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  1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * Stage 1 of the trace events.
  4 *
  5 * Override the macros in the event tracepoint header <trace/events/XXX.h>
  6 * to include the following:
  7 *
  8 * struct trace_event_raw_<call> {
  9 *	struct trace_entry		ent;
 10 *	<type>				<item>;
 11 *	<type2>				<item2>[<len>];
 12 *	[...]
 13 * };
 14 *
 15 * The <type> <item> is created by the __field(type, item) macro or
 16 * the __array(type2, item2, len) macro.
 17 * We simply do "type item;", and that will create the fields
 18 * in the structure.
 19 */
 20
 21#include <linux/trace_events.h>
 22
 23#ifndef TRACE_SYSTEM_VAR
 24#define TRACE_SYSTEM_VAR TRACE_SYSTEM
 25#endif
 26
 27#include "stages/init.h"
 28
 29/*
 30 * DECLARE_EVENT_CLASS can be used to add a generic function
 31 * handlers for events. That is, if all events have the same
 32 * parameters and just have distinct trace points.
 33 * Each tracepoint can be defined with DEFINE_EVENT and that
 34 * will map the DECLARE_EVENT_CLASS to the tracepoint.
 35 *
 36 * TRACE_EVENT is a one to one mapping between tracepoint and template.
 37 */
 38#undef TRACE_EVENT
 39#define TRACE_EVENT(name, proto, args, tstruct, assign, print) \
 40	DECLARE_EVENT_CLASS(name,			       \
 41			     PARAMS(proto),		       \
 42			     PARAMS(args),		       \
 43			     PARAMS(tstruct),		       \
 44			     PARAMS(assign),		       \
 45			     PARAMS(print));		       \
 46	DEFINE_EVENT(name, name, PARAMS(proto), PARAMS(args));
 47
 48#undef TRACE_EVENT_SYSCALL
 49#define TRACE_EVENT_SYSCALL(name, proto, args, tstruct, assign, print, reg, unreg) \
 50	DECLARE_EVENT_SYSCALL_CLASS(name,		       \
 51			     PARAMS(proto),		       \
 52			     PARAMS(args),		       \
 53			     PARAMS(tstruct),		       \
 54			     PARAMS(assign),		       \
 55			     PARAMS(print));		       \
 56	DEFINE_EVENT(name, name, PARAMS(proto), PARAMS(args));
 57
 58#include "stages/stage1_struct_define.h"
 59
 60#undef DECLARE_EVENT_CLASS
 61#define DECLARE_EVENT_CLASS(name, proto, args, tstruct, assign, print)	\
 62	struct trace_event_raw_##name {					\
 63		struct trace_entry	ent;				\
 64		tstruct							\
 65		char			__data[];			\
 66	};								\
 67									\
 68	static struct trace_event_class event_class_##name;
 69
 70#undef DECLARE_EVENT_SYSCALL_CLASS
 71#define DECLARE_EVENT_SYSCALL_CLASS DECLARE_EVENT_CLASS
 72
 73#undef DEFINE_EVENT
 74#define DEFINE_EVENT(template, name, proto, args)	\
 75	static struct trace_event_call	__used		\
 76	__attribute__((__aligned__(4))) event_##name
 77
 78#undef DEFINE_EVENT_FN
 79#define DEFINE_EVENT_FN(template, name, proto, args, reg, unreg)	\
 80	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))
 81
 82#undef DEFINE_EVENT_PRINT
 83#define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
 84	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))
 85
 86/* Callbacks are meaningless to ftrace. */
 87#undef TRACE_EVENT_FN
 88#define TRACE_EVENT_FN(name, proto, args, tstruct,			\
 89		assign, print, reg, unreg)				\
 90	TRACE_EVENT(name, PARAMS(proto), PARAMS(args),			\
 91		PARAMS(tstruct), PARAMS(assign), PARAMS(print))		\
 92
 93#undef TRACE_EVENT_FN_COND
 94#define TRACE_EVENT_FN_COND(name, proto, args, cond, tstruct,	\
 95		assign, print, reg, unreg)				\
 96	TRACE_EVENT_CONDITION(name, PARAMS(proto), PARAMS(args), PARAMS(cond),		\
 97		PARAMS(tstruct), PARAMS(assign), PARAMS(print))		\
 98
 99#undef TRACE_EVENT_FLAGS
100#define TRACE_EVENT_FLAGS(name, value)					\
101	__TRACE_EVENT_FLAGS(name, value)
102
103#undef TRACE_EVENT_PERF_PERM
104#define TRACE_EVENT_PERF_PERM(name, expr...)				\
105	__TRACE_EVENT_PERF_PERM(name, expr)
106
107#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
108
109/*
110 * Stage 2 of the trace events.
