1/*
2 * trace_export.c - export basic ftrace utilities to user space
3 *
4 * Copyright (C) 2009 Steven Rostedt <srostedt@redhat.com>
5 */
6#include <linux/stringify.h>
7#include <linux/kallsyms.h>
8#include <linux/seq_file.h>
9#include <linux/uaccess.h>
10#include <linux/ftrace.h>
11#include <linux/module.h>
12#include <linux/init.h>
13
14#include "trace_output.h"
15
16#undef TRACE_SYSTEM
17#define TRACE_SYSTEM	ftrace
18
19/*
20 * The FTRACE_ENTRY_REG macro allows ftrace entry to define register
21 * function and thus become accesible via perf.
22 */
23#undef FTRACE_ENTRY_REG
24#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \
25			 filter, regfn) \
26	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
27		     filter)
28
29/* not needed for this file */
30#undef __field_struct
31#define __field_struct(type, item)
32
33#undef __field
34#define __field(type, item)				type item;
35
36#undef __field_desc
37#define __field_desc(type, container, item)		type item;
38
39#undef __array
40#define __array(type, item, size)			type item[size];
41
42#undef __array_desc
43#define __array_desc(type, container, item, size)	type item[size];
44
45#undef __dynamic_array
46#define __dynamic_array(type, item)			type item[];
47
48#undef F_STRUCT
49#define F_STRUCT(args...)				args
50
51#undef F_printk
52#define F_printk(fmt, args...) fmt, args
53
54#undef FTRACE_ENTRY
55#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter)	\
56struct ____ftrace_##name {						\
57	tstruct								\
58};									\
59static void __always_unused ____ftrace_check_##name(void)		\
60{									\
61	struct ____ftrace_##name *__entry = NULL;			\
62									\
63	/* force compile-time check on F_printk() */			\
64	printk(print);							\
65}
66
67#undef FTRACE_ENTRY_DUP
68#define FTRACE_ENTRY_DUP(name, struct_name, id, tstruct, print, filter)	\
69	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
70		     filter)
71
72#include "trace_entries.h"
73
74#undef __field
75#define __field(type, item)						\
76	ret = trace_define_field(event_call, #type, #item,		\
77				 offsetof(typeof(field), item),		\
78				 sizeof(field.item),			\
79				 is_signed_type(type), filter_type);	\
80	if (ret)							\
81		return ret;
82
83#undef __field_desc
84#define __field_desc(type, container, item)	\
85	ret = trace_define_field(event_call, #type, #item,		\
86				 offsetof(typeof(field),		\
87					  container.item),		\
88				 sizeof(field.container.item),		\
89				 is_signed_type(type), filter_type);	\
90	if (ret)							\
91		return ret;
92
93#undef __array
94#define __array(type, item, len)					\
95	do {								\
96		char *type_str = #type"["__stringify(len)"]";		\
97		BUILD_BUG_ON(len > MAX_FILTER_STR_VAL);			\
98		ret = trace_define_field(event_call, type_str, #item,	\
99				 offsetof(typeof(field), item),		\
100				 sizeof(field.item),			\
101				 is_signed_type(type), filter_type);	\
102		if (ret)						\
103			return ret;					\
104	} while (0);
105
106#undef __array_desc
107#define __array_desc(type, container, item, len)			\
108	BUILD_BUG_ON(len > MAX_FILTER_STR_VAL);				\
109	ret = trace_define_field(event_call, #type "[" #len "]", #item,	\
110				 offsetof(typeof(field),		\
111					  container.item),		\
112				 sizeof(field.container.item),		\
113				 is_signed_type(type), filter_type);	\
114	if (ret)							\
115		return ret;
116
117#undef __dynamic_array
118#define __dynamic_array(type, item)					\
119	ret = trace_define_field(event_call, #type, #item,		\
120				 offsetof(typeof(field), item),		\
121				 0, is_signed_type(type), filter_type);\
122	if (ret)							\
123		return ret;
124
125#undef FTRACE_ENTRY
126#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter)	\
127static int __init							\
128ftrace_define_fields_##name(struct ftrace_event_call *event_call)	\
129{									\
130	struct struct_name field;					\
131	int ret;							\
132	int filter_type = filter;					\
133									\
134	tstruct;							\
135									\
136	return ret;							\
137}
138
139#include "trace_entries.h"
140
141#undef __entry
142#define __entry REC
143
144#undef __field
145#define __field(type, item)
146
147#undef __field_desc
148#define __field_desc(type, container, item)
149
150#undef __array
151#define __array(type, item, len)
152
153#undef __array_desc
154#define __array_desc(type, container, item, len)
155
156#undef __dynamic_array
157#define __dynamic_array(type, item)
158
159#undef F_printk
160#define F_printk(fmt, args...) __stringify(fmt) ", "  __stringify(args)
161
162#undef FTRACE_ENTRY_REG
163#define FTRACE_ENTRY_REG(call, struct_name, etype, tstruct, print, filter,\
164			 regfn)						\
165									\
166struct ftrace_event_class __refdata event_class_ftrace_##call = {	\
167	.system			= __stringify(TRACE_SYSTEM),		\
168	.define_fields		= ftrace_define_fields_##call,		\
169	.fields			= LIST_HEAD_INIT(event_class_ftrace_##call.fields),\
170	.reg			= regfn,				\
171};									\
172									\
173struct ftrace_event_call __used event_##call = {			\
174	.class			= &event_class_ftrace_##call,		\
175	{								\
176		.name			= #call,			\
177	},								\
178	.event.type		= etype,				\
179	.print_fmt		= print,				\
180	.flags			= TRACE_EVENT_FL_IGNORE_ENABLE,		\
181};									\
182struct ftrace_event_call __used						\
183__attribute__((section("_ftrace_events"))) *__event_##call = &event_##call;
184
185#undef FTRACE_ENTRY
186#define FTRACE_ENTRY(call, struct_name, etype, tstruct, print, filter)	\
187	FTRACE_ENTRY_REG(call, struct_name, etype,			\
188			 PARAMS(tstruct), PARAMS(print), filter, NULL)
189
190int ftrace_event_is_function(struct ftrace_event_call *call)
191{
192	return call == &event_function;
193}
194
195#include "trace_entries.h"
196