trace.h 55.7 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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#include <linux/glob.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_HWLAT,
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	TRACE_RAW_DATA,
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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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#undef FTRACE_ENTRY_PACKED
#define FTRACE_ENTRY_PACKED(name, struct_name, id, tstruct, print,	\
			    filter)					\
	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
		     filter) __packed

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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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	u64			preempt_timestamp;
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	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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#ifdef CONFIG_FUNCTION_TRACER
	bool			ftrace_ignore_pid;
#endif
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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;
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	u64				time_start;
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	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 {
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	int				pid_max;
	unsigned long			*pids;
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};

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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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#endif
#if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)
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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;
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	struct trace_pid_list	__rcu *function_pids;
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#ifdef CONFIG_DYNAMIC_FTRACE
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	/* All of these are protected by the ftrace_lock */
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	struct list_head	func_probes;
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	struct list_head	mod_trace;
	struct list_head	mod_notrace;
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#endif
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	/* 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 hwlat_entry, TRACE_HWLAT);	\
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		IF_ASSIGN(var, ent, struct raw_data_entry, TRACE_RAW_DATA);\
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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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int tracer_tracing_is_on(struct trace_array *tr);
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void tracer_tracing_on(struct trace_array *tr);
void tracer_tracing_off(struct trace_array *tr);
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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 trace_buffer_unlock_commit_nostack(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);
632
void trace_latency_header(struct seq_file *m);
633 634 635
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);
636

637
void trace_graph_return(struct ftrace_graph_ret *trace);
638
int trace_graph_entry(struct ftrace_graph_ent *trace);
639
void set_graph_array(struct trace_array *tr);
640

641 642
void tracing_start_cmdline_record(void);
void tracing_stop_cmdline_record(void);
643
int register_tracer(struct tracer *type);
644
int is_tracing_stopped(void);
645

646 647
loff_t tracing_lseek(struct file *file, loff_t offset, int whence);

648 649 650 651
extern cpumask_var_t __read_mostly tracing_buffer_mask;

#define for_each_tracing_cpu(cpu)	\
	for_each_cpu(cpu, tracing_buffer_mask)
652 653 654

extern unsigned long nsecs_to_usecs(unsigned long nsecs);

655 656
extern unsigned long tracing_thresh;

657
/* PID filtering */
658 659 660

extern int pid_max;

661 662 663 664 665 666 667
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 task_struct *task);
void trace_filter_add_remove_task(struct trace_pid_list *pid_list,
				  struct task_struct *self,
				  struct task_struct *task);
668 669 670
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);
671 672 673 674
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);
675

676
#ifdef CONFIG_TRACER_MAX_TRACE
677 678 679
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);
680
#endif /* CONFIG_TRACER_MAX_TRACE */
681

682
#ifdef CONFIG_STACKTRACE
683
void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags,
684 685 686 687 688
			    int pc);

void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
		   int pc);
#else
689
static inline void ftrace_trace_userstack(struct ring_buffer *buffer,
690 691 692 693 694 695 696 697 698
					  unsigned long flags, int pc)
{
}

static inline void __trace_stack(struct trace_array *tr, unsigned long flags,
				 int skip, int pc)
{
}
#endif /* CONFIG_STACKTRACE */
699

700
extern u64 ftrace_now(int cpu);
701

702
extern void trace_find_cmdline(int pid, char comm[]);
703
extern void trace_event_follow_fork(struct trace_array *tr, bool enable);
704

705 706
#ifdef CONFIG_DYNAMIC_FTRACE
extern unsigned long ftrace_update_tot_cnt;
707 708 709
void ftrace_init_trace_array(struct trace_array *tr);
#else
static inline void ftrace_init_trace_array(struct trace_array *tr) { }
710
#endif
711 712
#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
extern int DYN_FTRACE_TEST_NAME(void);
713 714
#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
extern int DYN_FTRACE_TEST_NAME2(void);
715

716
extern bool ring_buffer_expanded;
717 718
extern bool tracing_selftest_disabled;