111 *
112 * Include the following:
113 *
114 * struct trace_event_data_offsets_<call> {
115 *	u32				<item1>;
116 *	u32				<item2>;
117 *	[...]
118 * };
119 *
120 * The __dynamic_array() macro will create each u32 <item>, this is
121 * to keep the offset of each array from the beginning of the event.
122 * The size of an array is also encoded, in the higher 16 bits of <item>.
123 */
124
125#include "stages/stage2_data_offsets.h"
126
127#undef DECLARE_EVENT_CLASS
128#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
129	struct trace_event_data_offsets_##call {			\
130		tstruct;						\
131	};
132
133#undef DECLARE_EVENT_SYSCALL_CLASS
134#define DECLARE_EVENT_SYSCALL_CLASS DECLARE_EVENT_CLASS
135
136#undef DEFINE_EVENT
137#define DEFINE_EVENT(template, name, proto, args)
138
139#undef DEFINE_EVENT_PRINT
140#define DEFINE_EVENT_PRINT(template, name, proto, args, print)
141
142#undef TRACE_EVENT_FLAGS
143#define TRACE_EVENT_FLAGS(event, flag)
144
145#undef TRACE_EVENT_PERF_PERM
146#define TRACE_EVENT_PERF_PERM(event, expr...)
147
148#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
149
150/*
151 * Stage 3 of the trace events.
152 *
153 * Override the macros in the event tracepoint header <trace/events/XXX.h>
154 * to include the following:
155 *
156 * enum print_line_t
157 * trace_raw_output_<call>(struct trace_iterator *iter, int flags)
158 * {
159 *	struct trace_seq *s = &iter->seq;
160 *	struct trace_event_raw_<call> *field; <-- defined in stage 1
161 *	struct trace_seq *p = &iter->tmp_seq;
162 *
163 * -------(for event)-------
164 *
165 *	struct trace_entry *entry;
166 *
167 *	entry = iter->ent;
168 *
169 *	if (entry->type != event_<call>->event.type) {
170 *		WARN_ON_ONCE(1);
171 *		return TRACE_TYPE_UNHANDLED;
172 *	}
173 *
174 *	field = (typeof(field))entry;
175 *
176 *	trace_seq_init(p);
177 *	return trace_output_call(iter, <call>, <TP_printk> "\n");
178 *
179 * ------(or, for event class)------
180 *
181 *	int ret;
182 *
183 *	field = (typeof(field))iter->ent;
184 *
185 *	ret = trace_raw_output_prep(iter, trace_event);
186 *	if (ret != TRACE_TYPE_HANDLED)
187 *		return ret;
188 *
189 *	trace_event_printf(iter, <TP_printk> "\n");
190 *
191 *	return trace_handle_return(s);
192 * -------
193 *  }
194 *
195 * This is the method used to print the raw event to the trace
196 * output format. Note, this is not needed if the data is read
197 * in binary.
