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 */
ftrace_event_register(struct trace_event_call * call,enum trace_reg type,void * data)18 static 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 __array_desc
55 #define __array_desc(type, container, item, size) type item[size];
56
57 #undef __dynamic_array
58 #define __dynamic_array(type, item) type item[];
59
60 #undef F_STRUCT
61 #define F_STRUCT(args...) args
62
63 #undef F_printk
64 #define F_printk(fmt, args...) fmt, args
65
66 #undef FTRACE_ENTRY
67 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \
68 struct ____ftrace_##name { \
69 tstruct \
70 }; \
71 static void __always_unused ____ftrace_check_##name(void) \
72 { \
73 struct ____ftrace_##name *__entry = NULL; \
74 \
75 /* force compile-time check on F_printk() */ \
76 printk(print); \
77 }
78
79 #undef FTRACE_ENTRY_DUP
80 #define FTRACE_ENTRY_DUP(name, struct_name, id, tstruct, print) \
81 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print))
82
83 #include "trace_entries.h"
84
85 #undef __field_ext
86 #define __field_ext(_type, _item, _filter_type) { \
87 .type = #_type, .name = #_item, \
88 .size = sizeof(_type), .align = __alignof__(_type), \
89 is_signed_type(_type), .filter_type = _filter_type },
90
91
92 #undef __field_ext_packed
93 #define __field_ext_packed(_type, _item, _filter_type) { \
94 .type = #_type, .name = #_item, \
95 .size = sizeof(_type), .align = 1, \
96 is_signed_type(_type), .filter_type = _filter_type },
97
98 #undef __field
99 #define __field(_type, _item) __field_ext(_type, _item, FILTER_OTHER)
100
101 #undef __field_fn
102 #define __field_fn(_type, _item) __field_ext(_type, _item, FILTER_TRACE_FN)
103
104 #undef __field_desc
105 #define __field_desc(_type, _container, _item) __field_ext(_type, _item, FILTER_OTHER)
106
107 #undef __field_packed
108 #define __field_packed(_type, _container, _item) __field_ext_packed(_type, _item, FILTER_OTHER)
109
110 #undef __array
111 #define __array(_type, _item, _len) { \
112 .type = #_type"["__stringify(_len)"]", .name = #_item, \
113 .size = sizeof(_type[_len]), .align = __alignof__(_type), \
114 is_signed_type(_type), .filter_type = FILTER_OTHER },
115
116 #undef __array_desc
117 #define __array_desc(_type, _container, _item, _len) __array(_type, _item, _len)
118
119 #undef __dynamic_array
120 #define __dynamic_array(_type, _item) { \
121 .type = #_type "[]", .name = #_item, \
122 .size = 0, .align = __alignof__(_type), \
123 is_signed_type(_type), .filter_type = FILTER_OTHER },
124
125 #undef FTRACE_ENTRY
126 #define FTRACE_ENTRY(name, struct_name, id, tstruct, print) \
127 static struct trace_event_fields ftrace_event_fields_##name[] = { \
128 tstruct \
129 {} };
130
131 #include "trace_entries.h"
132
133 #undef __entry
134 #define __entry REC
135
136 #undef __field
137 #define __field(type, item)
138
139 #undef __field_fn
140 #define __field_fn(type, item)
141
142 #undef __field_desc
143 #define __field_desc(type, container, item)
144
145 #undef __field_packed
146 #define __field_packed(type, container, item)
147
148 #undef __array
149 #define __array(type, item, len)
150
151 #undef __array_desc
152 #define __array_desc(type, container, item, len)
153
154 #undef __dynamic_array
155 #define __dynamic_array(type, item)
156
157 #undef F_printk
158 #define F_printk(fmt, args...) __stringify(fmt) ", " __stringify(args)
159
160 #undef FTRACE_ENTRY_REG
161 #define FTRACE_ENTRY_REG(call, struct_name, etype, tstruct, print, regfn) \
162 static struct trace_event_class __refdata event_class_ftrace_##call = { \
163 .system = __stringify(TRACE_SYSTEM), \
164 .fields_array = ftrace_event_fields_##call, \
165 .fields = LIST_HEAD_INIT(event_class_ftrace_##call.fields),\
166 .reg = regfn, \
167 }; \
168 \
169 struct trace_event_call __used event_##call = { \
170 .class = &event_class_ftrace_##call, \
171 { \
172 .name = #call, \
173 }, \
174 .event.type = etype, \
175 .print_fmt = print, \
176 .flags = TRACE_EVENT_FL_IGNORE_ENABLE, \
177 }; \
178 static struct trace_event_call __used \
179 __section("_ftrace_events") *__event_##call = &event_##call;
180
181 #undef FTRACE_ENTRY
182 #define FTRACE_ENTRY(call, struct_name, etype, tstruct, print) \
183 FTRACE_ENTRY_REG(call, struct_name, etype, \
184 PARAMS(tstruct), PARAMS(print), NULL)
185
ftrace_event_is_function(struct trace_event_call * call)186 bool ftrace_event_is_function(struct trace_event_call *call)
187 {
188 return call == &event_function;
189 }
190
191 #include "trace_entries.h"
192