1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _DYNAMIC_DEBUG_H 3 #define _DYNAMIC_DEBUG_H 4 5 #if defined(CONFIG_JUMP_LABEL) 6 #include <linux/jump_label.h> 7 #endif 8 9 /* 10 * An instance of this structure is created in a special 11 * ELF section at every dynamic debug callsite. At runtime, 12 * the special section is treated as an array of these. 13 */ 14 struct _ddebug { 15 /* 16 * These fields are used to drive the user interface 17 * for selecting and displaying debug callsites. 18 */ 19 const char *modname; 20 const char *function; 21 const char *filename; 22 const char *format; 23 unsigned int lineno:18; 24 /* 25 * The flags field controls the behaviour at the callsite. 26 * The bits here are changed dynamically when the user 27 * writes commands to <debugfs>/dynamic_debug/control 28 */ 29 #define _DPRINTK_FLAGS_NONE 0 30 #define _DPRINTK_FLAGS_PRINT (1<<0) /* printk() a message using the format */ 31 #define _DPRINTK_FLAGS_INCL_MODNAME (1<<1) 32 #define _DPRINTK_FLAGS_INCL_FUNCNAME (1<<2) 33 #define _DPRINTK_FLAGS_INCL_LINENO (1<<3) 34 #define _DPRINTK_FLAGS_INCL_TID (1<<4) 35 36 #define _DPRINTK_FLAGS_INCL_ANY \ 37 (_DPRINTK_FLAGS_INCL_MODNAME | _DPRINTK_FLAGS_INCL_FUNCNAME |\ 38 _DPRINTK_FLAGS_INCL_LINENO | _DPRINTK_FLAGS_INCL_TID) 39 40 #if defined DEBUG 41 #define _DPRINTK_FLAGS_DEFAULT _DPRINTK_FLAGS_PRINT 42 #else 43 #define _DPRINTK_FLAGS_DEFAULT 0 44 #endif 45 unsigned int flags:8; 46 #ifdef CONFIG_JUMP_LABEL 47 union { 48 struct static_key_true dd_key_true; 49 struct static_key_false dd_key_false; 50 } key; 51 #endif 52 } __attribute__((aligned(8))); 53 54 55 56 #if defined(CONFIG_DYNAMIC_DEBUG_CORE) 57 58 int ddebug_add_module(struct _ddebug *tab, unsigned int n, 59 const char *modname); 60 extern int ddebug_remove_module(const char *mod_name); 61 extern __printf(2, 3) 62 void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...); 63 64 extern int ddebug_dyndbg_module_param_cb(char *param, char *val, 65 const char *modname); 66 67 struct device; 68 69 extern __printf(3, 4) 70 void __dynamic_dev_dbg(struct _ddebug *descriptor, const struct device *dev, 71 const char *fmt, ...); 72 73 struct net_device; 74 75 extern __printf(3, 4) 76 void __dynamic_netdev_dbg(struct _ddebug *descriptor, 77 const struct net_device *dev, 78 const char *fmt, ...); 79 80 struct ib_device; 81 82 extern __printf(3, 4) 83 void __dynamic_ibdev_dbg(struct _ddebug *descriptor, 84 const struct ib_device *ibdev, 85 const char *fmt, ...); 86 87 #define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) \ 88 static struct _ddebug __aligned(8) \ 89 __section("__dyndbg") name = { \ 90 .modname = KBUILD_MODNAME, \ 91 .function = __func__, \ 92 .filename = __FILE__, \ 93 .format = (fmt), \ 94 .lineno = __LINE__, \ 95 .flags = _DPRINTK_FLAGS_DEFAULT, \ 96 _DPRINTK_KEY_INIT \ 97 } 98 99 #ifdef CONFIG_JUMP_LABEL 100 101 #ifdef DEBUG 102 103 #define _DPRINTK_KEY_INIT .key.dd_key_true = (STATIC_KEY_TRUE_INIT) 104 105 #define DYNAMIC_DEBUG_BRANCH(descriptor) \ 106 static_branch_likely(&descriptor.key.dd_key_true) 107 #else 108 #define _DPRINTK_KEY_INIT .key.dd_key_false = (STATIC_KEY_FALSE_INIT) 109 110 #define DYNAMIC_DEBUG_BRANCH(descriptor) \ 111 static_branch_unlikely(&descriptor.key.dd_key_false) 112 #endif 113 114 #else /* !CONFIG_JUMP_LABEL */ 115 116 #define _DPRINTK_KEY_INIT 117 118 #ifdef DEBUG 119 #define DYNAMIC_DEBUG_BRANCH(descriptor) \ 120 likely(descriptor.flags & _DPRINTK_FLAGS_PRINT) 121 #else 122 #define