1// SPDX-License-Identifier: GPL-2.0
2/*
3 * trace_export.c - export basic ftrace utilities to user space
4 *
5 * Copyright (C) 2009 Steven Rostedt <srostedt@redhat.com>
6 */
7#include <linux/stringify.h>
8#include <linux/kallsyms.h>
9#include <linux/seq_file.h>
10#include <linux/uaccess.h>
11#include <linux/ftrace.h>
12#include <linux/module.h>
13#include <linux/init.h>
14
15#include "trace_output.h"
16
17/* Stub function for events with triggers */
18static int ftrace_event_register(struct trace_event_call *call,
19				 enum trace_reg type, void *data)
20{
21	return 0;
22}
23
24#undef TRACE_SYSTEM
25#define TRACE_SYSTEM	ftrace
26
27/*
28 * The FTRACE_ENTRY_REG macro allows ftrace entry to define register
29 * function and thus become accessible via perf.
30 */
31#undef FTRACE_ENTRY_REG
32#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, regfn) \
33	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
34
35/* not needed for this file */
36#undef __field_struct
37#define __field_struct(type, item)
38
39#undef __field
40#define __field(type, item)				type item;
41
42#undef __field_fn
43#define __field_fn(type, item)				type item;
44
45#undef __field_desc
46#define __field_desc(type, container, item)		type item;
47
48#undef __field_packed
49#define __field_packed(type, container, item)		type item;
50
51#undef __array
52#define __array(type, item, size)			type item[size];
53
54#undef __stack_array
55#define __stack_array(type, item, size, field)		__array(type, item, size)
56
57#undef __array_desc
58#define __array_desc(type, container, item, size)	type item[size];
59
60#undef __dynamic_array
61#define __dynamic_array(type, item)			type item[];
62
63#undef F_STRUCT
64#define F_STRUCT(args...)				args
65
66#undef F_printk
67#define F_printk(fmt, args...) fmt, args
68
69#undef FTRACE_ENTRY
70#define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
71struct ____ftrace_##name {						\
72	tstruct								\
73};									\
74static void __always_unused ____ftrace_check_##name(void)		\
75{									\
76	struct ____ftrace_##name *__entry = NULL;			\
77									\
78	/* force compile-time check on F_printk() */			\
79	printk(print);							\
80}
81
82#undef FTRACE_ENTRY_DUP
83#define FTRACE_ENTRY_DUP(name, struct_name, id, tstruct, print)		\
84	FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
85
86#include "trace_entries.h"
87
88#undef __field_ext
89#define __field_ext(_type, _item, _filter_type) {			\
90	.type = #_type, .name = #_item,					\
91	.size = sizeof(_type), .align = __alignof__(_type),		\
92	is_signed_type(_type), .filter_type = _filter_type },
93
94
95#undef __field_ext_packed
96#define __field_ext_packed(_type, _item, _filter_type) {	\
97	.type = #_type, .name = #_item,				\
98	.size = sizeof(_type), .align = 1,			\
99	is_signed_type(_type), .filter_type = _filter_type },
100
101#undef __field
102#define __field(_type, _item) __field_ext(_type, _item, FILTER_OTHER)
103
104#undef __field_fn
105#define __field_fn(_type, _item) __field_ext(_type, _item, FILTER_TRACE_FN)
106
107#undef __field_desc
108#define __field_desc(_type, _container, _item) __field_ext(_type, _item, FILTER_OTHER)
109
110#undef __field_packed
111#define __field_packed(_type, _container, _item) __field_ext_packed(_type, _item, FILTER_OTHER)
112
113#undef __array
114#define __array(_type, _item, _len) {					\
115	.type = #_type"["__stringify(_len)"]", .name = #_item,		\
116	.size = sizeof(_type[_len]), .align = __alignof__(_type),	\
117	is_signed_type(_type), .filter_type = FILTER_OTHER,			\
118	.len = _len },
119
120#undef __stack_array
121#define __stack_array(_type, _item, _len, _field) __array(_type, _item, _len)
122
123#undef __array_desc
124#define __array_desc(_type, _container, _item, _len) __array(_type, _item, _len)
125
126#undef __dynamic_array
127#define __dynamic_array(_type, _item) {					\
128	.type = #_type "[]", .name = #_item,				\
129	.size = 0, .align = __alignof__(_type),				\
130	is_signed_type(_type), .filter_type = FILTER_OTHER },
131
132#undef FTRACE_ENTRY
133#define FTRACE_ENTRY(name, struct_name, id, tstruct, print)		\
134static struct trace_event_fields ftrace_event_fields_##name[] = {	\
135	tstruct								\
136	{} };
137
138#include "trace_entries.h"
139
140#undef __entry
141#define __entry REC
142
143#undef __field
144#define __field(type, item)
145
146#undef __field_fn
147#define __field_fn(type, item)
148
149#undef __field_desc
150#define __field_desc(type, container, item)
151
152#undef __field_packed
153#define __field_packed(type, container, item)
154
155#undef __array
156#define __array(type, item, len)
157
158#undef __stack_array
159#define __stack_array(type, item, len, field)
160
161#undef __array_desc
162#define __array_desc(type, container, item, len)
163
164#undef __dynamic_array
165#define __dynamic_array(type, item)
166
167#undef F_printk
168#define F_printk(fmt, args...) __stringify(fmt) ", "  __stringify(args)
169
170#undef FTRACE_ENTRY_REG
171#define FTRACE_ENTRY_REG(call, struct_name, etype, tstruct, print, regfn) \
172static struct trace_event_class __refdata event_class_ftrace_##call = {	\
173	.system			= __stringify(TRACE_SYSTEM),		\
174	.fields_array		= ftrace_event_fields_##call,		\
175	.fields			= LIST_HEAD_INIT(event_class_ftrace_##call.fields),\
176	.reg			= regfn,				\
177};									\
178									\
179struct trace_event_call __used event_##call = {				\
180	.class			= &event_class_ftrace_##call,		\
181	{								\
182		.name			= #call,			\
183	},								\
184	.event.type		= etype,				\
185	.print_fmt		= print,				\
186	.flags			= TRACE_EVENT_FL_IGNORE_ENABLE,		\
187};									\
188static struct trace_event_call __used						\
189__section("_ftrace_events") *__event_##call = &event_##call;
190
191#undef FTRACE_ENTRY
192#define FTRACE_ENTRY(call, struct_name, etype, tstruct, print)		\
193	FTRACE_ENTRY_REG(call, struct_name, etype,			\
194			 PARAMS(tstruct), PARAMS(print), NULL)
195
196bool ftrace_event_is_function(struct trace_event_call *call)
197{
198	return call == &event_function;
199}
200
201#include "trace_entries.h"
202