xref: /openbmc/linux/kernel/trace/trace_export.c (revision b627b4ed)
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 #undef TRACE_FIELD
23 #define TRACE_FIELD(type, item, assign)					\
24 	ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"	\
25 			       "offset:%u;\tsize:%u;\n",		\
26 			       (unsigned int)offsetof(typeof(field), item), \
27 			       (unsigned int)sizeof(field.item));	\
28 	if (!ret)							\
29 		return 0;
30 
31 
32 #undef TRACE_FIELD_SPECIAL
33 #define TRACE_FIELD_SPECIAL(type_item, item, cmd)			\
34 	ret = trace_seq_printf(s, "\tfield special:" #type_item ";\t"	\
35 			       "offset:%u;\tsize:%u;\n",		\
36 			       (unsigned int)offsetof(typeof(field), item), \
37 			       (unsigned int)sizeof(field.item));	\
38 	if (!ret)							\
39 		return 0;
40 
41 #undef TRACE_FIELD_ZERO_CHAR
42 #define TRACE_FIELD_ZERO_CHAR(item)					\
43 	ret = trace_seq_printf(s, "\tfield:char " #item ";\t"		\
44 			       "offset:%u;\tsize:0;\n",			\
45 			       (unsigned int)offsetof(typeof(field), item)); \
46 	if (!ret)							\
47 		return 0;
48 
49 
50 #undef TP_RAW_FMT
51 #define TP_RAW_FMT(args...) args
52 
53 #undef TRACE_EVENT_FORMAT
54 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)	\
55 static int								\
56 ftrace_format_##call(struct trace_seq *s)				\
57 {									\
58 	struct args field;						\
59 	int ret;							\
60 									\
61 	tstruct;							\
62 									\
63 	trace_seq_printf(s, "\nprint fmt: \"%s\"\n", tpfmt);		\
64 									\
65 	return ret;							\
66 }
67 
68 #include "trace_event_types.h"
69 
70 #undef TRACE_ZERO_CHAR
71 #define TRACE_ZERO_CHAR(arg)
72 
73 #undef TRACE_FIELD
74 #define TRACE_FIELD(type, item, assign)\
75 	entry->item = assign;
76 
77 #undef TRACE_FIELD
78 #define TRACE_FIELD(type, item, assign)\
79 	entry->item = assign;
80 
81 #undef TP_CMD
82 #define TP_CMD(cmd...)	cmd
83 
84 #undef TRACE_ENTRY
85 #define TRACE_ENTRY	entry
86 
87 #undef TRACE_FIELD_SPECIAL
88 #define TRACE_FIELD_SPECIAL(type_item, item, cmd) \
89 	cmd;
90 
91 #undef TRACE_EVENT_FORMAT
92 #define TRACE_EVENT_FORMAT(call, proto, args, fmt, tstruct, tpfmt)	\
93 									\
94 static struct ftrace_event_call __used					\
95 __attribute__((__aligned__(4)))						\
96 __attribute__((section("_ftrace_events"))) event_##call = {		\
97 	.name			= #call,				\
98 	.id			= proto,				\
99 	.system			= __stringify(TRACE_SYSTEM),		\
100 	.show_format		= ftrace_format_##call,			\
101 }
102 #include "trace_event_types.h"
103