Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[sfrench/cifs-2.6.git] / kernel / trace / trace_export.c
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 */
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 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)     \
64 struct ____ftrace_##name {                                              \
65         tstruct                                                         \
66 };                                                                      \
67 static 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)     \
135 static int __init                                                       \
136 ftrace_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                                                                         \
174 struct 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                                                                         \
181 struct 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 };                                                                      \
190 struct 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
198 bool ftrace_event_is_function(struct trace_event_call *call)
199 {
200         return call == &event_function;
201 }
202
203 #include "trace_entries.h"