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 | #include <linux/build_bug.h> |
10 | |
11 | /* |
12 | * An instance of this structure is created in a special |
13 | * ELF section at every dynamic debug callsite. At runtime, |
14 | * the special section is treated as an array of these. |
15 | */ |
16 | struct _ddebug { |
17 | /* |
18 | * These fields are used to drive the user interface |
19 | * for selecting and displaying debug callsites. |
20 | */ |
21 | const char *modname; |
22 | const char *function; |
23 | const char *filename; |
24 | const char *format; |
25 | unsigned int lineno:18; |
26 | #define CLS_BITS 6 |
27 | unsigned int class_id:CLS_BITS; |
28 | #define _DPRINTK_CLASS_DFLT ((1 << CLS_BITS) - 1) |
29 | /* |
30 | * The flags field controls the behaviour at the callsite. |
31 | * The bits here are changed dynamically when the user |
32 | * writes commands to <debugfs>/dynamic_debug/control |
33 | */ |
34 | #define _DPRINTK_FLAGS_NONE 0 |
35 | #define _DPRINTK_FLAGS_PRINT (1<<0) /* printk() a message using the format */ |
36 | #define _DPRINTK_FLAGS_INCL_MODNAME (1<<1) |
37 | #define _DPRINTK_FLAGS_INCL_FUNCNAME (1<<2) |
38 | #define _DPRINTK_FLAGS_INCL_LINENO (1<<3) |
39 | #define _DPRINTK_FLAGS_INCL_TID (1<<4) |
40 | #define _DPRINTK_FLAGS_INCL_SOURCENAME (1<<5) |
41 | |
42 | #define _DPRINTK_FLAGS_INCL_ANY \ |
43 | (_DPRINTK_FLAGS_INCL_MODNAME | _DPRINTK_FLAGS_INCL_FUNCNAME |\ |
44 | _DPRINTK_FLAGS_INCL_LINENO | _DPRINTK_FLAGS_INCL_TID |\ |
45 | _DPRINTK_FLAGS_INCL_SOURCENAME) |
46 | |
47 | #if defined DEBUG |
48 | #define _DPRINTK_FLAGS_DEFAULT _DPRINTK_FLAGS_PRINT |
49 | #else |
50 | #define _DPRINTK_FLAGS_DEFAULT 0 |
51 | #endif |
52 | unsigned int flags:8; |
53 | #ifdef CONFIG_JUMP_LABEL |
54 | union { |
55 | struct static_key_true dd_key_true; |
56 | struct static_key_false dd_key_false; |
57 | } key; |
58 | #endif |
59 | } __attribute__((aligned(8))); |
60 | |
61 | enum class_map_type { |
62 | DD_CLASS_TYPE_DISJOINT_BITS, |
63 | /** |
64 | * DD_CLASS_TYPE_DISJOINT_BITS: classes are independent, one per bit. |
65 | * expecting hex input. Built for drm.debug, basis for other types. |
66 | */ |
67 | DD_CLASS_TYPE_LEVEL_NUM, |
68 | /** |
69 | * DD_CLASS_TYPE_LEVEL_NUM: input is numeric level, 0-N. |
70 | * N turns on just bits N-1 .. 0, so N=0 turns all bits off. |
71 | */ |
72 | DD_CLASS_TYPE_DISJOINT_NAMES, |
73 | /** |
74 | * DD_CLASS_TYPE_DISJOINT_NAMES: input is a CSV of [+-]CLASS_NAMES, |
75 | * classes are independent, like _DISJOINT_BITS. |
76 | */ |
77 | DD_CLASS_TYPE_LEVEL_NAMES, |
78 | /** |
79 | * DD_CLASS_TYPE_LEVEL_NAMES: input is a CSV of [+-]CLASS_NAMES, |
80 | * intended for names like: INFO,DEBUG,TRACE, with a module prefix |
81 | * avoid EMERG,ALERT,CRIT,ERR,WARNING: they're not debug |
82 | */ |
83 | }; |
84 | |
85 | struct ddebug_class_map { |
86 | struct list_head link; |
87 | struct module *mod; |
88 | const char *mod_name; /* needed for builtins */ |
89 | const char **class_names; |
90 | const int length; |
91 | const int base; /* index of 1st .class_id, allows split/shared space */ |
92 | enum class_map_type map_type; |
93 | }; |
94 | |
95 | /** |
96 | * DECLARE_DYNDBG_CLASSMAP - declare classnames known by a module |
97 | * @_var: a struct ddebug_class_map, passed to module_param_cb |
