idx: user input length
879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908
 * @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);

909 910 911 912 913 914 915 916 917 918
/*
 * 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

919 920 921 922 923 924 925
#ifdef CONFIG_BRANCH_TRACER
# define BRANCH_FLAGS					\
		C(BRANCH,		"branch"),
#else
# define BRANCH_FLAGS
#endif

926 927 928 929 930 931 932 933 934
#ifdef CONFIG_FUNCTION_TRACER
# define FUNCTION_FLAGS						\
		C(FUNCTION,		"function-trace"),
# define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
#else
# define FUNCTION_FLAGS
# define FUNCTION_DEFAULT_FLAGS		0UL
#endif

935 936 937 938 939 940 941
#ifdef CONFIG_STACKTRACE
# define STACK_FLAGS				\
		C(STACKTRACE,		"stacktrace"),
#else
# define STACK_FLAGS
#endif

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/*
 * 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
947
 *       trace.c (this macro guarantees it).
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 */
949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969
#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(OVERWRITE,		"overwrite"),		\
		C(STOP_ON_FREE,		"disable_on_free"),	\
		C(IRQ_INFO,		"irq-info"),		\
		C(MARKERS,		"markers"),		\
970
		FUNCTION_FLAGS					\
971
		FGRAPH_FLAGS					\
972
		STACK_FLAGS					\
973
		BRANCH_FLAGS
974

975 976 977 978 979 980 981
/*
 * 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

982 983 984 985 986
enum trace_iterator_bits {
	TRACE_FLAGS
	/* Make sure we don't go more than we have bits for */
	TRACE_ITER_LAST_BIT
};
987 988 989 990 991 992 993 994 995

/*
 * 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 };
996

997 998 999 1000 1001 1002 1003
/*
 * 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)

1004 1005
extern struct tracer nop_trace;

1006
#ifdef CONFIG_BRANCH_TRACER
1007 1008 1009
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)
1010
{
1011
	if (tr->trace_flags & TRACE_ITER_BRANCH)
1012
		return enable_branch_tracing(tr);
1013 1014
	return 0;
}
1015
static inline void trace_branch_disable(void)
1016 1017
{
	/* due to races, always disable */
1018
	disable_branch_tracing();
1019 1020
}
#else
1021
static inline int trace_branch_enable(struct trace_array *tr)
1022 1023 1024
{
	return 0;
}
1025
static inline void trace_branch_disable(void)
1026 1027
{
}
1028
#endif /* CONFIG_BRANCH_TRACER */
1029

1030 1031 1032
/* set ring buffers to default size if not already done so */
int tracing_update_buffers(void);

1033 1034
struct ftrace_event_field {
	struct list_head	link;
1035 1036
	const char		*name;
	const char		*type;
1037
	int			filter_type;
1038 1039
	int			offset;
	int			size;
1040
	int			is_signed;
1041 1042
};

1043
struct event_filter {
1044 1045
	int			n_preds;	/* Number assigned */
	int			a_preds;	/* allocated */
1046
	struct filter_pred	*preds;
1047
	struct filter_pred	*root;
1048
	char			*filter_string;
1049 1050
};

1051 1052 1053
struct event_subsystem {
	struct list_head	list;
	const char		*name;
1054
	struct event_filter	*filter;
1055
	int			ref_count;
1056 1057
};

1058
struct trace_subsystem_dir {
1059 1060 1061 1062 1063 1064 1065 1066
	struct list_head		list;
	struct event_subsystem		*subsystem;
	struct trace_array		*tr;
	struct dentry			*entry;
	int				ref_count;
	int				nr_events;
};

1067 1068
#define FILTER_PRED_INVALID	((unsigned short)-1)
#define FILTER_PRED_IS_RIGHT	(1 << 15)
1069
#define FILTER_PRED_FOLD	(1 << 15)
1070

1071 1072 1073 1074 1075 1076 1077 1078
/*
 * 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
1079

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struct filter_pred;
1081
struct regex;
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1083
typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
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1084

1085 1086
typedef int (*regex_match_func)(char *str, struct regex *r, int len);

1087
enum regex_type {
1088
	MATCH_FULL = 0,
1089 1090 1091 1092 1093
	MATCH_FRONT_ONLY,
	MATCH_MIDDLE_ONLY,
	MATCH_END_ONLY,
};

1094 1095 1096 1097 1098 1099 1100
struct regex {
	char			pattern[MAX_FILTER_STR_VAL];
	int			len;
	int			field_len;
	regex_match_func	match;
};

