xref: /linux/include/trace/trace_events.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * Stage 1 of the trace events.
3  *
4  * Override the macros in <trace/trace_events.h> to include the following:
5  *
6  * struct trace_event_raw_<call> {
7  *	struct trace_entry		ent;
8  *	<type>				<item>;
9  *	<type2>				<item2>[<len>];
10  *	[...]
11  * };
12  *
13  * The <type> <item> is created by the __field(type, item) macro or
14  * the __array(type2, item2, len) macro.
15  * We simply do "type item;", and that will create the fields
16  * in the structure.
17  */
18 
19 #include <linux/trace_events.h>
20 
21 #ifndef TRACE_SYSTEM_VAR
22 #define TRACE_SYSTEM_VAR TRACE_SYSTEM
23 #endif
24 
25 #define __app__(x, y) str__##x##y
26 #define __app(x, y) __app__(x, y)
27 
28 #define TRACE_SYSTEM_STRING __app(TRACE_SYSTEM_VAR,__trace_system_name)
29 
30 #define TRACE_MAKE_SYSTEM_STR()				\
31 	static const char TRACE_SYSTEM_STRING[] =	\
32 		__stringify(TRACE_SYSTEM)
33 
34 TRACE_MAKE_SYSTEM_STR();
35 
36 #undef TRACE_DEFINE_ENUM
37 #define TRACE_DEFINE_ENUM(a)				\
38 	static struct trace_enum_map __used __initdata	\
39 	__##TRACE_SYSTEM##_##a =			\
40 	{						\
41 		.system = TRACE_SYSTEM_STRING,		\
42 		.enum_string = #a,			\
43 		.enum_value = a				\
44 	};						\
45 	static struct trace_enum_map __used		\
46 	__attribute__((section("_ftrace_enum_map")))	\
47 	*TRACE_SYSTEM##_##a = &__##TRACE_SYSTEM##_##a
48 
49 /*
50  * DECLARE_EVENT_CLASS can be used to add a generic function
51  * handlers for events. That is, if all events have the same
52  * parameters and just have distinct trace points.
53  * Each tracepoint can be defined with DEFINE_EVENT and that
54  * will map the DECLARE_EVENT_CLASS to the tracepoint.
55  *
56  * TRACE_EVENT is a one to one mapping between tracepoint and template.
57  */
58 #undef TRACE_EVENT
59 #define TRACE_EVENT(name, proto, args, tstruct, assign, print) \
60 	DECLARE_EVENT_CLASS(name,			       \
61 			     PARAMS(proto),		       \
62 			     PARAMS(args),		       \
63 			     PARAMS(tstruct),		       \
64 			     PARAMS(assign),		       \
65 			     PARAMS(print));		       \
66 	DEFINE_EVENT(name, name, PARAMS(proto), PARAMS(args));
67 
68 
69 #undef __field
70 #define __field(type, item)		type	item;
71 
72 #undef __field_ext
73 #define __field_ext(type, item, filter_type)	type	item;
74 
75 #undef __field_struct
76 #define __field_struct(type, item)	type	item;
77 
78 #undef __field_struct_ext
79 #define __field_struct_ext(type, item, filter_type)	type	item;
80 
81 #undef __array
82 #define __array(type, item, len)	type	item[len];
83 
84 #undef __dynamic_array
85 #define __dynamic_array(type, item, len) u32 __data_loc_##item;
86 
87 #undef __string
88 #define __string(item, src) __dynamic_array(char, item, -1)
89 
90 #undef __bitmask
91 #define __bitmask(item, nr_bits) __dynamic_array(char, item, -1)
92 
93 #undef TP_STRUCT__entry
94 #define TP_STRUCT__entry(args...) args
95 
96 #undef DECLARE_EVENT_CLASS
97 #define DECLARE_EVENT_CLASS(name, proto, args, tstruct, assign, print)	\
98 	struct trace_event_raw_##name {					\
99 		struct trace_entry	ent;				\
100 		tstruct							\
101 		char			__data[0];			\
102 	};								\
103 									\
104 	static struct trace_event_class event_class_##name;
105 
106 #undef DEFINE_EVENT
107 #define DEFINE_EVENT(template, name, proto, args)	\
108 	static struct trace_event_call	__used		\
109 	__attribute__((__aligned__(4))) event_##name
110 
111 #undef DEFINE_EVENT_FN
112 #define DEFINE_EVENT_FN(template, name, proto, args, reg, unreg)	\
113 	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))
114 
115 #undef DEFINE_EVENT_PRINT
116 #define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
117 	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))
118 
119 /* Callbacks are meaningless to ftrace. */
120 #undef TRACE_EVENT_FN
121 #define TRACE_EVENT_FN(name, proto, args, tstruct,			\
122 		assign, print, reg, unreg)				\
123 	TRACE_EVENT(name, PARAMS(proto), PARAMS(args),			\
124 		PARAMS(tstruct), PARAMS(assign), PARAMS(print))		\
125 
126 #undef TRACE_EVENT_FLAGS
127 #define TRACE_EVENT_FLAGS(name, value)					\
128 	__TRACE_EVENT_FLAGS(name, value)
129 
130 #undef TRACE_EVENT_PERF_PERM
131 #define TRACE_EVENT_PERF_PERM(name, expr...)				\
132 	__TRACE_EVENT_PERF_PERM(name, expr)
133 
134 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
135 
136 /*
137  * Stage 2 of the trace events.
