ftrace.h 21 KB
Newer Older
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
/*
 * Stage 1 of the trace events.
 *
 * Override the macros in <trace/trace_events.h> to include the following:
 *
 * struct ftrace_raw_<call> {
 *	struct trace_entry		ent;
 *	<type>				<item>;
 *	<type2>				<item2>[<len>];
 *	[...]
 * };
 *
 * The <type> <item> is created by the __field(type, item) macro or
 * the __array(type2, item2, len) macro.
 * We simply do "type item;", and that will create the fields
 * in the structure.
 */

#include <linux/ftrace_event.h>

21
/*
22
 * DECLARE_EVENT_CLASS can be used to add a generic function
23
24
25
 * handlers for events. That is, if all events have the same
 * parameters and just have distinct trace points.
 * Each tracepoint can be defined with DEFINE_EVENT and that
26
 * will map the DECLARE_EVENT_CLASS to the tracepoint.
27
28
29
30
31
 *
 * TRACE_EVENT is a one to one mapping between tracepoint and template.
 */
#undef TRACE_EVENT
#define TRACE_EVENT(name, proto, args, tstruct, assign, print) \
32
	DECLARE_EVENT_CLASS(name,			       \
33
34
35
36
37
38
39
40
			     PARAMS(proto),		       \
			     PARAMS(args),		       \
			     PARAMS(tstruct),		       \
			     PARAMS(assign),		       \
			     PARAMS(print));		       \
	DEFINE_EVENT(name, name, PARAMS(proto), PARAMS(args));


41
42
43
#undef __field
#define __field(type, item)		type	item;

44
45
46
#undef __field_ext
#define __field_ext(type, item, filter_type)	type	item;

47
48
49
#undef __array
#define __array(type, item, len)	type	item[len];

50
#undef __dynamic_array
51
#define __dynamic_array(type, item, len) u32 __data_loc_##item;
52

53
#undef __string
54
#define __string(item, src) __dynamic_array(char, item, -1)
55

56
57
58
#undef TP_STRUCT__entry
#define TP_STRUCT__entry(args...) args

59
60
#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(name, proto, args, tstruct, assign, print)	\
61
62
63
64
	struct ftrace_raw_##name {					\
		struct trace_entry	ent;				\
		tstruct							\
		char			__data[0];			\
65
66
67
68
	};								\
									\
	static struct ftrace_event_class event_class_##name;

69
70
#undef DEFINE_EVENT
#define DEFINE_EVENT(template, name, proto, args)	\
71
72
	static struct ftrace_event_call			\
	__attribute__((__aligned__(4))) event_##name
73

74
75
76
77
#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))

78
79
80
#undef __cpparg
#define __cpparg(arg...) arg

81
82
/* Callbacks are meaningless to ftrace. */
#undef TRACE_EVENT_FN
83
84
85
86
#define TRACE_EVENT_FN(name, proto, args, tstruct,			\
		assign, print, reg, unreg)				\
	TRACE_EVENT(name, __cpparg(proto), __cpparg(args),		\
		__cpparg(tstruct), __cpparg(assign), __cpparg(print))	\
87

88
89
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

90

91
92
93
/*
 * Stage 2 of the trace events.
 *
94
95
 * Include the following:
 *
96
 * struct ftrace_data_offsets_<call> {
97
98
 *	u32				<item1>;
 *	u32				<item2>;
99
100
101
 *	[...]
 * };
 *
102
 * The __dynamic_array() macro will create each u32 <item>, this is
103
 * to keep the offset of each array from the beginning of the event.
104
 * The size of an array is also encoded, in the higher 16 bits of <item>.
105
106
 */

107
#undef __field
108
109
110
111
#define __field(type, item)

#undef __field_ext
#define __field_ext(type, item, filter_type)
112

113
114
115
#undef __array
#define __array(type, item, len)

116
#undef __dynamic_array
117
#define __dynamic_array(type, item, len)	u32 item;
118
119