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719 720 721
#ifdef CONFIG_FTRACE_STARTUP_TEST
extern int trace_selftest_startup_function(struct tracer *trace,
					   struct trace_array *tr);
722 723
extern int trace_selftest_startup_function_graph(struct tracer *trace,
						 struct trace_array *tr);
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Steven Rostedt 已提交
724 725 726 727 728 729 730 731
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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Steven Noonan 已提交
732 733
extern int trace_selftest_startup_nop(struct tracer *trace,
					 struct trace_array *tr);
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734 735
extern int trace_selftest_startup_sched_switch(struct tracer *trace,
					       struct trace_array *tr);
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736 737
extern int trace_selftest_startup_branch(struct tracer *trace,
					 struct trace_array *tr);
738 739 740 741 742 743 744 745 746
/*
 * 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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747 748
#endif /* CONFIG_FTRACE_STARTUP_TEST */

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749
extern void *head_page(struct trace_array_cpu *data);
750
extern unsigned long long ns2usecs(u64 nsec);
751
extern int
752
trace_vbprintk(unsigned long ip, const char *fmt, va_list args);
753
extern int
754
trace_vprintk(unsigned long ip, const char *fmt, va_list args);
755 756 757 758 759
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, ...);
760 761
int trace_array_printk_buf(struct ring_buffer *buffer,
			   unsigned long ip, const char *fmt, ...);
762 763
void trace_printk_seq(struct trace_seq *s);
enum print_line_t print_trace_line(struct trace_iterator *iter);
I
Ingo Molnar 已提交
764

765 766
extern char trace_find_mark(unsigned long long duration);

767 768 769 770 771 772 773 774 775
struct ftrace_hash;

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

776 777 778 779 780 781 782 783 784 785
struct ftrace_hash {
	unsigned long		size_bits;
	struct hlist_head	*buckets;
	unsigned long		count;
	struct rcu_head		rcu;
};

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

786
static __always_inline bool ftrace_hash_empty(struct ftrace_hash *hash)
787 788 789 790
{
	return !hash || !hash->count;
}

791
/* Standard output formatting function used for function return traces */
792
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
793 794 795 796 797 798 799 800

/* 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
801
#define TRACE_GRAPH_PRINT_IRQS          0x40
802
#define TRACE_GRAPH_PRINT_TAIL          0x80
803 804
#define TRACE_GRAPH_SLEEP_TIME		0x100
#define TRACE_GRAPH_GRAPH_TIME		0x200
805 806
#define TRACE_GRAPH_PRINT_FILL_SHIFT	28
#define TRACE_GRAPH_PRINT_FILL_MASK	(0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT)
807

808 809 810
extern void ftrace_graph_sleep_time_control(bool enable);
extern void ftrace_graph_graph_time_control(bool enable);

811 812 813
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);
814
extern void
815
trace_print_graph_duration(unsigned long long duration, struct trace_seq *s);
816 817 818 819 820 821 822 823 824
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);

825
#ifdef CONFIG_DYNAMIC_FTRACE
826 827
extern struct ftrace_hash *ftrace_graph_hash;
extern struct ftrace_hash *ftrace_graph_notrace_hash;
828 829 830

static inline int ftrace_graph_addr(unsigned long addr)
{
831 832 833 834 835 836 837
	int ret = 0;

	preempt_disable_notrace();

	if (ftrace_hash_empty(ftrace_graph_hash)) {
		ret = 1;
		goto out;
838 839
	}

840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855
	if (ftrace_lookup_ip(ftrace_graph_hash, addr)) {
		/*
		 * 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;
856
}
857 858 859

static inline int ftrace_graph_notrace_addr(unsigned long addr)
{
860
	int ret = 0;
861

862
	preempt_disable_notrace();
863

864 865
	if (ftrace_lookup_ip(ftrace_graph_notrace_hash, addr))
		ret = 1;
866

867 868
	preempt_enable_notrace();
	return ret;
869
}
870
#else
871 872 873
static inline int ftrace_graph_addr(unsigned long addr)
{
	return 1;
874
}
875 876 877 878 879

static inline int ftrace_graph_notrace_addr(unsigned long addr)
{
	return 0;
}
880
#endif /* CONFIG_DYNAMIC_FTRACE */
881 882 883 884 885 886 887 888 889 890 891

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

892
#else /* CONFIG_FUNCTION_GRAPH_TRACER */
893
static inline enum print_line_t
894
print_graph_function_flags(struct trace_iterator *iter, u32 flags)
895 896 897
{
	return TRACE_TYPE_UNHANDLED;
}
898
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
899

