xref: /openbmc/linux/kernel/trace/trace_export.c (revision 78c99ba1)
1 /*
2  * trace_export.c - export basic ftrace utilities to user space
3  *
4  * Copyright (C) 2009 Steven Rostedt <srostedt@redhat.com>
5  */
6 #include <linux/stringify.h>
7 #include <linux/kallsyms.h>
8 #include <linux/seq_file.h>
9 #include <linux/debugfs.h>
10 #include <linux/uaccess.h>
11 #include <linux/ftrace.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/fs.h>
15 
16 #include "trace_output.h"
17 
18 
19 #undef TRACE_STRUCT
20 #define TRACE_STRUCT(args...) args
21 
22 extern void __bad_type_size(void);
23 
24 #undef TRACE_FIELD
25 #define TRACE_FIELD(type, item, assign)					\
26 	if (sizeof(type) != sizeof(field.item))				\
27 		__bad_type_size();					\
28 	ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"	\
29 			       "offset:%u;\tsize:%u;\n",		\
30 			       (unsigned int)offsetof(typeof(field), item), \
31 			       (unsigned int)sizeof(field.item));	\
32 	if (!ret)							\
33 		return 0;
34 
35 
36 #undef TRACE_FIELD_SPECIAL
37 #define TRACE_FIELD_SPECIAL(type_item, item, len, cmd)			\
38 	ret = trace_seq_printf(s, "\tfield special:" #type_item ";\t"	\
39 			       "offset:%u;\tsize:%u;\n",		\
40 			       (unsigned int)offsetof(typeof(field), item), \
41 			       (unsigned int)sizeof(field.item));	\
42 	if (!ret)							\
43 		return 0;
44 
45 #undef TRACE_FIELD_ZERO_CHAR
46 #define TRACE_FIELD_ZERO_CHAR(item)					\
47 	ret = trace_seq_printf(s, "\tfield:char " #item ";\t"		\
48 			       "offset:%u;\tsize:0;\n",			\
49 			       (unsigned int)offsetof(typeof(field), item)); \
50 	if (!ret)							\
51 		return 0;
52 
53 #undef TRACE_FIELD_SIGN
54 #define TRACE_FIELD_SIGN(type, item, assign, is_signed)	\
55 	TRACE_FIELD(type, item, assign)
56 
57 #undef TP_RAW_FMT
58 #define TP_RAW_FMT(args...) args
59 
60 #undef TRACE_EVENT_FORMAT
61 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)	\
62 static int								\
63 ftrace_format_##call(struct trace_seq *s)				\
64 {									\
65 	struct args field;						\
66 	int ret;							\
67 									\
68 	tstruct;							\
69 									\
70 	trace_seq_printf(s, "\nprint fmt: \"%s\"\n", tpfmt);		\
71 									\
72 	return ret;							\
73 }
74 
75 #undef TRACE_EVENT_FORMAT_NOFILTER
76 #define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct,	\
77 				    tpfmt)				\
78 static int								\
79 ftrace_format_##call(struct trace_seq *s)				\
80 {									\
81 	struct args field;						\
82 	int ret;							\
83 									\
84 	tstruct;							\
85 									\
86 	trace_seq_printf(s, "\nprint fmt: \"%s\"\n", tpfmt);		\
87 									\
88 	return ret;							\
89 }
90 
91 #include "trace_event_types.h"
92 
93 #undef TRACE_ZERO_CHAR
94 #define TRACE_ZERO_CHAR(arg)
95 
96 #undef TRACE_FIELD
97 #define TRACE_FIELD(type, item, assign)\
98 	entry->item = assign;
99 
100 #undef TRACE_FIELD
101 #define TRACE_FIELD(type, item, assign)\
102 	entry->item = assign;
103 
104 #undef TRACE_FIELD_SIGN
105 #define TRACE_FIELD_SIGN(type, item, assign, is_signed)	\
106 	TRACE_FIELD(type, item, assign)
107 
108 #undef TP_CMD
109 #define TP_CMD(cmd...)	cmd
110 
111 #undef TRACE_ENTRY
112 #define TRACE_ENTRY	entry