DYNAMIC_DEBUG_BRANCH(descriptor) \ 123 unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) 124 #endif 125 126 #endif /* CONFIG_JUMP_LABEL */ 127 128 #define __dynamic_func_call(id, fmt, func, ...) do { \ 129 DEFINE_DYNAMIC_DEBUG_METADATA(id, fmt); \ 130 if (DYNAMIC_DEBUG_BRANCH(id)) \ 131 func(&id, ##__VA_ARGS__); \ 132 } while (0) 133 134 #define __dynamic_func_call_no_desc(id, fmt, func, ...) do { \ 135 DEFINE_DYNAMIC_DEBUG_METADATA(id, fmt); \ 136 if (DYNAMIC_DEBUG_BRANCH(id)) \ 137 func(__VA_ARGS__); \ 138 } while (0) 139 140 /* 141 * "Factory macro" for generating a call to func, guarded by a 142 * DYNAMIC_DEBUG_BRANCH. The dynamic debug descriptor will be 143 * initialized using the fmt argument. The function will be called with 144 * the address of the descriptor as first argument, followed by all 145 * the varargs. Note that fmt is repeated in invocations of this 146 * macro. 147 */ 148 #define _dynamic_func_call(fmt, func, ...) \ 149 __dynamic_func_call(__UNIQUE_ID(ddebug), fmt, func, ##__VA_ARGS__) 150 /* 151 * A variant that does the same, except that the descriptor is not 152 * passed as the first argument to the function; it is only called 153 * with precisely the macro's varargs. 154 */ 155 #define _dynamic_func_call_no_desc(fmt, func, ...) \ 156 __dynamic_func_call_no_desc(__UNIQUE_ID(ddebug), fmt, func, ##__VA_ARGS__) 157 158 #define dynamic_pr_debug(fmt, ...) \ 159 _dynamic_func_call(fmt, __dynamic_pr_debug, \ 160 pr_fmt(fmt), ##__VA_ARGS__) 161 162 #define dynamic_dev_dbg(dev, fmt, ...) \ 163 _dynamic_func_call(fmt,__dynamic_dev_dbg, \ 164 dev, fmt, ##__VA_ARGS__) 165 166 #define dynamic_netdev_dbg(dev, fmt, ...) \ 167 _dynamic_func_call(fmt, __dynamic_netdev_dbg, \ 168 dev, fmt, ##__VA_ARGS__) 169 170 #define dynamic_ibdev_dbg(dev, fmt, ...) \ 171 _dynamic_func_call(fmt, __dynamic_ibdev_dbg, \ 172 dev, fmt, ##__VA_ARGS__) 173 174 #define dynamic_hex_dump(prefix_str, prefix_type, rowsize, \ 175 groupsize, buf, len, ascii) \ 176 _dynamic_func_call_no_desc(__builtin_constant_p(prefix_str) ? prefix_str : "hexdump", \ 177 print_hex_dump, \ 178 KERN_DEBUG, prefix_str, prefix_type, \ 179 rowsize, groupsize, buf, len, ascii) 180 181 #else /* !CONFIG_DYNAMIC_DEBUG_CORE */ 182 183 #include <linux/string.h> 184 #include <linux/errno.h> 185 #include <linux/printk.h> 186 187 static inline int ddebug_add_module(struct _ddebug *tab, unsigned int n, 188 const char *modname) 189 { 190 return 0; 191 } 192 193 static inline int ddebug_remove_module(const char *mod) 194 { 195 return 0; 196 } 197 198 static inline int ddebug_dyndbg_module_param_cb(char *param, char *val, 199 const char *modname) 200 { 201 if (!strcmp(param, "dyndbg")) { 202 /* avoid pr_warn(), which wants pr_fmt() fully defined */ 203 printk(KERN_WARNING "dyndbg param is supported only in " 204 "CONFIG_DYNAMIC_DEBUG builds\n"); 205 return 0; /* allow and ignore */ 206 } 207 return -EINVAL; 208 } 209 210 #define dynamic_pr_debug(fmt, ...) \ 211 do { if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); } while (0) 212 #define dynamic_dev_dbg(dev, fmt, ...) \ 213 do { if (0) dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); } while (0) 214 #define dynamic_hex_dump(prefix_str, prefix_type, rowsize, \ 215 groupsize, buf, len, ascii) \ 216 do { if (0) \ 217 print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, \ 218 rowsize, groupsize, buf, len, ascii); \ 219 } while (0) 220 221 #endif /* !CONFIG_DYNAMIC_DEBUG_CORE */ 222 223 #endif 224