#undef __string
120
#define __string(item, src) __dynamic_array(char, item, -1)
121

122
123
#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
124
	struct ftrace_data_offsets_##call {				\
125
126
127
		tstruct;						\
	};

128
129
130
#undef DEFINE_EVENT
#define DEFINE_EVENT(template, name, proto, args)

131
132
133
134
#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))

135
136
137
138
139
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

/*
 * Stage 3 of the trace events.
 *
140
141
142
143
144
145
146
147
 * Override the macros in <trace/trace_events.h> to include the following:
 *
 * enum print_line_t
 * ftrace_raw_output_<call>(struct trace_iterator *iter, int flags)
 * {
 *	struct trace_seq *s = &iter->seq;
 *	struct ftrace_raw_<call> *field; <-- defined in stage 1
 *	struct trace_entry *entry;
148
 *	struct trace_seq *p;
149
150
151
152
153
154
155
156
157
158
159
 *	int ret;
 *
 *	entry = iter->ent;
 *
 *	if (entry->type != event_<call>.id) {
 *		WARN_ON_ONCE(1);
 *		return TRACE_TYPE_UNHANDLED;
 *	}
 *
 *	field = (typeof(field))entry;
 *
Li Zefan's avatar
Li Zefan committed
160
 *	p = &get_cpu_var(ftrace_event_seq);
161
 *	trace_seq_init(p);
Li Zefan's avatar
Li Zefan committed
162
163
164
 *	ret = trace_seq_printf(s, "%s: ", <call>);
 *	if (ret)
 *		ret = trace_seq_printf(s, <TP_printk> "\n");
165
 *	put_cpu();
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
 *	if (!ret)
 *		return TRACE_TYPE_PARTIAL_LINE;
 *
 *	return TRACE_TYPE_HANDLED;
 * }
 *
 * This is the method used to print the raw event to the trace
 * output format. Note, this is not needed if the data is read
 * in binary.
 */

#undef __entry
#define __entry field

#undef TP_printk
#define TP_printk(fmt, args...) fmt "\n", args

183
184
#undef __get_dynamic_array
#define __get_dynamic_array(field)	\
185
		((void *)__entry + (__entry->__data_loc_##field & 0xffff))
186

187
#undef __get_str
188
#define __get_str(field) (char *)__get_dynamic_array(field)
189

190
191
192
#undef __print_flags
#define __print_flags(flag, delim, flag_array...)			\
	({								\
193
		static const struct trace_print_flags __flags[] =	\
194
			{ flag_array, { -1, NULL }};			\
195
		ftrace_print_flags_seq(p, delim, flag, __flags);	\
196
197
	})

198
199
200
201
202
203
204
205
#undef __print_symbolic
#define __print_symbolic(value, symbol_array...)			\
	({								\
		static const struct trace_print_flags symbols[] =	\
			{ symbol_array, { -1, NULL }};			\
		ftrace_print_symbols_seq(p, value, symbols);		\
	})

206
207
#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
208
static notrace enum print_line_t					\
209
210
ftrace_raw_output_id_##call(int event_id, const char *name,		\
			    struct trace_iterator *iter, int flags)	\
211
212
213
214
{									\
	struct trace_seq *s = &iter->seq;				\
	struct ftrace_raw_##call *field;				\
	struct trace_entry *entry;					\
215
	struct trace_seq *p;						\
216
217
218
219
	int ret;							\
									\
	entry = iter->ent;						\
									\
220
	if (entry->type != event_id) {					\
221
222
223
224
225
226
		WARN_ON_ONCE(1);					\
		return TRACE_TYPE_UNHANDLED;				\
	}								\
									\
	field = (typeof(field))entry;					\
									\
227
	p = &get_cpu_var(ftrace_event_seq);				\
228
	trace_seq_init(p);						\
229
230
231
	ret = trace_seq_printf(s, "%s: ", name);			\
	if (ret)							\
		ret = trace_seq_printf(s, print);			\
232
	put_cpu();							\
233
234
235
236
237
	if (!ret)							\
		return TRACE_TYPE_PARTIAL_LINE;				\
									\
	return TRACE_TYPE_HANDLED;					\
}
238
239
240

