aboutsummaryrefslogtreecommitdiffstats
path: root/include/trace/ftrace.h
blob: a763888a36f961339d5a437190c1c944077f875f (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
/*
 * 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>

/*
 * DECLARE_EVENT_CLASS can be used to add a generic function
 * 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
 * will map the DECLARE_EVENT_CLASS to the tracepoint.
 *
 * TRACE_EVENT is a one to one mapping between tracepoint and template.
 */
#undef TRACE_EVENT
#define TRACE_EVENT(name, proto, args, tstruct, assign, print) \
	DECLARE_EVENT_CLASS(name,			       \
			     PARAMS(proto),		       \
			     PARAMS(args),		       \
			     PARAMS(tstruct),		       \
			     PARAMS(assign),		       \
			     PARAMS(print));		       \
	DEFINE_EVENT(name, name, PARAMS(proto), PARAMS(args));


#undef __field
#define __field(type, item)		type	item;

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

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

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

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

#undef TP_STRUCT__entry
#define TP_STRUCT__entry(args...) args

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(name, proto, args, tstruct, assign, print)	\
	struct ftrace_raw_##name {					\
		struct trace_entry	ent;				\
		tstruct							\
		char			__data[0];			\
	};								\
									\
	static struct ftrace_event_class event_class_##name;

#undef DEFINE_EVENT
#define DEFINE_EVENT(template, name, proto, args)	\
	static struct ftrace_event_call	__used		\
	__attribute__((__aligned__(4))) event_##name

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

/* Callbacks are meaningless to ftrace. */
#undef TRACE_EVENT_FN
#define TRACE_EVENT_FN(name, proto, args, tstruct,			\
		assign, print, reg, unreg)				\
	TRACE_EVENT(name, PARAMS(proto), PARAMS(args),			\
		PARAMS(tstruct), PARAMS(assign), PARAMS(print))		\

#undef TRACE_EVENT_FLAGS
#define TRACE_EVENT_FLAGS(name, value)					\
	__TRACE_EVENT_FLAGS(name, value)

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)


/*
 * Stage 2 of the trace events.
 *
 * Include the following:
 *
 * struct ftrace_data_offsets_<call> {
 *	u32				<item1>;
 *	u32				<item2>;
 *	[...]
 * };
 *
 * The __dynamic_array() macro will create each u32 <item>, this is
 * to keep the offset of each array from the beginning of the event.
 * The size of an array is also encoded, in the higher 16 bits of <item>.
 */

#undef __field
#define __field(type, item)

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

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

#undef __dynamic_array
#define __dynamic_array(type, item, len)	u32 item;

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

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
	struct ftrace_data_offsets_##call {				\
		tstruct;						\
	};

#undef DEFINE_EVENT
#define DEFINE_EVENT(template, name, proto, args)

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

#undef TRACE_EVENT_FLAGS
#define TRACE_EVENT_FLAGS(event, flag)

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

/*
 * Stage 3 of the trace events.
 *
 * 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;
 *	struct trace_seq *p = &iter->tmp_seq;
 *	int ret;
 *
 *	entry = iter->ent;
 *
 *	if (entry->type != event_<call>->event.type) {
 *		WARN_ON_ONCE(1);
 *		return TRACE_TYPE_UNHANDLED;
 *	}
 *
 *	field = (typeof(field))entry;
 *
 *	trace_seq_init(p);
 *	ret = trace_seq_printf(s, "%s: ", <call>);
 *	if (ret)
 *		ret = trace_seq_printf(s, <TP_printk> "\n");
 *	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

#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)

#undef __print_flags
#define __print_flags(flag, delim, flag_array...)			\
	({								\
		static const struct trace_print_flags __flags[] =	\
			{ flag_array, { -1, NULL }};			\
		ftrace_print_flags_seq(p, delim, flag, __flags);	\
	})

#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);		\
	})

#undef __print_symbolic_u64
#if BITS_PER_LONG == 32
#define __print_symbolic_u64(value, symbol_array...)			\
	({								\
		static const struct trace_print_flags_u64 symbols[] =	\
			{ symbol_array, { -1, NULL } };			\
		ftrace_print_symbols_seq_u64(p, value, symbols);	\
	})
#else
#define __print_symbolic_u64(value, symbol_array...)			\
			__print_symbolic(value, symbol_array)
#endif

#undef __print_hex
#define __print_hex(buf, buf_len) ftrace_print_hex_seq(p, buf, buf_len)