900
extern struct list_head ftrace_pids;
901

902
#ifdef CONFIG_FUNCTION_TRACER
903 904 905
struct ftrace_func_command {
	struct list_head	list;
	char			*name;
906 907
	int			(*func)(struct trace_array *tr,
					struct ftrace_hash *hash,
908 909 910
					char *func, char *cmd,
					char *params, int enable);
};
911
extern bool ftrace_filter_param __initdata;
912
static inline int ftrace_trace_task(struct trace_array *tr)
913
{
914
	return !this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid);
915
}
916
extern int ftrace_is_dead(void);
917 918 919
int ftrace_create_function_files(struct trace_array *tr,
				 struct dentry *parent);
void ftrace_destroy_function_files(struct trace_array *tr);
920 921 922
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);
923
int using_ftrace_ops_list_func(void);
924
void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer);
925 926
void ftrace_init_tracefs_toplevel(struct trace_array *tr,
				  struct dentry *d_tracer);
927
void ftrace_clear_pids(struct trace_array *tr);
928
int init_function_trace(void);
929
void ftrace_pid_follow_fork(struct trace_array *tr, bool enable);
930
#else
931
static inline int ftrace_trace_task(struct trace_array *tr)
932 933 934
{
	return 1;
}
935
static inline int ftrace_is_dead(void) { return 0; }
936 937 938 939 940 941 942
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) { }
943 944 945
static inline __init void
ftrace_init_global_array_ops(struct trace_array *tr) { }
static inline void ftrace_reset_array_ops(struct trace_array *tr) { }
946
static inline void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d) { }
947
static inline void ftrace_init_tracefs_toplevel(struct trace_array *tr, struct dentry *d) { }
948
static inline void ftrace_clear_pids(struct trace_array *tr) { }
949
static inline int init_function_trace(void) { return 0; }
950
static inline void ftrace_pid_follow_fork(struct trace_array *tr, bool enable) { }
951 952
/* ftace_func_t type is not defined, use macro instead of static inline */
#define ftrace_init_array_ops(tr, func) do { } while (0)
953 954 955
#endif /* CONFIG_FUNCTION_TRACER */

#if defined(CONFIG_FUNCTION_TRACER) && defined(CONFIG_DYNAMIC_FTRACE)
956 957 958 959

struct ftrace_probe_ops {
	void			(*func)(unsigned long ip,
					unsigned long parent_ip,
960
					struct trace_array *tr,
961
					struct ftrace_probe_ops *ops,
962
					void *data);
963
	int			(*init)(struct ftrace_probe_ops *ops,
964
					struct trace_array *tr,
965 966
					unsigned long ip, void *init_data,
					void **data);
967
	void			(*free)(struct ftrace_probe_ops *ops,
968
					struct trace_array *tr,
969
					unsigned long ip, void *data);
970 971 972 973 974 975
	int			(*print)(struct seq_file *m,
					 unsigned long ip,
					 struct ftrace_probe_ops *ops,
					 void *data);
};

976 977 978 979 980 981 982 983 984 985 986 987 988
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);

989
extern int
990 991
register_ftrace_function_probe(char *glob, struct trace_array *tr,
			       struct ftrace_probe_ops *ops, void *data);
992
extern int
993 994
unregister_ftrace_function_probe_func(char *glob, struct trace_array *tr,
				      struct ftrace_probe_ops *ops);
995
extern void clear_ftrace_function_probes(struct trace_array *tr);
996

997 998 999
int register_ftrace_command(struct ftrace_func_command *cmd);
int unregister_ftrace_command(struct ftrace_func_command *cmd);

1000 1001 1002 1003
void ftrace_create_filter_files(struct ftrace_ops *ops,
				struct dentry *parent);
void ftrace_destroy_filter_files(struct ftrace_ops *ops);
#else
1004 1005 1006 1007 1008 1009 1010 1011 1012 1013
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;
}
1014 1015 1016 1017
static inline void clear_ftrace_function_probes(struct trace_array *tr)
{
}

1018 1019 1020 1021 1022 1023 1024
/*
 * 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 */
1025

1026
bool ftrace_event_is_function(struct trace_event_call *call);
1027

1028 1029 1030 1031
/*
 * 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
1032
 * @idx: user input length
1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062
 * @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);

1063 1064 1065 1066 1067 1068 1069 1070 1071 1072
/*
 * 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

1073 1074 1075 1076 1077 1078 1079
#ifdef CONFIG_BRANCH_TRACER
# define BRANCH_FLAGS					\
		C(BRANCH,		"branch"),
#else
# define BRANCH_FLAGS
#endif