98 | * @_type: enum class_map_type, chooses bits/verbose, numeric/symbolic |
99 | * @_base: offset of 1st class-name. splits .class_id space |
100 | * @classes: class-names used to control class'd prdbgs |
101 | */ |
102 | #define DECLARE_DYNDBG_CLASSMAP(_var, _maptype, _base, ...) \ |
103 | static const char *_var##_classnames[] = { __VA_ARGS__ }; \ |
104 | static struct ddebug_class_map __aligned(8) __used \ |
105 | __section("__dyndbg_classes") _var = { \ |
106 | .mod = THIS_MODULE, \ |
107 | .mod_name = KBUILD_MODNAME, \ |
108 | .base = _base, \ |
109 | .map_type = _maptype, \ |
110 | .length = NUM_TYPE_ARGS(char*, __VA_ARGS__), \ |
111 | .class_names = _var##_classnames, \ |
112 | } |
113 | #define NUM_TYPE_ARGS(eltype, ...) \ |
114 | (sizeof((eltype[]){__VA_ARGS__}) / sizeof(eltype)) |
115 | |
116 | /* encapsulate linker provided built-in (or module) dyndbg data */ |
117 | struct _ddebug_info { |
118 | struct _ddebug *descs; |
119 | struct ddebug_class_map *classes; |
120 | unsigned int num_descs; |
121 | unsigned int num_classes; |
122 | }; |
123 | |
124 | struct ddebug_class_param { |
125 | union { |
126 | unsigned long *bits; |
127 | unsigned int *lvl; |
128 | }; |
129 | char flags[8]; |
130 | const struct ddebug_class_map *map; |
131 | }; |
132 | |
133 | /* |
134 | * pr_debug() and friends are globally enabled or modules have selectively |
135 | * enabled them. |
136 | */ |
137 | #if defined(CONFIG_DYNAMIC_DEBUG) || \ |
138 | (defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE)) |
139 | |
140 | extern __printf(2, 3) |
141 | void __dynamic_pr_debug(struct _ddebug *descriptor, const char *fmt, ...); |
142 | |
143 | struct device; |
144 | |
145 | extern __printf(3, 4) |
146 | void __dynamic_dev_dbg(struct _ddebug *descriptor, const struct device *dev, |
147 | const char *fmt, ...); |
148 | |
149 | struct net_device; |
150 | |
151 | extern __printf(3, 4) |
152 | void __dynamic_netdev_dbg(struct _ddebug *descriptor, |
153 | const struct net_device *dev, |
154 | const char *fmt, ...); |
155 | |
156 | struct ib_device; |
157 | |
158 | extern __printf(3, 4) |
159 | void __dynamic_ibdev_dbg(struct _ddebug *descriptor, |
160 | const struct ib_device *ibdev, |
161 | const char *fmt, ...); |
162 | |
163 | #define DEFINE_DYNAMIC_DEBUG_METADATA_CLS(name, cls, fmt) \ |
164 | static struct _ddebug __aligned(8) \ |
165 | __section("__dyndbg") name = { \ |
166 | .modname = KBUILD_MODNAME, \ |
167 | .function = __func__, \ |
168 | .filename = __FILE__, \ |
169 | .format = (fmt), \ |
170 | .lineno = __LINE__, \ |
171 | .flags = _DPRINTK_FLAGS_DEFAULT, \ |
172 | .class_id = cls, \ |
173 | _DPRINTK_KEY_INIT \ |
174 | }; \ |
175 | BUILD_BUG_ON_MSG(cls > _DPRINTK_CLASS_DFLT, \ |
176 | "classid value overflow") |
177 | |
178 | #define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) \ |
179 | DEFINE_DYNAMIC_DEBUG_METADATA_CLS(name, _DPRINTK_CLASS_DFLT, fmt) |
180 | |
181 | #ifdef CONFIG_JUMP_LABEL |
182 | |
183 | #ifdef DEBUG |
184 | |
185 | #define _DPRINTK_KEY_INIT .key.dd_key_true = (STATIC_KEY_TRUE_INIT) |
186 | |
187 | #define DYNAMIC_DEBUG_BRANCH(descriptor) \ |
188 | static_branch_likely(&descriptor.key.dd_key_true) |
189 | #else |
190 | #define _DPRINTK_KEY_INIT .key.dd_key_false = (STATIC_KEY_FALSE_INIT) |
191 | |
192 | #define DYNAMIC_DEBUG_BRANCH(descriptor) \ |