113 
114 #undef TRACE_FIELD_SPECIAL
115 #define TRACE_FIELD_SPECIAL(type_item, item, len, cmd)	\
116 	cmd;
117 
118 #undef TRACE_EVENT_FORMAT
119 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)	\
120 int ftrace_define_fields_##call(void);					\
121 static int ftrace_raw_init_event_##call(void);				\
122 									\
123 struct ftrace_event_call __used						\
124 __attribute__((__aligned__(4)))						\
125 __attribute__((section("_ftrace_events"))) event_##call = {		\
126 	.name			= #call,				\
127 	.id			= proto,				\
128 	.system			= __stringify(TRACE_SYSTEM),		\
129 	.raw_init		= ftrace_raw_init_event_##call,		\
130 	.show_format		= ftrace_format_##call,			\
131 	.define_fields		= ftrace_define_fields_##call,		\
132 };									\
133 static int ftrace_raw_init_event_##call(void)				\
134 {									\
135 	INIT_LIST_HEAD(&event_##call.fields);				\
136 	init_preds(&event_##call);					\
137 	return 0;							\
138 }									\
139 
140 #undef TRACE_EVENT_FORMAT_NOFILTER
141 #define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct,	\
142 				    tpfmt)				\
143 									\
144 struct ftrace_event_call __used						\
145 __attribute__((__aligned__(4)))						\
146 __attribute__((section("_ftrace_events"))) event_##call = {		\
147 	.name			= #call,				\
148 	.id			= proto,				\
149 	.system			= __stringify(TRACE_SYSTEM),		\
150 	.show_format		= ftrace_format_##call,			\
151 };
152 
153 #include "trace_event_types.h"
154 
155 #undef TRACE_FIELD
156 #define TRACE_FIELD(type, item, assign)					\
157 	ret = trace_define_field(event_call, #type, #item,		\
158 				 offsetof(typeof(field), item),		\
159 				 sizeof(field.item), is_signed_type(type));	\
160 	if (ret)							\
161 		return ret;
162 
163 #undef TRACE_FIELD_SPECIAL
164 #define TRACE_FIELD_SPECIAL(type, item, len, cmd)			\
165 	ret = trace_define_field(event_call, #type "[" #len "]", #item,	\
166 				 offsetof(typeof(field), item),		\
167 				 sizeof(field.item), 0);		\
168 	if (ret)							\
169 		return ret;
170 
171 #undef TRACE_FIELD_SIGN
172 #define TRACE_FIELD_SIGN(type, item, assign, is_signed)			\
173 	ret = trace_define_field(event_call, #type, #item,		\
174 				 offsetof(typeof(field), item),		\
175 				 sizeof(field.item), is_signed);	\
176 	if (ret)							\
177 		return ret;
178 
179 #undef TRACE_FIELD_ZERO_CHAR
180 #define TRACE_FIELD_ZERO_CHAR(item)
181 
182 #undef TRACE_EVENT_FORMAT
183 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)	\
184 int									\
185 ftrace_define_fields_##call(void)					\
186 {									\
187 	struct ftrace_event_call *event_call = &event_##call;		\
188 	struct args field;						\
189 	int ret;							\
190 									\
191 	__common_field(unsigned char, type, 0);				\
192 	__common_field(unsigned char, flags, 0);			\
193 	__common_field(unsigned char, preempt_count, 0);		\
194 	__common_field(int, pid, 1);					\
195 	__common_field(int, tgid, 1);					\
196 									\
197 	tstruct;							\
198 									\
199 	return ret;							\
200 }
201 
202 #undef TRACE_EVENT_FORMAT_NOFILTER
203 #define TRACE_EVENT_FORMAT_NOFILTER(call, proto, args, fmt, tstruct,	\
204 				    tpfmt)
205 
206 #include "trace_event_types.h"
207