#undef DEFINE_EVENT
#define DEFINE_EVENT(template, name, proto, args)			\
241
static notrace enum print_line_t					\
242
243
ftrace_raw_output_##name(struct trace_iterator *iter, int flags,	\
			 struct trace_event *event)			\
244
245
246
247
248
{									\
	return ftrace_raw_output_id_##template(event_##name.id,		\
					       #name, iter, flags);	\
}

249
250
#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, call, proto, args, print)		\
251
static notrace enum print_line_t					\
252
253
ftrace_raw_output_##call(struct trace_iterator *iter, int flags,	\
			 struct trace_event *event)			\
254
255
256
257
258
{									\
	struct trace_seq *s = &iter->seq;				\
	struct ftrace_raw_##template *field;				\
	struct trace_entry *entry;					\
	struct trace_seq *p;						\
259
260
261
262
263
264
265
266
267
268
269
	int ret;							\
									\
	entry = iter->ent;						\
									\
	if (entry->type != event_##call.id) {				\
		WARN_ON_ONCE(1);					\
		return TRACE_TYPE_UNHANDLED;				\
	}								\
									\
	field = (typeof(field))entry;					\
									\
270
	p = &get_cpu_var(ftrace_event_seq);				\
271
	trace_seq_init(p);						\
272
273
274
	ret = trace_seq_printf(s, "%s: ", #call);			\
	if (ret)							\
		ret = trace_seq_printf(s, print);			\
275
	put_cpu();							\
276
277
278
279
280
	if (!ret)							\
		return TRACE_TYPE_PARTIAL_LINE;				\
									\
	return TRACE_TYPE_HANDLED;					\
}
281

282
283
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

284
285
#undef __field_ext
#define __field_ext(type, item, filter_type)				\
286
287
	ret = trace_define_field(event_call, #type, #item,		\
				 offsetof(typeof(field), item),		\
288
289
				 sizeof(field.item),			\
				 is_signed_type(type), filter_type);	\
290
291
292
	if (ret)							\
		return ret;

293
294
295
#undef __field
#define __field(type, item)	__field_ext(type, item, FILTER_OTHER)

296
297
298
299
300
#undef __array
#define __array(type, item, len)					\
	BUILD_BUG_ON(len > MAX_FILTER_STR_VAL);				\
	ret = trace_define_field(event_call, #type "[" #len "]", #item,	\
				 offsetof(typeof(field), item),		\
301
302
				 sizeof(field.item),			\
				 is_signed_type(type), FILTER_OTHER);	\
303
304
305
	if (ret)							\
		return ret;

306
307
#undef __dynamic_array
#define __dynamic_array(type, item, len)				       \
308
	ret = trace_define_field(event_call, "__data_loc " #type "[]", #item,  \
309
				 offsetof(typeof(field), __data_loc_##item),   \
310
311
				 sizeof(field.__data_loc_##item),	       \
				 is_signed_type(type), FILTER_OTHER);
312

313
#undef __string
314
#define __string(item, src) __dynamic_array(char, item, -1)
315

316
317
#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, func, print)	\
318
static int notrace							\
319
ftrace_define_fields_##call(struct ftrace_event_call *event_call)	\
320
321
322
323
324
325
326
327
328
{									\
	struct ftrace_raw_##call field;					\
	int ret;							\
									\
	tstruct;							\
									\
	return ret;							\
}

329
330
331
#undef DEFINE_EVENT
#define DEFINE_EVENT(template, name, proto, args)

332
333
334
335
#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))

336
337
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

338
339
340
341
342
343
344
345
346
347
/*
 * remember the offset of each array from the beginning of the event.
 */

#undef __entry
#define __entry entry

#undef __field
#define __field(type, item)

348
349
350
#undef __field_ext
#define __field_ext(type, item, filter_type)