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
static notrace enum print_line_t					\
ftrace_raw_output_##call(struct trace_iterator *iter, int flags,	\
			 struct trace_event *trace_event)		\
{									\
	struct ftrace_event_call *event;				\
	struct trace_seq *s = &iter->seq;				\
	struct ftrace_raw_##call *field;				\
	struct trace_entry *entry;					\
	struct trace_seq *p = &iter->tmp_seq;				\
	int ret;							\
									\
	event = container_of(trace_event, struct ftrace_event_call,	\
			     event);					\
									\
	entry = iter->ent;						\
									\
	if (entry->type != event->event.type) {				\
		WARN_ON_ONCE(1);					\
		return TRACE_TYPE_UNHANDLED;				\
	}								\
									\
	field = (typeof(field))entry;					\
									\
	trace_seq_init(p);						\
	ret = trace_seq_printf(s, "%s: ", event->name);			\
	if (ret)							\
		ret = trace_seq_printf(s, print);			\
	if (!ret)							\
		return TRACE_TYPE_PARTIAL_LINE;				\
									\
	return TRACE_TYPE_HANDLED;					\
}									\
static struct trace_event_functions ftrace_event_type_funcs_##call = {	\
	.trace			= ftrace_raw_output_##call,		\
};

#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, call, proto, args, print)		\
static notrace enum print_line_t					\
ftrace_raw_output_##call(struct trace_iterator *iter, int flags,	\
			 struct trace_event *event)			\
{									\
	struct trace_seq *s = &iter->seq;				\
	struct ftrace_raw_##template *field;				\
	struct trace_entry *entry;					\
	struct trace_seq *p = &iter->tmp_seq;				\
	int ret;							\
									\
	entry = iter->ent;						\
									\
	if (entry->type != event_##call.event.type) {			\
		WARN_ON_ONCE(1);					\
		return TRACE_TYPE_UNHANDLED;				\
	}								\
									\
	field = (typeof(field))entry;					\
									\
	trace_seq_init(p);						\
	ret = trace_seq_printf(s, "%s: ", #call);			\
	if (ret)							\
		ret = trace_seq_printf(s, print);			\
	if (!ret)							\
		return TRACE_TYPE_PARTIAL_LINE;				\
									\
	return TRACE_TYPE_HANDLED;					\
}									\
static struct trace_event_functions ftrace_event_type_funcs_##call = {	\
	.trace			= ftrace_raw_output_##call,		\
};

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

#undef __field_ext
#define __field_ext(type, item, filter_type)				\
	ret = trace_define_field(event_call, #type, #item,		\
				 offsetof(typeof(field), item),		\
				 sizeof(field.item),			\
				 is_signed_type(type), filter_type);	\
	if (ret)							\
		return ret;

#undef __field
#define __field(type, item)	__field_ext(type, item, FILTER_OTHER)

#undef __array
#define __array(type, item, len)					\
	do {								\
		mutex_lock(&event_storage_mutex);			\
		BUILD_BUG_ON(len > MAX_FILTER_STR_VAL);			\
		snprintf(event_storage, sizeof(event_storage),		\
			 "%s[%d]", #type, len);				\
		ret = trace_define_field(event_call, event_storage, #item, \
				 offsetof(typeof(field), item),		\
				 sizeof(field.item),			\
				 is_signed_type(type), FILTER_OTHER);	\
		mutex_unlock(&event_storage_mutex);			\
		if (ret)						\
			return ret;					\
	} while (0);

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

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

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, func, print)	\
static int notrace							\
ftrace_define_fields_##call(struct ftrace_event_call *event_call)	\
{									\
	struct ftrace_raw_##call field;					\
	int ret;							\
									\
	tstruct;							\
									\
	return ret;							\
}

#undef DEFINE_EVENT
#define DEFINE_EVENT(template, name, proto, args)

#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)

/*
 * remember the offset of each array from the beginning of the event.
 */

#undef __entry
#define __entry entry

#undef __field
#define __field(type, item)

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

#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);	\
	__data_offsets->item |= (len * sizeof(type)) << 16;		\
	__data_size += (len) * sizeof(type);

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

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
static inline notrace int ftrace_get_offsets_##call(			\
	struct ftrace_data_offsets_##call *__data_offsets, proto)       \
{									\
	int __data_size = 0;						\
	struct ftrace_raw_##call __maybe_unused *entry;			\
									\
	tstruct;							\
									\
	return __data_size;						\
}

#undef DEFINE_EVENT
#define DEFINE_EVENT(template, name, proto, args)

#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)