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struct filter_pred {
1102 1103 1104
	filter_pred_fn_t 	fn;
	u64 			val;
	struct regex		regex;
1105
	unsigned short		*ops;
1106
	struct ftrace_event_field *field;
1107 1108 1109
	int 			offset;
	int 			not;
	int 			op;
1110 1111 1112 1113
	unsigned short		index;
	unsigned short		parent;
	unsigned short		left;
	unsigned short		right;
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Tom Zanussi 已提交
1114 1115
};

1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127
static inline bool is_string_field(struct ftrace_event_field *field)
{
	return field->filter_type == FILTER_DYN_STRING ||
	       field->filter_type == FILTER_STATIC_STRING ||
	       field->filter_type == FILTER_PTR_STRING;
}

static inline bool is_function_field(struct ftrace_event_field *field)
{
	return field->filter_type == FILTER_TRACE_FN;
}

1128 1129
extern enum regex_type
filter_parse_regex(char *buff, int len, char **search, int *not);
1130
extern void print_event_filter(struct trace_event_file *file,
1131
			       struct trace_seq *s);
1132
extern int apply_event_filter(struct trace_event_file *file,
1133
			      char *filter_string);
1134
extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1135 1136
					char *filter_string);
extern void print_subsystem_event_filter(struct event_subsystem *system,
1137
					 struct trace_seq *s);
1138
extern int filter_assign_type(const char *type);
1139
extern int create_event_filter(struct trace_event_call *call,
1140 1141 1142
			       char *filter_str, bool set_str,
			       struct event_filter **filterp);
extern void free_event_filter(struct event_filter *filter);
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Tom Zanussi 已提交
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1144
struct ftrace_event_field *
1145
trace_find_event_field(struct trace_event_call *call, char *name);
1146

1147
extern void trace_event_enable_cmd_record(bool enable);
1148
extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1149
extern int event_trace_del_tracer(struct trace_array *tr);
1150

1151 1152 1153
extern struct trace_event_file *find_event_file(struct trace_array *tr,
						const char *system,
						const char *event);
1154

1155 1156 1157 1158 1159
static inline void *event_file_data(struct file *filp)
{
	return ACCESS_ONCE(file_inode(filp)->i_private);
}

1160
extern struct mutex event_mutex;
1161
extern struct list_head ftrace_events;
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Peter Zijlstra 已提交
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1163 1164 1165 1166 1167 1168 1169 1170 1171 1172
extern const struct file_operations event_trigger_fops;

extern int register_trigger_cmds(void);
extern void clear_event_triggers(struct trace_array *tr);

struct event_trigger_data {
	unsigned long			count;
	int				ref;
	struct event_trigger_ops	*ops;
	struct event_command		*cmd_ops;
1173
	struct event_filter __rcu	*filter;
1174 1175
	char				*filter_str;
	void				*private_data;
1176
	bool				paused;
1177 1178 1179
	struct list_head		list;
};

1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193
extern void trigger_data_free(struct event_trigger_data *data);
extern int event_trigger_init(struct event_trigger_ops *ops,
			      struct event_trigger_data *data);
extern int trace_event_trigger_enable_disable(struct trace_event_file *file,
					      int trigger_enable);
extern void update_cond_flag(struct trace_event_file *file);
extern void unregister_trigger(char *glob, struct event_trigger_ops *ops,
			       struct event_trigger_data *test,
			       struct trace_event_file *file);
extern int set_trigger_filter(char *filter_str,
			      struct event_trigger_data *trigger_data,
			      struct trace_event_file *file);
extern int register_event_command(struct event_command *cmd);