1080 1081
#ifdef CONFIG_FUNCTION_TRACER
# define FUNCTION_FLAGS						\
1082 1083
		C(FUNCTION,		"function-trace"),	\
		C(FUNC_FORK,		"function-fork"),
1084 1085 1086 1087
# define FUNCTION_DEFAULT_FLAGS		TRACE_ITER_FUNCTION
#else
# define FUNCTION_FLAGS
# define FUNCTION_DEFAULT_FLAGS		0UL
1088
# define TRACE_ITER_FUNC_FORK		0UL
1089 1090
#endif

1091 1092 1093 1094 1095 1096 1097
#ifdef CONFIG_STACKTRACE
# define STACK_FLAGS				\
		C(STACKTRACE,		"stacktrace"),
#else
# define STACK_FLAGS
#endif

S
Steven Rostedt 已提交
1098 1099 1100 1101 1102
/*
 * 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
1103
 *       trace.c (this macro guarantees it).
S
Steven Rostedt 已提交
1104
 */
1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125
#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"),		\
1126
		C(EVENT_FORK,		"event-fork"),		\
1127
		FUNCTION_FLAGS					\
1128
		FGRAPH_FLAGS					\
1129
		STACK_FLAGS					\
1130
		BRANCH_FLAGS
1131

1132 1133 1134 1135 1136 1137 1138
/*
 * 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

1139 1140 1141 1142 1143
enum trace_iterator_bits {
	TRACE_FLAGS
	/* Make sure we don't go more than we have bits for */
	TRACE_ITER_LAST_BIT
};
1144 1145 1146 1147 1148 1149 1150 1151 1152

/*
 * 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 };
1153

1154 1155 1156 1157 1158 1159 1160
/*
 * 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)

1161 1162
extern struct tracer nop_trace;

1163
#ifdef CONFIG_BRANCH_TRACER
1164 1165 1166
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)
1167
{
1168
	if (tr->trace_flags & TRACE_ITER_BRANCH)
1169
		return enable_branch_tracing(tr);
1170 1171
	return 0;
}
1172
static inline void trace_branch_disable(void)
1173 1174
{
	/* due to races, always disable */
1175
	disable_branch_tracing();
1176 1177
}
#else
1178
static inline int trace_branch_enable(struct trace_array *tr)
1179 1180 1181
{
	return 0;
}
1182
static inline void trace_branch_disable(void)
1183 1184
{
}
1185
#endif /* CONFIG_BRANCH_TRACER */
1186

1187 1188 1189
/* set ring buffers to default size if not already done so */
int tracing_update_buffers(void);

1190 1191
struct ftrace_event_field {
	struct list_head	link;
1192 1193
	const char		*name;
	const char		*type;
1194
	int			filter_type;
1195 1196
	int			offset;
	int			size;
1197
	int			is_signed;
1198 1199
};

1200
struct event_filter {
1201 1202
	int			n_preds;	/* Number assigned */
	int			a_preds;	/* allocated */
1203
	struct filter_pred	*preds;
1204
	struct filter_pred	*root;
1205
	char			*filter_string;
1206 1207
};

1208 1209 1210
struct event_subsystem {
	struct list_head	list;
	const char		*name;
1211
	struct event_filter	*filter;
1212
	int			ref_count;
1213 1214
};

1215
struct trace_subsystem_dir {
1216 1217 1218 1219 1220 1221 1222 1223
	struct list_head		list;
	struct event_subsystem		*subsystem;
	struct trace_array		*tr;
	struct dentry			*entry;
	int				ref_count;
	int				nr_events;
};

1224 1225 1226
extern int call_filter_check_discard(struct trace_event_call *call, void *rec,
				     struct ring_buffer *buffer,
				     struct ring_buffer_event *event);
1227 1228 1229 1230 1231 1232

void trace_buffer_unlock_commit_regs(struct trace_array *tr,
				     struct ring_buffer *buffer,
				     struct ring_buffer_event *event,
				     unsigned long flags, int pc,
				     struct pt_regs *regs);
1233 1234 1235 1236 1237 1238 1239 1240 1241

static inline void trace_buffer_unlock_commit(struct trace_array *tr,
					      struct ring_buffer *buffer,
					      struct ring_buffer_event *event,
					      unsigned long flags, int pc)
{
	trace_buffer_unlock_commit_regs(tr, buffer, event, flags, pc, NULL);
}

