Linux kernel mirror (for testing)
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linux
1#ifndef _DYNAMIC_DEBUG_H
2#define _DYNAMIC_DEBUG_H
3
4#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
5#include <linux/jump_label.h>
6#endif
7
8/*
9 * An instance of this structure is created in a special
10 * ELF section at every dynamic debug callsite. At runtime,
11 * the special section is treated as an array of these.
12 */
13struct _ddebug {
14 /*
15 * These fields are used to drive the user interface
16 * for selecting and displaying debug callsites.
17 */
18 const char *modname;
19 const char *function;
20 const char *filename;
21 const char *format;
22 unsigned int lineno:18;
23 /*
24 * The flags field controls the behaviour at the callsite.
25 * The bits here are changed dynamically when the user
26 * writes commands to <debugfs>/dynamic_debug/control
27 */
28#define _DPRINTK_FLAGS_NONE 0
29#define _DPRINTK_FLAGS_PRINT (1<<0) /* printk() a message using the format */
30#define _DPRINTK_FLAGS_INCL_MODNAME (1<<1)
31#define _DPRINTK_FLAGS_INCL_FUNCNAME (1<<2)
32#define _DPRINTK_FLAGS_INCL_LINENO (1<<3)
33#define _DPRINTK_FLAGS_INCL_TID (1<<4)
34#if defined DEBUG
35#define _DPRINTK_FLAGS_DEFAULT _DPRINTK_FLAGS_PRINT
36#else
37#define _DPRINTK_FLAGS_DEFAULT 0
38#endif
39 unsigned int flags:8;
40#ifdef HAVE_JUMP_LABEL
41 union {
42 struct static_key_true dd_key_true;
43 struct static_key_false dd_key_false;
44 } key;
45#endif
46} __attribute__((aligned(8)));
47
48
49int ddebug_add_module(struct _ddebug *tab, unsigned int n,
50 const char *modname);
51
52#if defined(CONFIG_DYNAMIC_DEBUG)
53extern int ddebug_remove_module(const char *mod_name);
54extern __printf(2, 3)
55void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...);
56
57extern int ddebug_dyndbg_module_param_cb(char *param, char *val,
58 const char *modname);
59
60struct device;
61
62extern __printf(3, 4)
63void __dynamic_dev_dbg(struct _ddebug *descriptor, const struct device *dev,
64 const char *fmt, ...);
65
66struct net_device;
67
68extern __printf(3, 4)
69void __dynamic_netdev_dbg(struct _ddebug *descriptor,
70 const struct net_device *dev,
71 const char *fmt, ...);
72
73#define DEFINE_DYNAMIC_DEBUG_METADATA_KEY(name, fmt, key, init) \
74 static struct _ddebug __aligned(8) \
75 __attribute__((section("__verbose"))) name = { \
76 .modname = KBUILD_MODNAME, \
77 .function = __func__, \
78 .filename = __FILE__, \
79 .format = (fmt), \
80 .lineno = __LINE__, \
81 .flags = _DPRINTK_FLAGS_DEFAULT, \
82 dd_key_init(key, init) \
83 }
84
85#ifdef HAVE_JUMP_LABEL
86
87#define dd_key_init(key, init) key = (init)
88
89#ifdef DEBUG
90#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) \
91 DEFINE_DYNAMIC_DEBUG_METADATA_KEY(name, fmt, .key.dd_key_true, \
92 (STATIC_KEY_TRUE_INIT))
93
94#define DYNAMIC_DEBUG_BRANCH(descriptor) \
95 static_branch_likely(&descriptor.key.dd_key_true)
96#else
97#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) \
98 DEFINE_DYNAMIC_DEBUG_METADATA_KEY(name, fmt, .key.dd_key_false, \
99 (STATIC_KEY_FALSE_INIT))
100
101#define DYNAMIC_DEBUG_BRANCH(descriptor) \
102 static_branch_unlikely(&descriptor.key.dd_key_false)
103#endif
104
105#else
106
107#define dd_key_init(key, init)
108
109#define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) \
110 DEFINE_DYNAMIC_DEBUG_METADATA_KEY(name, fmt, 0, 0)
111
112#ifdef DEBUG
113#define DYNAMIC_DEBUG_BRANCH(descriptor) \
114 likely(descriptor.flags & _DPRINTK_FLAGS_PRINT)
115#else
116#define DYNAMIC_DEBUG_BRANCH(descriptor) \
117 unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT)
118#endif
119
120#endif
121
122#define dynamic_pr_debug(fmt, ...) \
123do { \
124 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \
125 if (DYNAMIC_DEBUG_BRANCH(descriptor)) \
126 __dynamic_pr_debug(&descriptor, pr_fmt(fmt), \
127 ##__VA_ARGS__); \
128} while (0)
129
130#define dynamic_dev_dbg(dev, fmt, ...) \
131do { \
132 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \
133 if (DYNAMIC_DEBUG_BRANCH(descriptor)) \
134 __dynamic_dev_dbg(&descriptor, dev, fmt, \
135 ##__VA_ARGS__); \
136} while (0)
137
138#define dynamic_netdev_dbg(dev, fmt, ...) \
139do { \
140 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, fmt); \
141 if (DYNAMIC_DEBUG_BRANCH(descriptor)) \
142 __dynamic_netdev_dbg(&descriptor, dev, fmt, \
143 ##__VA_ARGS__); \
144} while (0)
145
146#define dynamic_hex_dump(prefix_str, prefix_type, rowsize, \
147 groupsize, buf, len, ascii) \
148do { \
149 DEFINE_DYNAMIC_DEBUG_METADATA(descriptor, \
150 __builtin_constant_p(prefix_str) ? prefix_str : "hexdump");\
151 if (DYNAMIC_DEBUG_BRANCH(descriptor)) \
152 print_hex_dump(KERN_DEBUG, prefix_str, \
153 prefix_type, rowsize, groupsize, \
154 buf, len, ascii); \
155} while (0)
156
157#else
158
159#include <linux/string.h>
160#include <linux/errno.h>
161
162static inline int ddebug_remove_module(const char *mod)
163{
164 return 0;
165}
166
167static inline int ddebug_dyndbg_module_param_cb(char *param, char *val,
168 const char *modname)
169{
170 if (strstr(param, "dyndbg")) {
171 /* avoid pr_warn(), which wants pr_fmt() fully defined */
172 printk(KERN_WARNING "dyndbg param is supported only in "
173 "CONFIG_DYNAMIC_DEBUG builds\n");
174 return 0; /* allow and ignore */
175 }
176 return -EINVAL;
177}
178
179#define dynamic_pr_debug(fmt, ...) \
180 do { if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); } while (0)
181#define dynamic_dev_dbg(dev, fmt, ...) \
182 do { if (0) dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); } while (0)
183#endif
184
185#endif