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