1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258
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 ring_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);
}

1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283
/*
 * Helper function for event_trigger_unlock_commit{_regs}().
 * If there are event triggers attached to this event that requires
 * filtering against its fields, then they wil be called as the
 * entry already holds the field information of the current event.
 *
 * It also checks if the event should be discarded or not.
 * It is to be discarded if the event is soft disabled and the
 * event was only recorded to process triggers, or if the event
 * filter is active and this event did not match the filters.
 *
 * Returns true if the event is discarded, false otherwise.
 */
static inline bool
__event_trigger_test_discard(struct trace_event_file *file,
			     struct ring_buffer *buffer,
			     struct ring_buffer_event *event,
			     void *entry,
			     enum event_trigger_type *tt)
{
	unsigned long eflags = file->flags;

	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
		*tt = event_triggers_call(file, entry);

1284 1285 1286
	if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) ||
	    (unlikely(file->flags & EVENT_FILE_FL_FILTERED) &&
	     !filter_match_preds(file->filter, entry))) {
1287
		__trace_event_discard_commit(buffer, event);
1288 1289
		return true;
	}
1290

1291
	return false;
1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354
}

/**
 * event_trigger_unlock_commit - handle triggers and finish event commit
 * @file: The file pointer assoctiated to the event
 * @buffer: The ring buffer that the event is being written to
 * @event: The event meta data in the ring buffer
 * @entry: The event itself
 * @irq_flags: The state of the interrupts at the start of the event
 * @pc: The state of the preempt count at the start of the event.
 *
 * This is a helper function to handle triggers that require data
 * from the event itself. It also tests the event against filters and
 * if the event is soft disabled and should be discarded.
 */
static inline void
event_trigger_unlock_commit(struct trace_event_file *file,
			    struct ring_buffer *buffer,
			    struct ring_buffer_event *event,
			    void *entry, unsigned long irq_flags, int pc)
{
	enum event_trigger_type tt = ETT_NONE;

	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
		trace_buffer_unlock_commit(file->tr, buffer, event, irq_flags, pc);

	if (tt)
		event_triggers_post_call(file, tt, entry);
}

/**
 * event_trigger_unlock_commit_regs - handle triggers and finish event commit
 * @file: The file pointer assoctiated to the event
 * @buffer: The ring buffer that the event is being written to
 * @event: The event meta data in the ring buffer
 * @entry: The event itself
 * @irq_flags: The state of the interrupts at the start of the event
 * @pc: The state of the preempt count at the start of the event.
 *
 * This is a helper function to handle triggers that require data
 * from the event itself. It also tests the event against filters and
 * if the event is soft disabled and should be discarded.
 *
 * Same as event_trigger_unlock_commit() but calls
 * trace_buffer_unlock_commit_regs() instead of trace_buffer_unlock_commit().
 */
static inline void
event_trigger_unlock_commit_regs(struct trace_event_file *file,
				 struct ring_buffer *buffer,
				 struct ring_buffer_event *event,
				 void *entry, unsigned long irq_flags, int pc,
				 struct pt_regs *regs)
{
	enum event_trigger_type tt = ETT_NONE;

	if (!__event_trigger_test_discard(file, buffer, event, entry, &tt))
		trace_buffer_unlock_commit_regs(file->tr, buffer, event,
						irq_flags, pc, regs);

	if (tt)
		event_triggers_post_call(file, tt, entry);
}

1355 1356
#define FILTER_PRED_INVALID	((unsigned short)-1)
#define FILTER_PRED_IS_RIGHT	(1 << 15)
1357
#define FILTER_PRED_FOLD	(1 << 15)
1358

1359 1360 1361 1362 1363 1364 1365 1366
/*
 * 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
1367

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Tom Zanussi 已提交
1368
struct filter_pred;
1369
struct regex;
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1370

1371
typedef int (*filter_pred_fn_t) (struct filter_pred *pred, void *event);
T
Tom Zanussi 已提交
1372

1373 1374
typedef int (*regex_match_func)(char *str, struct regex *r, int len);

1375
enum regex_type {
1376
	MATCH_FULL = 0,
1377 1378 1379
	MATCH_FRONT_ONLY,
	MATCH_MIDDLE_ONLY,
	MATCH_END_ONLY,
1380
	MATCH_GLOB,
1381 1382
};