138  *
139  * Include the following:
140  *
141  * struct trace_event_data_offsets_<call> {
142  *	u32				<item1>;
143  *	u32				<item2>;
144  *	[...]
145  * };
146  *
147  * The __dynamic_array() macro will create each u32 <item>, this is
148  * to keep the offset of each array from the beginning of the event.
149  * The size of an array is also encoded, in the higher 16 bits of <item>.
150  */
151 
152 #undef TRACE_DEFINE_ENUM
153 #define TRACE_DEFINE_ENUM(a)
154 
155 #undef __field
156 #define __field(type, item)
157 
158 #undef __field_ext
159 #define __field_ext(type, item, filter_type)
160 
161 #undef __field_struct
162 #define __field_struct(type, item)
163 
164 #undef __field_struct_ext
165 #define __field_struct_ext(type, item, filter_type)
166 
167 #undef __array
168 #define __array(type, item, len)
169 
170 #undef __dynamic_array
171 #define __dynamic_array(type, item, len)	u32 item;
172 
173 #undef __string
174 #define __string(item, src) __dynamic_array(char, item, -1)
175 
176 #undef __bitmask
177 #define __bitmask(item, nr_bits) __dynamic_array(unsigned long, item, -1)
178 
179 #undef DECLARE_EVENT_CLASS
180 #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
181 	struct trace_event_data_offsets_##call {			\
182 		tstruct;						\
183 	};
184 
185 #undef DEFINE_EVENT
186 #define DEFINE_EVENT(template, name, proto, args)
187 
188 #undef DEFINE_EVENT_PRINT
189 #define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
190 	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))
191 
192 #undef TRACE_EVENT_FLAGS
193 #define TRACE_EVENT_FLAGS(event, flag)
194 
195 #undef TRACE_EVENT_PERF_PERM
196 #define TRACE_EVENT_PERF_PERM(event, expr...)
197 
198 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
199 
200 /*
201  * Stage 3 of the trace events.
202  *
203  * Override the macros in <trace/trace_events.h> to include the following:
204  *
205  * enum print_line_t
206  * trace_raw_output_<call>(struct trace_iterator *iter, int flags)
207  * {
208  *	struct trace_seq *s = &iter->seq;
209  *	struct trace_event_raw_<call> *field; <-- defined in stage 1
210  *	struct trace_entry *entry;
211  *	struct trace_seq *p = &iter->tmp_seq;
212  *	int ret;
213  *
214  *	entry = iter->ent;
215  *
216  *	if (entry->type != event_<call>->event.type) {
217  *		WARN_ON_ONCE(1);
218  *		return TRACE_TYPE_UNHANDLED;
219  *	}
220  *
221  *	field = (typeof(field))entry;
222  *
223  *	trace_seq_init(p);
224  *	ret = trace_seq_printf(s, "%s: ", <call>);
225  *	if (ret)
226  *		ret = trace_seq_printf(s, <TP_printk> "\n");
227  *	if (!ret)
228  *		return TRACE_TYPE_PARTIAL_LINE;
229  *
230  *	return TRACE_TYPE_HANDLED;
231  * }
232  *
233  * This is the method used to print the raw event to the trace
234  * output format. Note, this is not needed if the data is read
235  * in binary.