351
352
353
354
355
356
357
#undef __array
#define __array(type, item, len)

#undef __dynamic_array
#define __dynamic_array(type, item, len)				\
	__data_offsets->item = __data_size +				\
			       offsetof(typeof(*entry), __data);	\
358
	__data_offsets->item |= (len * sizeof(type)) << 16;		\
359
360
361
	__data_size += (len) * sizeof(type);

#undef __string
362
#define __string(item, src) __dynamic_array(char, item, strlen(src) + 1)
363

364
365
#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
366
static inline notrace int ftrace_get_offsets_##call(			\
367
368
369
370
371
372
373
374
375
376
	struct ftrace_data_offsets_##call *__data_offsets, proto)       \
{									\
	int __data_size = 0;						\
	struct ftrace_raw_##call __maybe_unused *entry;			\
									\
	tstruct;							\
									\
	return __data_size;						\
}

377
378
379
#undef DEFINE_EVENT
#define DEFINE_EVENT(template, name, proto, args)

380
381
382
383
#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))

384
385
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

386
/*
387
 * Stage 4 of the trace events.
388
 *
389
 * Override the macros in <trace/trace_events.h> to include the following:
390
 *
391
 * For those macros defined with TRACE_EVENT:
392
393
394
 *
 * static struct ftrace_event_call event_<call>;
 *
395
 * static void ftrace_raw_event_<call>(void *__data, proto)
396
 * {
397
 *	struct ftrace_event_call *event_call = __data;
Li Zefan's avatar
Li Zefan committed
398
 *	struct ftrace_data_offsets_<call> __maybe_unused __data_offsets;
399
400
 *	struct ring_buffer_event *event;
 *	struct ftrace_raw_<call> *entry; <-- defined in stage 1
401
 *	struct ring_buffer *buffer;
402
 *	unsigned long irq_flags;
Li Zefan's avatar
Li Zefan committed
403
 *	int __data_size;
404
405
406
407
408
 *	int pc;
 *
 *	local_save_flags(irq_flags);
 *	pc = preempt_count();
 *
Li Zefan's avatar
Li Zefan committed
409
410
 *	__data_size = ftrace_get_offsets_<call>(&__data_offsets, args);
 *
411
412
 *	event = trace_current_buffer_lock_reserve(&buffer,
 *				  event_<call>.id,
Li Zefan's avatar
Li Zefan committed
413
 *				  sizeof(*entry) + __data_size,
414
415
416
417
418
 *				  irq_flags, pc);
 *	if (!event)
 *		return;
 *	entry	= ring_buffer_event_data(event);
 *
Li Zefan's avatar
Li Zefan committed
419
420
 *	{ <assign>; }  <-- Here we assign the entries by the __field and
 *			   __array macros.
421
 *
Li Zefan's avatar
Li Zefan committed
422
423
424
 *	if (!filter_current_check_discard(buffer, event_call, entry, event))
 *		trace_current_buffer_unlock_commit(buffer,
 *						   event, irq_flags, pc);
425
426
427
 * }
 *
 * static struct trace_event ftrace_event_type_<call> = {
428
 *	.trace			= ftrace_raw_output_<call>, <-- stage 2
429
430
 * };
 *
Li Zefan's avatar
Li Zefan committed
431
432
 * static const char print_fmt_<call>[] = <TP_printk>;
 *
433
434
 * static struct ftrace_event_class __used event_class_<template> = {
 *	.system			= "<system>",
435
 *	.define_fields		= ftrace_define_fields_<call>,
436
437
438
 *	.fields			= LIST_HEAD_INIT(event_class_##call.fields),
 *	.raw_init		= trace_event_raw_init,
 *	.probe			= ftrace_raw_event_##call,
439
440
 * };
 *
441
442
443
 * static struct ftrace_event_call __used
 * __attribute__((__aligned__(4)))
 * __attribute__((section("_ftrace_events"))) event_<call> = {
444
 *	.name			= "<call>",
445
 *	.class			= event_class_<template>,
446
 *	.event			= &ftrace_event_type_<call>,
Li Zefan's avatar
Li Zefan committed
447
 *	.print_fmt		= print_fmt_<call>,
448
 * };
449
450
451
 *
 */