/*
 * Stage 4 of the trace events.
 *
 * Override the macros in <trace/trace_events.h> to include the following:
 *
 * For those macros defined with TRACE_EVENT:
 *
 * static struct ftrace_event_call event_<call>;
 *
 * static void ftrace_raw_event_<call>(void *__data, proto)
 * {
 *	struct ftrace_event_call *event_call = __data;
 *	struct ftrace_data_offsets_<call> __maybe_unused __data_offsets;
 *	struct ring_buffer_event *event;
 *	struct ftrace_raw_<call> *entry; <-- defined in stage 1
 *	struct ring_buffer *buffer;
 *	unsigned long irq_flags;
 *	int __data_size;
 *	int pc;
 *
 *	local_save_flags(irq_flags);
 *	pc = preempt_count();
 *
 *	__data_size = ftrace_get_offsets_<call>(&__data_offsets, args);
 *
 *	event = trace_current_buffer_lock_reserve(&buffer,
 *				  event_<call>->event.type,
 *				  sizeof(*entry) + __data_size,
 *				  irq_flags, pc);
 *	if (!event)
 *		return;
 *	entry	= ring_buffer_event_data(event);
 *
 *	{ <assign>; }  <-- Here we assign the entries by the __field and
 *			   __array macros.
 *
 *	if (!filter_current_check_discard(buffer, event_call, entry, event))
 *		trace_current_buffer_unlock_commit(buffer,
 *						   event, irq_flags, pc);
 * }
 *
 * static struct trace_event ftrace_event_type_<call> = {
 *	.trace			= ftrace_raw_output_<call>, <-- stage 2
 * };
 *
 * static const char print_fmt_<call>[] = <TP_printk>;
 *
 * static struct ftrace_event_class __used event_class_<template> = {
 *	.system			= "<system>",
 *	.define_fields		= ftrace_define_fields_<call>,
 *	.fields			= LIST_HEAD_INIT(event_class_##call.fields),
 *	.raw_init		= trace_event_raw_init,
 *	.probe			= ftrace_raw_event_##call,
 *	.reg			= ftrace_event_reg,
 * };
 *
 * static struct ftrace_event_call event_<call> = {
 *	.name			= "<call>",
 *	.class			= event_class_<template>,
 *	.event			= &ftrace_event_type_<call>,
 *	.print_fmt		= print_fmt_<call>,
 * };
 * // its only safe to use pointers when doing linker tricks to
 * // create an array.
 * static struct ftrace_event_call __used
 * __attribute__((section("_ftrace_events"))) *__event_<call> = &event_<call>;
 *
 */

#ifdef CONFIG_PERF_EVENTS

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

#define _TRACE_PERF_INIT(call)						\
	.perf_probe		= perf_trace_##call,

#else
#define _TRACE_PERF_PROTO(call, proto)
#define _TRACE_PERF_INIT(call)
#endif /* CONFIG_PERF_EVENTS */

#undef __entry
#define __entry entry

#undef __field
#define __field(type, item)

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

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

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

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

#undef TP_fast_assign
#define TP_fast_assign(args...) args

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

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
									\
static notrace void							\
ftrace_raw_event_##call(void *__data, proto)				\
{									\
	struct ftrace_event_call *event_call = __data;			\
	struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\
	struct ring_buffer_event *event;				\
	struct ftrace_raw_##call *entry;				\
	struct ring_buffer *buffer;					\
	unsigned long irq_flags;					\
	int __data_size;						\
	int pc;								\
									\
	local_save_flags(irq_flags);					\
	pc = preempt_count();						\
									\
	__data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
									\
	event = trace_current_buffer_lock_reserve(&buffer,		\
				 event_call->event.type,		\
				 sizeof(*entry) + __data_size,		\
				 irq_flags, pc);			\
	if (!event)							\
		return;							\
	entry	= ring_buffer_event_data(event);			\
									\
	tstruct								\
									\
	{ assign; }							\
									\
	if (!filter_current_check_discard(buffer, event_call, entry, event)) \
		trace_nowake_buffer_unlock_commit(buffer,		\
						  event, irq_flags, pc); \
}
/*
 * 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.
 */

#undef DEFINE_EVENT
#define DEFINE_EVENT(template, call, proto, args)			\
static inline void ftrace_test_probe_##call(void)			\
{									\
	check_trace_callback_type_##call(ftrace_raw_event_##template);	\
}

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

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

#undef __entry
#define __entry REC

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

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

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
_TRACE_PERF_PROTO(call, PARAMS(proto));					\
static const char print_fmt_##call[] = print;				\
static struct ftrace_event_class __used event_class_##call = {		\
	.system			= __stringify(TRACE_SYSTEM),		\
	.define_fields		= ftrace_define_fields_##call,		\
	.fields			= LIST_HEAD_INIT(event_class_##call.fields),\
	.raw_init		= trace_event_raw_init,			\
	.probe			= ftrace_raw_event_##call,		\
	.reg			= ftrace_event_reg,			\
	_TRACE_PERF_INIT(call)						\
};