1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205
/**
 * struct event_trigger_ops - callbacks for trace event triggers
 *
 * The methods in this structure provide per-event trigger hooks for
 * various trigger operations.
 *
 * All the methods below, except for @init() and @free(), must be
 * implemented.
 *
 * @func: The trigger 'probe' function called when the triggering
 *	event occurs.  The data passed into this callback is the data
 *	that was supplied to the event_command @reg() function that
1206 1207
 *	registered the trigger (see struct event_command) along with
 *	the trace record, rec.
1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231
 *
 * @init: An optional initialization function called for the trigger
 *	when the trigger is registered (via the event_command reg()
 *	function).  This can be used to perform per-trigger
 *	initialization such as incrementing a per-trigger reference
 *	count, for instance.  This is usually implemented by the
 *	generic utility function @event_trigger_init() (see
 *	trace_event_triggers.c).
 *
 * @free: An optional de-initialization function called for the
 *	trigger when the trigger is unregistered (via the
 *	event_command @reg() function).  This can be used to perform
 *	per-trigger de-initialization such as decrementing a
 *	per-trigger reference count and freeing corresponding trigger
 *	data, for instance.  This is usually implemented by the
 *	generic utility function @event_trigger_free() (see
 *	trace_event_triggers.c).
 *
 * @print: The callback function invoked to have the trigger print
 *	itself.  This is usually implemented by a wrapper function
 *	that calls the generic utility function @event_trigger_print()
 *	(see trace_event_triggers.c).
 */
struct event_trigger_ops {
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	void			(*func)(struct event_trigger_data *data,
					void *rec);
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	int			(*init)(struct event_trigger_ops *ops,
					struct event_trigger_data *data);
	void			(*free)(struct event_trigger_ops *ops,
					struct event_trigger_data *data);
	int			(*print)(struct seq_file *m,
					 struct event_trigger_ops *ops,
					 struct event_trigger_data *data);
};

/**
 * struct event_command - callbacks and data members for event commands
 *
 * Event commands are invoked by users by writing the command name
 * into the 'trigger' file associated with a trace event.  The
 * parameters associated with a specific invocation of an event
 * command are used to create an event trigger instance, which is
 * added to the list of trigger instances associated with that trace
 * event.  When the event is hit, the set of triggers associated with
 * that event is invoked.
 *
 * The data members in this structure provide per-event command data
 * for various event commands.
 *
 * All the data members below, except for @post_trigger, must be set
 * for each event command.
 *
 * @name: The unique name that identifies the event command.  This is
 *	the name used when setting triggers via trigger files.
 *
 * @trigger_type: A unique id that identifies the event command
 *	'type'.  This value has two purposes, the first to ensure that
 *	only one trigger of the same type can be set at a given time
 *	for a particular event e.g. it doesn't make sense to have both
 *	a traceon and traceoff trigger attached to a single event at
 *	the same time, so traceon and traceoff have the same type
 *	though they have different names.  The @trigger_type value is
 *	also used as a bit value for deferring the actual trigger
 *	action until after the current event is finished.  Some
 *	commands need to do this if they themselves log to the trace
 *	buffer (see the @post_trigger() member below).  @trigger_type
 *	values are defined by adding new values to the trigger_type
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 *	enum in include/linux/trace_events.h.
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 *
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 * @flags: See the enum event_command_flags below.
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 *
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 * All the methods below, except for @set_filter() and @unreg_all(),
 * must be implemented.
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 *
 * @func: The callback function responsible for parsing and
 *	registering the trigger written to the 'trigger' file by the
 *	user.  It allocates the trigger instance and registers it with
 *	the appropriate trace event.  It makes use of the other
 *	event_command callback functions to orchestrate this, and is
 *	usually implemented by the generic utility function
 *	@event_trigger_callback() (see trace_event_triggers.c).
 *
 * @reg: Adds the trigger to the list of triggers associated with the
 *	event, and enables the event trigger itself, after
 *	initializing it (via the event_trigger_ops @init() function).
 *	This is also where commands can use the @trigger_type value to
 *	make the decision as to whether or not multiple instances of
 *	the trigger should be allowed.  This is usually implemented by
 *	the generic utility function @register_trigger() (see
 *	trace_event_triggers.c).
 *
 * @unreg: Removes the trigger from the list of triggers associated
 *	with the event, and disables the event trigger itself, after
 *	initializing it (via the event_trigger_ops @free() function).
 *	This is usually implemented by the generic utility function
 *	@unregister_trigger() (see trace_event_triggers.c).
 *
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 * @unreg_all: An optional function called to remove all the triggers
 *	from the list of triggers associated with the event.  Called
 *	when a trigger file is opened in truncate mode.
 *
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 * @set_filter: An optional function called to parse and set a filter
 *	for the trigger.  If no @set_filter() method is set for the
 *	event command, filters set by the user for the command will be
 *	ignored.  This is usually implemented by the generic utility
 *	function @set_trigger_filter() (see trace_event_triggers.c).
 *
 * @get_trigger_ops: The callback function invoked to retrieve the
 *	event_trigger_ops implementation associated with the command.
 */
struct event_command {
	struct list_head	list;
	char			*name;
	enum event_trigger_type	trigger_type;
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	int			flags;
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	int			(*func)(struct event_command *cmd_ops,
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					struct trace_event_file *file,
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					char *glob, char *cmd, char *params);
	int			(*reg)(char *glob,
				       struct event_trigger_ops *ops,
				       struct event_trigger_data *data,
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				       struct trace_event_file *file);
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	void			(*unreg)(char *glob,
					 struct event_trigger_ops *ops,
					 struct event_trigger_data *data,
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					 struct trace_event_file *file);
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	void			(*unreg_all)(struct trace_event_file *file);
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	int			(*set_filter)(char *filter_str,
					      struct event_trigger_data *data,
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					      struct trace_event_file *file);
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	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
};