1383 1384 1385 1386 1387 1388 1389
struct regex {
	char			pattern[MAX_FILTER_STR_VAL];
	int			len;
	int			field_len;
	regex_match_func	match;
};

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Tom Zanussi 已提交
1390
struct filter_pred {
1391 1392 1393
	filter_pred_fn_t 	fn;
	u64 			val;
	struct regex		regex;
1394
	unsigned short		*ops;
1395
	struct ftrace_event_field *field;
1396 1397 1398
	int 			offset;
	int 			not;
	int 			op;
1399 1400 1401 1402
	unsigned short		index;
	unsigned short		parent;
	unsigned short		left;
	unsigned short		right;
T
Tom Zanussi 已提交
1403 1404
};

1405 1406 1407 1408
static inline bool is_string_field(struct ftrace_event_field *field)
{
	return field->filter_type == FILTER_DYN_STRING ||
	       field->filter_type == FILTER_STATIC_STRING ||
1409 1410
	       field->filter_type == FILTER_PTR_STRING ||
	       field->filter_type == FILTER_COMM;
1411 1412 1413 1414 1415 1416 1417
}

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

1418 1419
extern enum regex_type
filter_parse_regex(char *buff, int len, char **search, int *not);
1420
extern void print_event_filter(struct trace_event_file *file,
1421
			       struct trace_seq *s);
1422
extern int apply_event_filter(struct trace_event_file *file,
1423
			      char *filter_string);
1424
extern int apply_subsystem_event_filter(struct trace_subsystem_dir *dir,
1425 1426
					char *filter_string);
extern void print_subsystem_event_filter(struct event_subsystem *system,
1427
					 struct trace_seq *s);
1428
extern int filter_assign_type(const char *type);
1429
extern int create_event_filter(struct trace_event_call *call,
1430 1431 1432
			       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
1433

1434
struct ftrace_event_field *
1435
trace_find_event_field(struct trace_event_call *call, char *name);
1436

1437
extern void trace_event_enable_cmd_record(bool enable);
1438
extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr);
1439
extern int event_trace_del_tracer(struct trace_array *tr);
1440

1441 1442 1443
extern struct trace_event_file *find_event_file(struct trace_array *tr,
						const char *system,
						const char *event);
1444

1445 1446 1447 1448 1449
static inline void *event_file_data(struct file *filp)
{
	return ACCESS_ONCE(file_inode(filp)->i_private);
}

1450
extern struct mutex event_mutex;
1451
extern struct list_head ftrace_events;
P
Peter Zijlstra 已提交
1452

1453
extern const struct file_operations event_trigger_fops;
1454 1455 1456 1457
extern const struct file_operations event_hist_fops;

#ifdef CONFIG_HIST_TRIGGERS
extern int register_trigger_hist_cmd(void);
1458
extern int register_trigger_hist_enable_disable_cmds(void);
1459 1460
#else
static inline int register_trigger_hist_cmd(void) { return 0; }
1461
static inline int register_trigger_hist_enable_disable_cmds(void) { return 0; }
1462
#endif
1463 1464 1465 1466 1467 1468 1469 1470 1471

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;
1472
	struct event_filter __rcu	*filter;
1473 1474
	char				*filter_str;
	void				*private_data;
1475
	bool				paused;
1476
	bool				paused_tmp;
1477
	struct list_head		list;
1478 1479 1480
	char				*name;
	struct list_head		named_list;
	struct event_trigger_data	*named_data;
1481 1482
};

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/* Avoid typos */
#define ENABLE_EVENT_STR	"enable_event"
#define DISABLE_EVENT_STR	"disable_event"
#define ENABLE_HIST_STR		"enable_hist"
#define DISABLE_HIST_STR	"disable_hist"

struct enable_trigger_data {
	struct trace_event_file		*file;
	bool				enable;
	bool				hist;
};