#undef DEFINE_EVENT
#define DEFINE_EVENT(template, call, proto, args)			\
									\
static struct ftrace_event_call __used event_##call = {			\
	.name			= #call,				\
	.class			= &event_class_##template,		\
	.event.funcs		= &ftrace_event_type_funcs_##template,	\
	.print_fmt		= print_fmt_##template,			\
};									\
static struct ftrace_event_call __used					\
__attribute__((section("_ftrace_events"))) *__event_##call = &event_##call

#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, call, proto, args, print)		\
									\
static const char print_fmt_##call[] = print;				\
									\
static struct ftrace_event_call __used event_##call = {			\
	.name			= #call,				\
	.class			= &event_class_##template,		\
	.event.funcs		= &ftrace_event_type_funcs_##call,	\
	.print_fmt		= print_fmt_##call,			\
};									\
static struct ftrace_event_call __used					\
__attribute__((section("_ftrace_events"))) *__event_##call = &event_##call

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

/*
 * Define the insertion callback to perf events
 *
 * 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.
 *
 * static void ftrace_perf_<call>(proto)
 * {
 *	struct ftrace_data_offsets_<call> __maybe_unused __data_offsets;
 *	struct ftrace_event_call *event_call = &event_<call>;
 *	extern void perf_tp_event(int, u64, u64, void *, int);
 *	struct ftrace_raw_##call *entry;
 *	struct perf_trace_buf *trace_buf;
 *	u64 __addr = 0, __count = 1;
 *	unsigned long irq_flags;
 *	struct trace_entry *ent;
 *	int __entry_size;
 *	int __data_size;
 *	int __cpu
 *	int pc;
 *
 *	pc = preempt_count();
 *
 *	__data_size = ftrace_get_offsets_<call>(&__data_offsets, args);
 *
 *	// 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);
 *
 *	// Protect the non nmi buffer
 *	// This also protects the rcu read side
 *	local_irq_save(irq_flags);
 *	__cpu = smp_processor_id();
 *
 *	if (in_nmi())
 *		trace_buf = rcu_dereference_sched(perf_trace_buf_nmi);
 *	else
 *		trace_buf = rcu_dereference_sched(perf_trace_buf);
 *
 *	if (!trace_buf)
 *		goto end;
 *
 *	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();
 *
 *	//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;
 *
 *	<tstruct> <- do some jobs with dynamic arrays
 *
 *	<assign>  <- affect our values
 *
 *	perf_tp_event(event_call->id, __addr, __count, entry,
 *		     __entry_size);  <- submit them to perf counter
 *
 * }
 */

#ifdef CONFIG_PERF_EVENTS

#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)

#undef __perf_addr
#define __perf_addr(a) __addr = (a)

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

#undef __perf_task
#define __perf_task(t) __task = (t)

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

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
static notrace void							\
perf_trace_##call(void *__data, proto)					\
{									\
	struct ftrace_event_call *event_call = __data;			\
	struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\
	struct ftrace_raw_##call *entry;				\
	struct pt_regs __regs;						\
	u64 __addr = 0, __count = 1;					\
	struct task_struct *__task = NULL;				\
	struct hlist_head *head;					\
	int __entry_size;						\
	int __data_size;						\
	int rctx;							\
									\
	perf_fetch_caller_regs(&__regs);				\
									\
	__data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
	__entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),\
			     sizeof(u64));				\
	__entry_size -= sizeof(u32);					\
									\
	if (WARN_ONCE(__entry_size > PERF_MAX_TRACE_SIZE,		\
		      "profile buffer not large enough"))		\
		return;							\
									\
	entry = (struct ftrace_raw_##call *)perf_trace_buf_prepare(	\
		__entry_size, event_call->event.type, &__regs, &rctx);	\
	if (!entry)							\
		return;							\
									\
	tstruct								\
									\
	{ assign; }							\
									\
	head = this_cpu_ptr(event_call->perf_events);			\
	perf_trace_buf_submit(entry, __entry_size, rctx, __addr,	\
		__count, &__regs, head, __task);			\
}

/*
 * 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.
 */
#undef DEFINE_EVENT
#define DEFINE_EVENT(template, call, proto, args)			\
static inline void perf_test_probe_##call(void)				\
{									\
	check_trace_callback_type_##call(perf_trace_##template);	\
}


#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)
#endif /* CONFIG_PERF_EVENTS */

#undef _TRACE_PROFILE_INIT