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 __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) \
71 struct ____ftrace_##name { \
72 tstruct \
73 }; \
74 static 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) \
134 static 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) \
172 static 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 \
179 struct 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 }; \
188 static 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
ftrace_event_is_function(struct trace_event_call * call)196 bool ftrace_event_is_function(struct trace_event_call *call)
197 {
198 return call == &event_function;
199 }
200
201 #include "trace_entries.h"
202