aboutsummaryrefslogtreecommitdiff
path: root/include/trace/trace_events.h
blob: 8a8cd66cc6d54a036b7485060ddc69d8d32a529a (plain)
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
/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Stage 1 of the trace events.
 *
 * Override the macros in the event tracepoint header <trace/events/XXX.h>
 * to include the following:
 *
 * struct trace_event_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/trace_events.h>

#ifndef TRACE_SYSTEM_VAR
#define TRACE_SYSTEM_VAR TRACE_SYSTEM
#endif

#include "stages/init.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));

#include "stages/stage1_defines.h"

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

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

#undef DEFINE_EVENT_FN
#define DEFINE_EVENT_FN(template, name, proto, args, reg, unreg)	\
	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))

#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_FN_COND
#define TRACE_EVENT_FN_COND(name, proto, args, cond, tstruct,	\
		assign, print, reg, unreg)				\
	TRACE_EVENT_CONDITION(name, PARAMS(proto), PARAMS(args), PARAMS(cond),		\
		PARAMS(tstruct), PARAMS(assign), PARAMS(print))		\

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

#undef TRACE_EVENT_PERF_PERM
#define TRACE_EVENT_PERF_PERM(name, expr...)				\
	__TRACE_EVENT_PERF_PERM(name, expr)

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

/*
 * Stage 2 of the trace events.
 *
 * Include the following:
 *
 * struct trace_event_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>.
 */

#include "stages/stage2_defines.h"

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
	struct trace_event_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)

#undef TRACE_EVENT_FLAGS
#define TRACE_EVENT_FLAGS(event, flag)

#undef TRACE_EVENT_PERF_PERM
#define TRACE_EVENT_PERF_PERM(event, expr...)

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

/*
 * Stage 3 of the trace events.
 *
 * Override the macros in the event tracepoint header <trace/events/XXX.h>
 * to include the following:
 *
 * enum print_line_t
 * trace_raw_output_<call>(struct trace_iterator *iter, int flags)
 * {
 *	struct trace_seq *s = &iter->seq;
 *	struct trace_event_raw_<call> *field; <-- defined in stage 1
 *	struct trace_seq *p = &iter->tmp_seq;
 *
 * -------(for event)-------
 *
 *	struct trace_entry *entry;
 *
 *	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);
 *	return trace_output_call(iter, <call>, <TP_printk> "\n");
 *
 * ------(or, for event class)------
 *
 *	int ret;
 *
 *	field = (typeof(field))iter->ent;
 *
 *	ret = trace_raw_output_prep(iter, trace_event);
 *	if (ret != TRACE_TYPE_HANDLED)
 *		return ret;
 *
 *	trace_event_printf(iter, <TP_printk> "\n");
 *
 *	return trace_handle_return(s);
 * -------
 *  }
 *
 * 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.
 */

#include "stages/stage3_defines.h"

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
static notrace enum print_line_t					\
trace_raw_output_##call(struct trace_iterator *iter, int flags,		\
			struct trace_event *trace_event)		\
{									\
	struct trace_seq *s = &iter->seq;				\
	struct trace_seq __maybe_unused *p = &iter->tmp_seq;		\
	struct trace_event_raw_##call *field;				\
	int ret;							\
									\
	field = (typeof(field))iter->ent;				\
									\
	ret = trace_raw_output_prep(iter, trace_event);			\
	if (ret != TRACE_TYPE_HANDLED)					\
		return ret;						\
									\
	trace_event_printf(iter, print);				\
									\
	return trace_handle_return(s);					\
}									\
static struct trace_event_functions trace_event_type_funcs_##call = {	\
	.trace			= trace_raw_output_##call,		\
};

#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, call, proto, args, print)		\
static notrace enum print_line_t					\
trace_raw_output_##call(struct trace_iterator *iter, int flags,		\
			 struct trace_event *event)			\
{									\
	struct trace_event_raw_##template *field;			\
	struct trace_entry *entry;					\
	struct trace_seq *p = &iter->tmp_seq;				\
									\
	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);						\
	return trace_output_call(iter, #call, print);			\
}									\
static struct trace_event_functions trace_event_type_funcs_##call = {	\
	.trace			= trace_raw_output_##call,		\
};

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

#include "stages/stage4_defines.h"

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, func, print)	\
static struct trace_event_fields trace_event_fields_##call[] = {	\
	tstruct								\
	{} };

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

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

#include "stages/stage5_defines.h"