452
#ifdef CONFIG_PERF_EVENTS
Peter Zijlstra's avatar
Peter Zijlstra committed
453

454
455
456
457
#define _TRACE_PERF_PROTO(call, proto)					\
	static notrace void						\
	perf_trace_##call(void *__data, proto);

458
#define _TRACE_PERF_INIT(call)						\
459
	.perf_probe		= perf_trace_##call,
Peter Zijlstra's avatar
Peter Zijlstra committed
460
461

#else
462
#define _TRACE_PERF_PROTO(call, proto)
463
#define _TRACE_PERF_INIT(call)
464
#endif /* CONFIG_PERF_EVENTS */
Peter Zijlstra's avatar
Peter Zijlstra committed
465

466
467
#undef __entry
#define __entry entry
468

469
470
471
472
473
474
#undef __field
#define __field(type, item)

#undef __array
#define __array(type, item, len)

475
476
477
478
#undef __dynamic_array
#define __dynamic_array(type, item, len)				\
	__entry->__data_loc_##item = __data_offsets.item;

479
#undef __string
480
#define __string(item, src) __dynamic_array(char, item, -1)       	\
481
482
483
484
485

#undef __assign_str
#define __assign_str(dst, src)						\
	strcpy(__get_str(dst), src);

486
487
488
489
490
491
#undef TP_fast_assign
#define TP_fast_assign(args...) args

#undef TP_perf_assign
#define TP_perf_assign(args...)

492
493
#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
494
									\
495
static notrace void							\
496
ftrace_raw_event_##call(void *__data, proto)				\
497
{									\
498
	struct ftrace_event_call *event_call = __data;			\
499
	struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\
500
501
	struct ring_buffer_event *event;				\
	struct ftrace_raw_##call *entry;				\
502
	struct ring_buffer *buffer;					\
503
	unsigned long irq_flags;					\
504
	int __data_size;						\
505
506
507
508
509
	int pc;								\
									\
	local_save_flags(irq_flags);					\
	pc = preempt_count();						\
									\
510
	__data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
511
									\
512
	event = trace_current_buffer_lock_reserve(&buffer,		\
513
				 event_call->id,			\
514
				 sizeof(*entry) + __data_size,		\
515
				 irq_flags, pc);			\
516
517
518
519
	if (!event)							\
		return;							\
	entry	= ring_buffer_event_data(event);			\
									\
520
521
	tstruct								\
									\
522
	{ assign; }							\
523
									\
524
525
526
	if (!filter_current_check_discard(buffer, event_call, entry, event)) \
		trace_nowake_buffer_unlock_commit(buffer,		\
						  event, irq_flags, pc); \
527
}
528
529
530
531
532
/*
 * The ftrace_test_probe is compiled out, it is only here as a build time check
 * to make sure that if the tracepoint handling changes, the ftrace probe will
 * fail to compile unless it too is updated.
 */
533
534
535

#undef DEFINE_EVENT
#define DEFINE_EVENT(template, call, proto, args)			\
536
static struct trace_event_functions ftrace_event_type_funcs_##call = {	\
537
	.trace			= ftrace_raw_output_##call,		\
538
};									\
539
540
541
static struct trace_event ftrace_event_type_##call = {			\
	.funcs			= &ftrace_event_type_funcs_##call,	\
};									\
542
543
544
545
static inline void ftrace_test_probe_##call(void)			\
{									\
	check_trace_callback_type_##call(ftrace_raw_event_##template);	\
}
546
547
548
549
550
551
552

#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

Lai Jiangshan's avatar
Lai Jiangshan committed
553
554
555
556
557
558
559
560
561
562
563
#undef __entry
#define __entry REC

#undef __print_flags
#undef __print_symbolic
#undef __get_dynamic_array
#undef __get_str