236  */
237 
238 #undef __entry
239 #define __entry field
240 
241 #undef TP_printk
242 #define TP_printk(fmt, args...) fmt "\n", args
243 
244 #undef __get_dynamic_array
245 #define __get_dynamic_array(field)	\
246 		((void *)__entry + (__entry->__data_loc_##field & 0xffff))
247 
248 #undef __get_dynamic_array_len
249 #define __get_dynamic_array_len(field)	\
250 		((__entry->__data_loc_##field >> 16) & 0xffff)
251 
252 #undef __get_str
253 #define __get_str(field) (char *)__get_dynamic_array(field)
254 
255 #undef __get_bitmask
256 #define __get_bitmask(field)						\
257 	({								\
258 		void *__bitmask = __get_dynamic_array(field);		\
259 		unsigned int __bitmask_size;				\
260 		__bitmask_size = __get_dynamic_array_len(field);	\
261 		trace_print_bitmask_seq(p, __bitmask, __bitmask_size);	\
262 	})
263 
264 #undef __print_flags
265 #define __print_flags(flag, delim, flag_array...)			\
266 	({								\
267 		static const struct trace_print_flags __flags[] =	\
268 			{ flag_array, { -1, NULL }};			\
269 		trace_print_flags_seq(p, delim, flag, __flags);	\
270 	})
271 
272 #undef __print_symbolic
273 #define __print_symbolic(value, symbol_array...)			\
274 	({								\
275 		static const struct trace_print_flags symbols[] =	\
276 			{ symbol_array, { -1, NULL }};			\
277 		trace_print_symbols_seq(p, value, symbols);		\
278 	})
279 
280 #undef __print_symbolic_u64
281 #if BITS_PER_LONG == 32
282 #define __print_symbolic_u64(value, symbol_array...)			\
283 	({								\
284 		static const struct trace_print_flags_u64 symbols[] =	\
285 			{ symbol_array, { -1, NULL } };			\
286 		trace_print_symbols_seq_u64(p, value, symbols);	\
287 	})
288 #else
289 #define __print_symbolic_u64(value, symbol_array...)			\
290 			__print_symbolic(value, symbol_array)
291 #endif
292 
293 #undef __print_hex
294 #define __print_hex(buf, buf_len) trace_print_hex_seq(p, buf, buf_len)
295 
296 #undef __print_array
297 #define __print_array(array, count, el_size)				\
298 	({								\
299 		BUILD_BUG_ON(el_size != 1 && el_size != 2 &&		\
300 			     el_size != 4 && el_size != 8);		\
301 		trace_print_array_seq(p, array, count, el_size);	\
302 	})
303 
304 #undef DECLARE_EVENT_CLASS
305 #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
306 static notrace enum print_line_t					\
307 trace_raw_output_##call(struct trace_iterator *iter, int flags,		\
308 			struct trace_event *trace_event)		\
309 {									\
310 	struct trace_seq *s = &iter->seq;				\
311 	struct trace_seq __maybe_unused *p = &iter->tmp_seq;		\
312 	struct trace_event_raw_##call *field;				\
313 	int ret;							\
314 									\
315 	field = (typeof(field))iter->ent;				\
316 									\
317 	ret = trace_raw_output_prep(iter, trace_event);			\
318 	if (ret != TRACE_TYPE_HANDLED)					\
319 		return ret;						\
320 									\
321 	trace_seq_printf(s, print);					\
322 									\
323 	return trace_handle_return(s);					\
324 }									\
325 static struct trace_event_functions trace_event_type_funcs_##call = {	\
326 	.trace			= trace_raw_output_##call,		\
327 };
328 
329 #undef DEFINE_EVENT_PRINT
330 #define DEFINE_EVENT_PRINT(template, call, proto, args, print)		\
331 static notrace enum print_line_t					\
332 trace_raw_output_##call(struct trace_iterator *iter, int flags,		\
333 			 struct trace_event *event)			\
334 {									\
335 	struct trace_event_raw_##template *field;			\
336 	struct trace_entry *entry;					\
337 	struct trace_seq *p = &iter->tmp_seq;				\
338 									\
339 	entry = iter->ent;						\
340 									\
341 	if (entry->type != event_##call.event.type) {			\
342 		WARN_ON_ONCE(1);					\
343 		return TRACE_TYPE_UNHANDLED;				\
344 	}								\
345 									\
346 	field = (typeof(field))entry;					\
347 									\
348 	trace_seq_init(p);						\
349 	return trace_output_call(iter, #call, print);			\
350 }									\
351 static struct trace_event_functions trace_event_type_funcs_##call = {	\
352 	.trace			= trace_raw_output_##call,		\
353 };
354 
355 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
356 
357 #undef __field_ext
358 #define __field_ext(type, item, filter_type)				\
359 	ret = trace_define_field(event_call, #type, #item,		\
360 				 offsetof(typeof(field), item),		\
361 				 sizeof(field.item),			\
362 				 is_signed_type(type), filter_type);	\
363 	if (ret)							\
364 		return ret;
365 
366 #undef __field_struct_ext
367 #define __field_struct_ext(type, item, filter_type)			\
368 	ret = trace_define_field(event_call, #type, #item,		\
369 				 offsetof(typeof(field), item),		\