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

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

/*
 * Stage 4 of the trace events.
 *
 * Override the macros in the event tracepoint header <trace/events/XXX.h>
 * to include the following:
 *
 * For those macros defined with TRACE_EVENT:
 *
 * static struct trace_event_call event_<call>;
 *
 * static void trace_event_raw_event_<call>(void *__data, proto)
 * {
 *	struct trace_event_file *trace_file = __data;
 *	struct trace_event_call *event_call = trace_file->event_call;
 *	struct trace_event_data_offsets_<call> __maybe_unused __data_offsets;
 *	unsigned long eflags = trace_file->flags;
 *	enum event_trigger_type __tt = ETT_NONE;
 *	struct ring_buffer_event *event;
 *	struct trace_event_raw_<call> *entry; <-- defined in stage 1
 *	struct trace_buffer *buffer;
 *	unsigned long irq_flags;
 *	int __data_size;
 *	int pc;
 *
 *	if (!(eflags & EVENT_FILE_FL_TRIGGER_COND)) {
 *		if (eflags & EVENT_FILE_FL_TRIGGER_MODE)
 *			event_triggers_call(trace_file, NULL);
 *		if (eflags & EVENT_FILE_FL_SOFT_DISABLED)
 *			return;
 *	}
 *
 *	local_save_flags(irq_flags);
 *	pc = preempt_count();
 *
 *	__data_size = trace_event_get_offsets_<call>(&__data_offsets, args);
 *
 *	event = trace_event_buffer_lock_reserve(&buffer, trace_file,
 *				  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 (eflags & EVENT_FILE_FL_TRIGGER_COND)
 *		__tt = event_triggers_call(trace_file, entry);
 *
 *	if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT,
 *		     &trace_file->flags))
 *		ring_buffer_discard_commit(buffer, event);
 *	else if (!filter_check_discard(trace_file, entry, buffer, event))
 *		trace_buffer_unlock_commit(buffer, event, irq_flags, pc);
 *
 *	if (__tt)
 *		event_triggers_post_call(trace_file, __tt);
 * }
 *
 * static struct trace_event ftrace_event_type_<call> = {
 *	.trace			= trace_raw_output_<call>, <-- stage 2
 * };
 *
 * static char print_fmt_<call>[] = <TP_printk>;
 *
 * static struct trace_event_class __used event_class_<template> = {
 *	.system			= "<system>",
 *	.fields_array		= trace_event_fields_<call>,
 *	.fields			= LIST_HEAD_INIT(event_class_##call.fields),
 *	.raw_init		= trace_event_raw_init,
 *	.probe			= trace_event_raw_event_##call,
 *	.reg			= trace_event_reg,
 * };
 *
 * static struct trace_event_call event_<call> = {
 *	.class			= event_class_<template>,
 *	{
 *		.tp			= &__tracepoint_<call>,
 *	},
 *	.event			= &ftrace_event_type_<call>,
 *	.print_fmt		= print_fmt_<call>,
 *	.flags			= TRACE_EVENT_FL_TRACEPOINT,
 * };
 * // its only safe to use pointers when doing linker tricks to
 * // create an array.
 * static struct trace_event_call __used
 * __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 */

#include "stages/stage6_defines.h"

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
									\
static notrace void							\
trace_event_raw_event_##call(void *__data, proto)			\
{									\
	struct trace_event_file *trace_file = __data;			\
	struct trace_event_data_offsets_##call __maybe_unused __data_offsets;\
	struct trace_event_buffer fbuffer;				\
	struct trace_event_raw_##call *entry;				\
	int __data_size;						\
									\
	if (trace_trigger_soft_disabled(trace_file))			\
		return;							\
									\
	__data_size = trace_event_get_offsets_##call(&__data_offsets, args); \
									\
	entry = trace_event_buffer_reserve(&fbuffer, trace_file,	\
				 sizeof(*entry) + __data_size);		\
									\
	if (!entry)							\
		return;							\
									\
	tstruct								\
									\
	{ assign; }							\
									\
	trace_event_buffer_commit(&fbuffer);				\
}
/*
 * 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(trace_event_raw_event_##template); \
}

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)

#include "stages/stage7_defines.h"

#undef DECLARE_EVENT_CLASS
#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
_TRACE_PERF_PROTO(call, PARAMS(proto));					\
static char print_fmt_##call[] = print;					\
static struct trace_event_class __used __refdata event_class_##call = { \
	.system			= TRACE_SYSTEM_STRING,			\
	.fields_array		= trace_event_fields_##call,		\
	.fields			= LIST_HEAD_INIT(event_class_##call.fields),\
	.raw_init		= trace_event_raw_init,			\
	.probe			= trace_event_raw_event_##call,		\
	.reg			= trace_event_reg,			\
	_TRACE_PERF_INIT(call)						\
};

#undef DEFINE_EVENT
#define DEFINE_EVENT(template, call, proto, args)			\
									\
static struct trace_event_call __used event_##call = {			\
	.class			= &event_class_##template,		\
	{								\
		.tp			= &__tracepoint_##call,		\
	},								\
	.event.funcs		= &trace_event_type_funcs_##template,	\
	.print_fmt		= print_fmt_##template,			\
	.flags			= TRACE_EVENT_FL_TRACEPOINT,		\
};									\
static struct trace_event_call __used					\
__section("_ftrace_events") *__event_##call = &event_##call

#undef DEFINE_EVENT_PRINT
#define DEFINE_EVENT_PRINT(template, call, proto, args, print)		\
									\
static char print_fmt_##call[] = print;					\
									\
static struct trace_event_call __used event_##call = {			\
	.class			= &event_class_##template,		\
	{								\
		.tp			= &__tracepoint_##call,		\
	},								\
	.event.funcs		= &trace_event_type_funcs_##call,	\
	.print_fmt		= print_fmt_##call,			\
	.flags			= TRACE_EVENT_FL_TRACEPOINT,		\
};									\
static struct trace_event_call __used					\
__section("_ftrace_events") *__event_##call = &event_##call

#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)