#undef TP_printk
#define TP_printk(fmt, args...) "\"" fmt "\", "  __stringify(args)

564
#undef DECLARE_EVENT_CLASS
Lai Jiangshan's avatar
Lai Jiangshan committed
565
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
566
_TRACE_PERF_PROTO(call, PARAMS(proto));					\
567
568
static const char print_fmt_##call[] = print;				\
static struct ftrace_event_class __used event_class_##call = {		\
569
	.system			= __stringify(TRACE_SYSTEM),		\
570
571
	.define_fields		= ftrace_define_fields_##call,		\
	.fields			= LIST_HEAD_INIT(event_class_##call.fields),\
572
	.raw_init		= trace_event_raw_init,			\
573
574
	.probe			= ftrace_raw_event_##call,		\
	_TRACE_PERF_INIT(call)						\
575
};
576
577
578

#undef DEFINE_EVENT
#define DEFINE_EVENT(template, call, proto, args)			\
579
580
581
582
									\
static struct ftrace_event_call __used					\
__attribute__((__aligned__(4)))						\
__attribute__((section("_ftrace_events"))) event_##call = {		\
583
	.name			= #call,				\
584
	.class			= &event_class_##template,		\
585
	.event			= &ftrace_event_type_##call,		\
Lai Jiangshan's avatar
Lai Jiangshan committed
586
	.print_fmt		= print_fmt_##template,			\
587
};
Peter Zijlstra's avatar
Peter Zijlstra committed
588

589
590
#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, call, proto, args, print)		\
591
									\
Lai Jiangshan's avatar
Lai Jiangshan committed
592
593
static const char print_fmt_##call[] = print;				\
									\
594
595
596
static struct ftrace_event_call __used					\
__attribute__((__aligned__(4)))						\
__attribute__((section("_ftrace_events"))) event_##call = {		\
597
	.name			= #call,				\
598
	.class			= &event_class_##template,		\
599
	.event			= &ftrace_event_type_##call,		\
Lai Jiangshan's avatar
Lai Jiangshan committed
600
	.print_fmt		= print_fmt_##call,			\
601
}
Peter Zijlstra's avatar
Peter Zijlstra committed
602

603
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
Peter Zijlstra's avatar
Peter Zijlstra committed
604

605
/*
606
 * Define the insertion callback to perf events
607
608
609
610
 *
 * The job is very similar to ftrace_raw_event_<call> except that we don't
 * insert in the ring buffer but in a perf counter.
 *
611
 * static void ftrace_perf_<call>(proto)
612
613
614
 * {
 *	struct ftrace_data_offsets_<call> __maybe_unused __data_offsets;
 *	struct ftrace_event_call *event_call = &event_<call>;
615
 *	extern void perf_tp_event(int, u64, u64, void *, int);
616
 *	struct ftrace_raw_##call *entry;
617
 *	struct perf_trace_buf *trace_buf;
618
619
 *	u64 __addr = 0, __count = 1;
 *	unsigned long irq_flags;
620
 *	struct trace_entry *ent;
621
622
 *	int __entry_size;
 *	int __data_size;
623
 *	int __cpu
624
625
626
627
628
 *	int pc;
 *
 *	pc = preempt_count();
 *
 *	__data_size = ftrace_get_offsets_<call>(&__data_offsets, args);
629
630
631
632
633
634
 *
 *	// Below we want to get the aligned size by taking into account
 *	// the u32 field that will later store the buffer size
 *	__entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),
 *			     sizeof(u64));
 *	__entry_size -= sizeof(u32);
635
 *
636
637
638
639
640
641
 *	// Protect the non nmi buffer
 *	// This also protects the rcu read side
 *	local_irq_save(irq_flags);
 *	__cpu = smp_processor_id();
 *
 *	if (in_nmi())
642
 *		trace_buf = rcu_dereference_sched(perf_trace_buf_nmi);
643
 *	else
644
 *		trace_buf = rcu_dereference_sched(perf_trace_buf);
645
 *
646
 *	if (!trace_buf)
647
 *		goto end;
648
 *
649
650
651
652
653
654
655
656
657
658
659
660
 *	trace_buf = per_cpu_ptr(trace_buf, __cpu);
 *
 * 	// Avoid recursion from perf that could mess up the buffer
 * 	if (trace_buf->recursion++)
 *		goto end_recursion;
 *
 * 	raw_data = trace_buf->buf;
 *
 *	// Make recursion update visible before entering perf_tp_event
 *	// so that we protect from perf recursions.
 *
 *	barrier();
661
 *
662
663
664
665
666
667
 *	//zero dead bytes from alignment to avoid stack leak to userspace:
 *	*(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL;
 *	entry = (struct ftrace_raw_<call> *)raw_data;
 *	ent = &entry->ent;
 *	tracing_generic_entry_update(ent, irq_flags, pc);
 *	ent->type = event_call->id;
668
 *
669
 *	<tstruct> <- do some jobs with dynamic arrays
670
 *
671
 *	<assign>  <- affect our values
672
 *
673
 *	perf_tp_event(event_call->id, __addr, __count, entry,
674
 *		     __entry_size);  <- submit them to perf counter
675
676
677
678
 *
 * }
 */