370 				 sizeof(field.item),			\
371 				 0, filter_type);			\
372 	if (ret)							\
373 		return ret;
374 
375 #undef __field
376 #define __field(type, item)	__field_ext(type, item, FILTER_OTHER)
377 
378 #undef __field_struct
379 #define __field_struct(type, item) __field_struct_ext(type, item, FILTER_OTHER)
380 
381 #undef __array
382 #define __array(type, item, len)					\
383 	do {								\
384 		char *type_str = #type"["__stringify(len)"]";		\
385 		BUILD_BUG_ON(len > MAX_FILTER_STR_VAL);			\
386 		ret = trace_define_field(event_call, type_str, #item,	\
387 				 offsetof(typeof(field), item),		\
388 				 sizeof(field.item),			\
389 				 is_signed_type(type), FILTER_OTHER);	\
390 		if (ret)						\
391 			return ret;					\
392 	} while (0);
393 
394 #undef __dynamic_array
395 #define __dynamic_array(type, item, len)				       \
396 	ret = trace_define_field(event_call, "__data_loc " #type "[]", #item,  \
397 				 offsetof(typeof(field), __data_loc_##item),   \
398 				 sizeof(field.__data_loc_##item),	       \
399 				 is_signed_type(type), FILTER_OTHER);
400 
401 #undef __string
402 #define __string(item, src) __dynamic_array(char, item, -1)
403 
404 #undef __bitmask
405 #define __bitmask(item, nr_bits) __dynamic_array(unsigned long, item, -1)
406 
407 #undef DECLARE_EVENT_CLASS
408 #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, func, print)	\
409 static int notrace __init						\
410 trace_event_define_fields_##call(struct trace_event_call *event_call)	\
411 {									\
412 	struct trace_event_raw_##call field;				\
413 	int ret;							\
414 									\
415 	tstruct;							\
416 									\
417 	return ret;							\
418 }
419 
420 #undef DEFINE_EVENT
421 #define DEFINE_EVENT(template, name, proto, args)
422 
423 #undef DEFINE_EVENT_PRINT
424 #define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
425 	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))
426 
427 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
428 
429 /*
430  * remember the offset of each array from the beginning of the event.
431  */
432 
433 #undef __entry
434 #define __entry entry
435 
436 #undef __field
437 #define __field(type, item)
438 
439 #undef __field_ext
440 #define __field_ext(type, item, filter_type)
441 
442 #undef __field_struct
443 #define __field_struct(type, item)
444 
445 #undef __field_struct_ext
446 #define __field_struct_ext(type, item, filter_type)
447 
448 #undef __array
449 #define __array(type, item, len)
450 
451 #undef __dynamic_array
452 #define __dynamic_array(type, item, len)				\
453 	__item_length = (len) * sizeof(type);				\
454 	__data_offsets->item = __data_size +				\
455 			       offsetof(typeof(*entry), __data);	\
456 	__data_offsets->item |= __item_length << 16;			\
457 	__data_size += __item_length;
458 
459 #undef __string
460 #define __string(item, src) __dynamic_array(char, item,			\
461 		    strlen((src) ? (const char *)(src) : "(null)") + 1)
462 
463 /*
464  * __bitmask_size_in_bytes_raw is the number of bytes needed to hold
465  * num_possible_cpus().
466  */
467 #define __bitmask_size_in_bytes_raw(nr_bits)	\
468 	(((nr_bits) + 7) / 8)
469 
470 #define __bitmask_size_in_longs(nr_bits)			\
471 	((__bitmask_size_in_bytes_raw(nr_bits) +		\
472 	  ((BITS_PER_LONG / 8) - 1)) / (BITS_PER_LONG / 8))
473 
474 /*
475  * __bitmask_size_in_bytes is the number of bytes needed to hold
476  * num_possible_cpus() padded out to the nearest long. This is what
477  * is saved in the buffer, just to be consistent.
478  */
479 #define __bitmask_size_in_bytes(nr_bits)				\
480 	(__bitmask_size_in_longs(nr_bits) * (BITS_PER_LONG / 8))
481 
482 #undef __bitmask
483 #define __bitmask(item, nr_bits) __dynamic_array(unsigned long, item,	\
484 					 __bitmask_size_in_longs(nr_bits))
485 
486 #undef DECLARE_EVENT_CLASS
487 #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
488 static inline notrace int trace_event_get_offsets_##call(		\
489 	struct trace_event_data_offsets_##call *__data_offsets, proto)	\
490 {									\
491 	int __data_size = 0;						\
492 	int __maybe_unused __item_length;				\
493 	struct trace_event_raw_##call __maybe_unused *entry;		\
494 									\
495 	tstruct;							\
496 									\
497 	return __data_size;						\
498 }
499 
500 #undef DEFINE_EVENT
501 #define DEFINE_EVENT(template, name, proto, args)
502 
503 #undef DEFINE_EVENT_PRINT
504 #define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
505 	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))
506 
507 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
508 
509