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/**
 * enum event_command_flags - flags for struct event_command
 *
 * @POST_TRIGGER: A flag that says whether or not this command needs
 *	to have its action delayed until after the current event has
 *	been closed.  Some triggers need to avoid being invoked while
 *	an event is currently in the process of being logged, since
 *	the trigger may itself log data into the trace buffer.  Thus
 *	we make sure the current event is committed before invoking
 *	those triggers.  To do that, the trigger invocation is split
 *	in two - the first part checks the filter using the current
 *	trace record; if a command has the @post_trigger flag set, it
 *	sets a bit for itself in the return value, otherwise it
 *	directly invokes the trigger.  Once all commands have been
 *	either invoked or set their return flag, the current record is
 *	either committed or discarded.  At that point, if any commands
 *	have deferred their triggers, those commands are finally
 *	invoked following the close of the current event.  In other
 *	words, if the event_trigger_ops @func() probe implementation
 *	itself logs to the trace buffer, this flag should be set,
 *	otherwise it can be left unspecified.
 *
 * @NEEDS_REC: A flag that says whether or not this command needs
 *	access to the trace record in order to perform its function,
 *	regardless of whether or not it has a filter associated with
 *	it (filters make a trigger require access to the trace record
 *	but are not always present).
 */
enum event_command_flags {
	EVENT_CMD_FL_POST_TRIGGER	= 1,
	EVENT_CMD_FL_NEEDS_REC		= 2,
};

static inline bool event_command_post_trigger(struct event_command *cmd_ops)
{
	return cmd_ops->flags & EVENT_CMD_FL_POST_TRIGGER;
}

static inline bool event_command_needs_rec(struct event_command *cmd_ops)
{
	return cmd_ops->flags & EVENT_CMD_FL_NEEDS_REC;
}

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extern int trace_event_enable_disable(struct trace_event_file *file,
1385
				      int enable, int soft_disable);
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extern int tracing_alloc_snapshot(void);
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extern const char *__start___trace_bprintk_fmt[];
extern const char *__stop___trace_bprintk_fmt[];

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extern const char *__start___tracepoint_str[];
extern const char *__stop___tracepoint_str[];

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void trace_printk_control(bool enabled);
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void trace_printk_init_buffers(void);
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void trace_printk_start_comm(void);
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int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
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int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
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/*
 * Normal trace_printk() and friends allocates special buffers
 * to do the manipulation, as well as saves the print formats
 * into sections to display. But the trace infrastructure wants
 * to use these without the added overhead at the price of being
 * a bit slower (used mainly for warnings, where we don't care
 * about performance). The internal_trace_puts() is for such
 * a purpose.
 */
#define internal_trace_puts(str) __trace_puts(_THIS_IP_, str, strlen(str))

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#undef FTRACE_ENTRY
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#define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)	\
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	extern struct trace_event_call					\
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	__aligned(4) event_##call;
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#undef FTRACE_ENTRY_DUP
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#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter)	\
	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
		     filter)
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#include "trace_entries.h"
1420

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#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
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int perf_ftrace_event_register(struct trace_event_call *call,
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			       enum trace_reg type, void *data);
#else
#define perf_ftrace_event_register NULL
1426
#endif
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#ifdef CONFIG_FTRACE_SYSCALLS
void init_ftrace_syscalls(void);
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Tom Zanussi 已提交
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const char *get_syscall_name(int syscall);
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#else
static inline void init_ftrace_syscalls(void) { }
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Tom Zanussi 已提交
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static inline const char *get_syscall_name(int syscall)
{
	return NULL;
}
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#endif

#ifdef CONFIG_EVENT_TRACING
void trace_event_init(void);
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void trace_event_enum_update(struct trace_enum_map **map, int len);
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#else
static inline void __init trace_event_init(void) { }
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static inline void trace_event_enum_update(struct trace_enum_map **map, int len) { }
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#endif

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extern struct trace_iterator *tracepoint_print_iter;
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#endif /* _LINUX_KERNEL_TRACE_H */