679
#ifdef CONFIG_PERF_EVENTS
680

Lai Jiangshan's avatar
Lai Jiangshan committed
681
682
683
684
685
686
687
688
689
690
#undef __entry
#define __entry entry

#undef __get_dynamic_array
#define __get_dynamic_array(field)	\
		((void *)__entry + (__entry->__data_loc_##field & 0xffff))

#undef __get_str
#define __get_str(field) (char *)__get_dynamic_array(field)

691
692
693
694
695
696
#undef __perf_addr
#define __perf_addr(a) __addr = (a)

#undef __perf_count
#define __perf_count(c) __count = (c)

697
698
#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
699
static notrace void							\
700
perf_trace_##call(void *__data, proto)					\
701
{									\
702
	struct ftrace_event_call *event_call = __data;			\
703
704
705
706
	struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\
	struct ftrace_raw_##call *entry;				\
	u64 __addr = 0, __count = 1;					\
	unsigned long irq_flags;					\
707
	struct pt_regs *__regs;						\
708
709
	int __entry_size;						\
	int __data_size;						\
710
	int rctx;							\
711
712
									\
	__data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
713
714
	__entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),\
			     sizeof(u64));				\
715
	__entry_size -= sizeof(u32);					\
716
									\
717
	if (WARN_ONCE(__entry_size > PERF_MAX_TRACE_SIZE,		\
718
719
		      "profile buffer not large enough"))		\
		return;							\
720
	entry = (struct ftrace_raw_##call *)perf_trace_buf_prepare(	\
721
722
723
		__entry_size, event_call->id, &rctx, &irq_flags);	\
	if (!entry)							\
		return;							\
724
725
726
727
	tstruct								\
									\
	{ assign; }							\
									\
728
729
730
	__regs = &__get_cpu_var(perf_trace_regs);			\
	perf_fetch_caller_regs(__regs, 2);				\
									\
731
	perf_trace_buf_submit(entry, __entry_size, rctx, __addr,	\
732
			       __count, irq_flags, __regs);		\
733
734
}

735
736
737
738
739
/*
 * This part is compiled out, it is only here as a build time check
 * to make sure that if the tracepoint handling changes, the
 * perf probe will fail to compile unless it too is updated.
 */
740
#undef DEFINE_EVENT
741
742
743
744
745
#define DEFINE_EVENT(template, call, proto, args)			\
static inline void perf_test_probe_##call(void)				\
{									\
	check_trace_callback_type_##call(perf_trace_##template);	\
									\
746
747
}

748

749
750
751
752
#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))

753
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
754
#endif /* CONFIG_PERF_EVENTS */
755

Peter Zijlstra's avatar
Peter Zijlstra committed
756
757
#undef _TRACE_PROFILE_INIT