193 | static_branch_unlikely(&descriptor.key.dd_key_false) |
194 | #endif |
195 | |
196 | #else /* !CONFIG_JUMP_LABEL */ |
197 | |
198 | #define _DPRINTK_KEY_INIT |
199 | |
200 | #ifdef DEBUG |
201 | #define DYNAMIC_DEBUG_BRANCH(descriptor) \ |
202 | likely(descriptor.flags & _DPRINTK_FLAGS_PRINT) |
203 | #else |
204 | #define DYNAMIC_DEBUG_BRANCH(descriptor) \ |
205 | unlikely(descriptor.flags & _DPRINTK_FLAGS_PRINT) |
206 | #endif |
207 | |
208 | #endif /* CONFIG_JUMP_LABEL */ |
209 | |
210 | /* |
211 | * Factory macros: ($prefix)dynamic_func_call($suffix) |
212 | * |
213 | * Lower layer (with __ prefix) gets the callsite metadata, and wraps |
214 | * the func inside a debug-branch/static-key construct. Upper layer |
215 | * (with _ prefix) does the UNIQUE_ID once, so that lower can ref the |
216 | * name/label multiple times, and tie the elements together. |
217 | * Multiple flavors: |
218 | * (|_cls): adds in _DPRINT_CLASS_DFLT as needed |
219 | * (|_no_desc): former gets callsite descriptor as 1st arg (for prdbgs) |
220 | */ |
221 | #define __dynamic_func_call_cls(id, cls, fmt, func, ...) do { \ |
222 | DEFINE_DYNAMIC_DEBUG_METADATA_CLS(id, cls, fmt); \ |
223 | if (DYNAMIC_DEBUG_BRANCH(id)) \ |
224 | func(&id, ##__VA_ARGS__); \ |
225 | } while (0) |
226 | #define __dynamic_func_call(id, fmt, func, ...) \ |
227 | __dynamic_func_call_cls(id, _DPRINTK_CLASS_DFLT, fmt, \ |
228 | func, ##__VA_ARGS__) |
229 | |
230 | #define __dynamic_func_call_cls_no_desc(id, cls, fmt, func, ...) do { \ |
231 | DEFINE_DYNAMIC_DEBUG_METADATA_CLS(id, cls, fmt); \ |
232 | if (DYNAMIC_DEBUG_BRANCH(id)) \ |
233 | func(__VA_ARGS__); \ |
234 | } while (0) |
235 | #define __dynamic_func_call_no_desc(id, fmt, func, ...) \ |
236 | __dynamic_func_call_cls_no_desc(id, _DPRINTK_CLASS_DFLT, \ |
237 | fmt, func, ##__VA_ARGS__) |
238 | |
239 | /* |
240 | * "Factory macro" for generating a call to func, guarded by a |
241 | * DYNAMIC_DEBUG_BRANCH. The dynamic debug descriptor will be |
242 | * initialized using the fmt argument. The function will be called with |
243 | * the address of the descriptor as first argument, followed by all |
244 | * the varargs. Note that fmt is repeated in invocations of this |
245 | * macro. |
246 | */ |
247 | #define _dynamic_func_call_cls(cls, fmt, func, ...) \ |
248 | __dynamic_func_call_cls(__UNIQUE_ID(ddebug), cls, fmt, func, ##__VA_ARGS__) |
249 | #define _dynamic_func_call(fmt, func, ...) \ |
250 | _dynamic_func_call_cls(_DPRINTK_CLASS_DFLT, fmt, func, ##__VA_ARGS__) |
251 | |
252 | /* |
253 | * A variant that does the same, except that the descriptor is not |
254 | * passed as the first argument to the function; it is only called |
255 | * with precisely the macro's varargs. |
256 | */ |
257 | #define _dynamic_func_call_cls_no_desc(cls, fmt, func, ...) \ |
258 | __dynamic_func_call_cls_no_desc(__UNIQUE_ID(ddebug), cls, fmt, \ |
259 | func, ##__VA_ARGS__) |
260 | #define _dynamic_func_call_no_desc(fmt, func, ...) \ |
261 | _dynamic_func_call_cls_no_desc(_DPRINTK_CLASS_DFLT, fmt, \ |
262 | func, ##__VA_ARGS__) |
263 | |
264 | #define dynamic_pr_debug_cls(cls, fmt, ...) \ |
265 | _dynamic_func_call_cls(cls, fmt, __dynamic_pr_debug, \ |
266 | pr_fmt(fmt), ##__VA_ARGS__) |
267 | |
268 | #define dynamic_pr_debug(fmt, ...) \ |
269 | _dynamic_func_call(fmt, __dynamic_pr_debug, \ |