extern int event_enable_trigger_print(struct seq_file *m,
				      struct event_trigger_ops *ops,
				      struct event_trigger_data *data);
extern void event_enable_trigger_free(struct event_trigger_ops *ops,
				      struct event_trigger_data *data);
extern int event_enable_trigger_func(struct event_command *cmd_ops,
				     struct trace_event_file *file,
				     char *glob, char *cmd, char *param);
extern int event_enable_register_trigger(char *glob,
					 struct event_trigger_ops *ops,
					 struct event_trigger_data *data,
					 struct trace_event_file *file);
extern void event_enable_unregister_trigger(char *glob,
					    struct event_trigger_ops *ops,
					    struct event_trigger_data *test,
					    struct trace_event_file *file);
1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522
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);
1523 1524 1525 1526 1527 1528 1529 1530 1531
extern struct event_trigger_data *find_named_trigger(const char *name);
extern bool is_named_trigger(struct event_trigger_data *test);
extern int save_named_trigger(const char *name,
			      struct event_trigger_data *data);
extern void del_named_trigger(struct event_trigger_data *data);
extern void pause_named_trigger(struct event_trigger_data *data);
extern void unpause_named_trigger(struct event_trigger_data *data);
extern void set_named_trigger_data(struct event_trigger_data *data,
				   struct event_trigger_data *named_data);
1532
extern int register_event_command(struct event_command *cmd);
1533 1534
extern int unregister_event_command(struct event_command *cmd);
extern int register_trigger_hist_enable_disable_cmds(void);
1535

1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547
/**
 * 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
1548 1549
 *	registered the trigger (see struct event_command) along with
 *	the trace record, rec.
1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573
 *
 * @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 {
1574 1575
	void			(*func)(struct event_trigger_data *data,
					void *rec);
1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616
	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
1617
 *	enum in include/linux/trace_events.h.
1618
 *
1619
 * @flags: See the enum event_command_flags below.
1620
 *
1621 1622
 * All the methods below, except for @set_filter() and @unreg_all(),
 * must be implemented.
1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646
 *
 * @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).
 *
1647 1648 1649 1650
 * @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.
 *
1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663
 * @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;
1664
	int			flags;
1665
	int			(*func)(struct event_command *cmd_ops,
1666
					struct trace_event_file *file,
1667 1668 1669 1670
					char *glob, char *cmd, char *params);
	int			(*reg)(char *glob,
				       struct event_trigger_ops *ops,
				       struct event_trigger_data *data,
1671
				       struct trace_event_file *file);
1672 1673 1674
	void			(*unreg)(char *glob,
					 struct event_trigger_ops *ops,
					 struct event_trigger_data *data,
1675
					 struct trace_event_file *file);
1676
	void			(*unreg_all)(struct trace_event_file *file);
1677 1678
	int			(*set_filter)(char *filter_str,
					      struct event_trigger_data *data,
1679
					      struct trace_event_file *file);
1680 1681 1682
	struct event_trigger_ops *(*get_trigger_ops)(char *cmd, char *param);
};

1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725
/**
 * 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;
}

1726
extern int trace_event_enable_disable(struct trace_event_file *file,
1727
				      int enable, int soft_disable);
1728
extern int tracing_alloc_snapshot(void);
1729

1730 1731 1732
extern const char *__start___trace_bprintk_fmt[];
extern const char *__stop___trace_bprintk_fmt[];

1733 1734 1735
extern const char *__start___tracepoint_str[];
extern const char *__stop___tracepoint_str[];

1736
void trace_printk_control(bool enabled);
1737
void trace_printk_init_buffers(void);
1738
void trace_printk_start_comm(void);
1739
int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set);
1740
int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled);
1741

1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752
/*
 * 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))

1753
#undef FTRACE_ENTRY
1754
#define FTRACE_ENTRY(call, struct_name, id, tstruct, print, filter)	\
1755
	extern struct trace_event_call					\
1756
	__aligned(4) event_##call;
1757
#undef FTRACE_ENTRY_DUP
1758 1759 1760
#define FTRACE_ENTRY_DUP(call, struct_name, id, tstruct, print, filter)	\
	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
		     filter)
1761 1762 1763 1764 1765
#undef FTRACE_ENTRY_PACKED
#define FTRACE_ENTRY_PACKED(call, struct_name, id, tstruct, print, filter) \
	FTRACE_ENTRY(call, struct_name, id, PARAMS(tstruct), PARAMS(print), \
		     filter)

1766
#include "trace_entries.h"
1767

1768
#if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_FUNCTION_TRACER)
1769
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
1773
#endif
1774

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#ifdef CONFIG_FTRACE_SYSCALLS
void init_ftrace_syscalls(void);
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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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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_eval_update(struct trace_eval_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_eval_update(struct trace_eval_map **map, int len) { }
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#endif

1794
extern struct trace_iterator *tracepoint_print_iter;
1795

1796
#endif /* _LINUX_KERNEL_TRACE_H */