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 accesible via perf.
30 */
31#undef FTRACE_ENTRY_REG
32#define FTRACE_ENTRY_REG(name, struct_name, id, tstruct, print, \
33 filter, regfn) \
34 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
35 filter)
36
37/* not needed for this file */
38#undef __field_struct
39#define __field_struct(type, item)
40
41#undef __field
42#define __field(type, item) type item;
43
44#undef __field_desc
45#define __field_desc(type, container, item) type item;
46
47#undef __array
48#define __array(type, item, size) type item[size];
49
50#undef __array_desc
51#define __array_desc(type, container, item, size) type item[size];
52
53#undef __dynamic_array
54#define __dynamic_array(type, item) type item[];
55
56#undef F_STRUCT
57#define F_STRUCT(args...) args
58
59#undef F_printk
60#define F_printk(fmt, args...) fmt, args
61
62#undef FTRACE_ENTRY
63#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \
64struct ____ftrace_##name { \
65 tstruct \
66}; \
67static void __always_unused ____ftrace_check_##name(void) \
68{ \
69 struct ____ftrace_##name *__entry = NULL; \
70 \
71 /* force compile-time check on F_printk() */ \
72 printk(print); \
73}
74
75#undef FTRACE_ENTRY_DUP
76#define FTRACE_ENTRY_DUP(name, struct_name, id, tstruct, print, filter) \
77 FTRACE_ENTRY(name, struct_name, id, PARAMS(tstruct), PARAMS(print), \
78 filter)
79
80#include "trace_entries.h"
81
82#undef __field
83#define __field(type, item) \
84 ret = trace_define_field(event_call, #type, #item, \
85 offsetof(typeof(field), item), \
86 sizeof(field.item), \
87 is_signed_type(type), filter_type); \
88 if (ret) \
89 return ret;
90
91#undef __field_desc
92#define __field_desc(type, container, item) \
93 ret = trace_define_field(event_call, #type, #item, \
94 offsetof(typeof(field), \
95 container.item), \
96 sizeof(field.container.item), \
97 is_signed_type(type), filter_type); \
98 if (ret) \
99 return ret;
100
101#undef __array
102#define __array(type, item, len) \
103 do { \
104 char *type_str = #type"["__stringify(len)"]"; \
105 BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \
106 ret = trace_define_field(event_call, type_str, #item, \
107 offsetof(typeof(field), item), \
108 sizeof(field.item), \
109 is_signed_type(type), filter_type); \
110 if (ret) \
111 return ret; \
112 } while (0);
113
114#undef __array_desc
115#define __array_desc(type, container, item, len) \
116 BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \
117 ret = trace_define_field(event_call, #type "[" #len "]", #item, \
118 offsetof(typeof(field), \
119 container.item), \
120 sizeof(field.container.item), \
121 is_signed_type(type), filter_type); \
122 if (ret) \
123 return ret;
124
125#undef __dynamic_array
126#define __dynamic_array(type, item) \
127 ret = trace_define_field(event_call, #type "[]", #item, \
128 offsetof(typeof(field), item), \
129 0, is_signed_type(type), filter_type);\
130 if (ret) \
131 return ret;
132
133#undef FTRACE_ENTRY
134#define FTRACE_ENTRY(name, struct_name, id, tstruct, print, filter) \
135static int __init \
136ftrace_define_fields_##name(struct trace_event_call *event_call) \
137{ \
138 struct struct_name field; \
139 int ret; \
140 int filter_type = filter; \
141 \
142 tstruct; \
143 \
144 return ret; \
145}
146
147#include "trace_entries.h"
148
149#undef __entry
150#define __entry REC
151
152#undef __field
153#define __field(type, item)
154
155#undef __field_desc
156#define __field_desc(type, container, item)
157
158#undef __array
159#define __array(type, item, len)
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, filter,\
172 regfn) \
173 \
174struct trace_event_class __refdata event_class_ftrace_##call = { \
175 .system = __stringify(TRACE_SYSTEM), \
176 .define_fields = ftrace_define_fields_##call, \
177 .fields = LIST_HEAD_INIT(event_class_ftrace_##call.fields),\
178 .reg = regfn, \
179}; \
180 \
181struct trace_event_call __used event_##call = { \
182 .class = &event_class_ftrace_##call, \
183 { \
184 .name = #call, \
185 }, \
186 .event.type = etype, \
187 .print_fmt = print, \
188 .flags = TRACE_EVENT_FL_IGNORE_ENABLE, \
189}; \
190struct trace_event_call __used \
191__attribute__((section("_ftrace_events"))) *__event_##call = &event_##call;
192
193#undef FTRACE_ENTRY
194#define FTRACE_ENTRY(call, struct_name, etype, tstruct, print, filter) \
195 FTRACE_ENTRY_REG(call, struct_name, etype, \
196 PARAMS(tstruct), PARAMS(print), filter, NULL)
197
198bool ftrace_event_is_function(struct trace_event_call *call)
199{
200 return call == &event_function;
201}
202
203#include "trace_entries.h"
204