270 | pr_fmt(fmt), ##__VA_ARGS__) |
271 | |
272 | #define dynamic_dev_dbg(dev, fmt, ...) \ |
273 | _dynamic_func_call(fmt, __dynamic_dev_dbg, \ |
274 | dev, fmt, ##__VA_ARGS__) |
275 | |
276 | #define dynamic_netdev_dbg(dev, fmt, ...) \ |
277 | _dynamic_func_call(fmt, __dynamic_netdev_dbg, \ |
278 | dev, fmt, ##__VA_ARGS__) |
279 | |
280 | #define dynamic_ibdev_dbg(dev, fmt, ...) \ |
281 | _dynamic_func_call(fmt, __dynamic_ibdev_dbg, \ |
282 | dev, fmt, ##__VA_ARGS__) |
283 | |
284 | #define dynamic_hex_dump(prefix_str, prefix_type, rowsize, \ |
285 | groupsize, buf, len, ascii) \ |
286 | _dynamic_func_call_no_desc(__builtin_constant_p(prefix_str) ? prefix_str : "hexdump", \ |
287 | print_hex_dump, \ |
288 | KERN_DEBUG, prefix_str, prefix_type, \ |
289 | rowsize, groupsize, buf, len, ascii) |
290 | |
291 | /* for test only, generally expect drm.debug style macro wrappers */ |
292 | #define __pr_debug_cls(cls, fmt, ...) do { \ |
293 | BUILD_BUG_ON_MSG(!__builtin_constant_p(cls), \ |
294 | "expecting constant class int/enum"); \ |
295 | dynamic_pr_debug_cls(cls, fmt, ##__VA_ARGS__); \ |
296 | } while (0) |
297 | |
298 | #else /* !(CONFIG_DYNAMIC_DEBUG || (CONFIG_DYNAMIC_DEBUG_CORE && DYNAMIC_DEBUG_MODULE)) */ |
299 | |
300 | #include <linux/string.h> |
301 | #include <linux/errno.h> |
302 | #include <linux/printk.h> |
303 | |
304 | #define DEFINE_DYNAMIC_DEBUG_METADATA(name, fmt) |
305 | #define DYNAMIC_DEBUG_BRANCH(descriptor) false |
306 | |
307 | #define dynamic_pr_debug(fmt, ...) \ |
308 | do { if (0) printk(KERN_DEBUG pr_fmt(fmt), ##__VA_ARGS__); } while (0) |
309 | #define dynamic_dev_dbg(dev, fmt, ...) \ |
310 | do { if (0) dev_printk(KERN_DEBUG, dev, fmt, ##__VA_ARGS__); } while (0) |
311 | #define dynamic_hex_dump(prefix_str, prefix_type, rowsize, \ |
312 | groupsize, buf, len, ascii) \ |
313 | do { if (0) \ |
314 | print_hex_dump(KERN_DEBUG, prefix_str, prefix_type, \ |
315 | rowsize, groupsize, buf, len, ascii); \ |
316 | } while (0) |
317 | |
318 | #endif /* CONFIG_DYNAMIC_DEBUG || (CONFIG_DYNAMIC_DEBUG_CORE && DYNAMIC_DEBUG_MODULE) */ |
319 | |
320 | |
321 | #ifdef CONFIG_DYNAMIC_DEBUG_CORE |
322 | |
323 | extern int ddebug_dyndbg_module_param_cb(char *param, char *val, |
324 | const char *modname); |
325 | struct kernel_param; |
326 | int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp); |
327 | int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp); |
328 | |
329 | #else |
330 | |
331 | static inline int ddebug_dyndbg_module_param_cb(char *param, char *val, |
332 | const char *modname) |
333 | { |
334 | if (!strcmp(param, "dyndbg" )) { |
335 | /* avoid pr_warn(), which wants pr_fmt() fully defined */ |
336 | printk(KERN_WARNING "dyndbg param is supported only in " |
337 | "CONFIG_DYNAMIC_DEBUG builds\n" ); |
338 | return 0; /* allow and ignore */ |
339 | } |
340 | return -EINVAL; |
341 | } |
342 | |
343 | struct kernel_param; |
344 | static inline int param_set_dyndbg_classes(const char *instr, const struct kernel_param *kp) |
345 | { return 0; } |
346 | static inline int param_get_dyndbg_classes(char *buffer, const struct kernel_param *kp) |
347 | { return 0; } |
348 | |
349 | #endif |
350 | |
351 | |
352 | extern const struct kernel_param_ops param_ops_dyndbg_classes; |
353 | |
354 | #endif /* _DYNAMIC_DEBUG_H */ |
355 | |