198 */
199
200#include "stages/stage3_trace_output.h"
201
202#undef DECLARE_EVENT_CLASS
203#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
204static notrace enum print_line_t					\
205trace_raw_output_##call(struct trace_iterator *iter, int flags,		\
206			struct trace_event *trace_event)		\
207{									\
208	struct trace_seq *s = &iter->seq;				\
209	struct trace_seq __maybe_unused *p = &iter->tmp_seq;		\
210	struct trace_event_raw_##call *field;				\
211	int ret;							\
212									\
213	field = (typeof(field))iter->ent;				\
214									\
215	ret = trace_raw_output_prep(iter, trace_event);			\
216	if (ret != TRACE_TYPE_HANDLED)					\
217		return ret;						\
218									\
219	trace_event_printf(iter, print);				\
220									\
221	return trace_handle_return(s);					\
222}									\
223static struct trace_event_functions trace_event_type_funcs_##call = {	\
224	.trace			= trace_raw_output_##call,		\
225};
226
227#undef DECLARE_EVENT_SYSCALL_CLASS
228#define DECLARE_EVENT_SYSCALL_CLASS DECLARE_EVENT_CLASS
229
230#undef DEFINE_EVENT_PRINT
231#define DEFINE_EVENT_PRINT(template, call, proto, args, print)		\
232static notrace enum print_line_t					\
233trace_raw_output_##call(struct trace_iterator *iter, int flags,		\
234			 struct trace_event *event)			\
235{									\
236	struct trace_event_raw_##template *field;			\
237	struct trace_entry *entry;					\
238	struct trace_seq *p = &iter->tmp_seq;				\
239									\
240	entry = iter->ent;						\
241									\
242	if (entry->type != event_##call.event.type) {			\
243		WARN_ON_ONCE(1);					\
244		return TRACE_TYPE_UNHANDLED;				\
245	}								\
246									\
247	field = (typeof(field))entry;					\
248									\
249	trace_seq_init(p);						\
250	return trace_output_call(iter, #call, print);			\
251}									\
252static struct trace_event_functions trace_event_type_funcs_##call = {	\
253	.trace			= trace_raw_output_##call,		\
254};
255
256#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
257
258#include "stages/stage4_event_fields.h"
259
260#undef DECLARE_EVENT_CLASS
261#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, func, print)	\
262static struct trace_event_fields trace_event_fields_##call[] = {	\
263	tstruct								\
264	{} };
265
266#undef DECLARE_EVENT_SYSCALL_CLASS
267#define DECLARE_EVENT_SYSCALL_CLASS DECLARE_EVENT_CLASS
268
269#undef DEFINE_EVENT_PRINT
270#define DEFINE_EVENT_PRINT(template, name, proto, args, print)
271
272#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
273
274#include "stages/stage5_get_offsets.h"
275
276#undef DECLARE_EVENT_CLASS
277#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
278static inline notrace int trace_event_get_offsets_##call(		\
279	struct trace_event_data_offsets_##call *__data_offsets, proto)	\
280{									\
281	int __data_size = 0;						\
282	int __maybe_unused __item_length;				\
283	struct trace_event_raw_##call __maybe_unused *entry;		\
284									\
285	tstruct;							\
286									\
287	return __data_size;						\
288}
289
290#undef DECLARE_EVENT_SYSCALL_CLASS
291#define DECLARE_EVENT_SYSCALL_CLASS DECLARE_EVENT_CLASS
292
293#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
294
295/*
296 * Stage 4 of the trace events.
297 *
298 * Override the macros in the event tracepoint header <trace/events/XXX.h>
299 * to include the following:
300 *
301 * For those macros defined with TRACE_EVENT:
302 *
303 * static struct trace_event_call event_<call>;
304 *
305 * static void trace_event_raw_event_<call>(void *__data, proto)
306 * {
307 *	struct trace_event_file *trace_file = __data;
308 *	struct trace_event_call *event_call = trace_file->event_call;
309 *	struct trace_event_data_offsets_<call> __maybe_unused __data_offsets;
310 *	unsigned long eflags = trace_file->flags;
311 *	enum event_trigger_type __tt = ETT_NONE;
312 *	struct ring_buffer_event *event;
313 *	struct trace_event_raw_<call> *entry; <-- defined in stage 1
314 *	struct trace_buffer *buffer;
315 *	unsigned long irq_flags;
316 *	int __data_size;
317 *	int pc;
318 *
319 *	if (!(eflags & EVENT_FILE_FL_TRIGGER_COND)) {
320 *		if (eflags & EVENT_FILE_FL_TRIGGER_MODE)
321 *			event_triggers_call(trace_file, NULL);
322 *		if (eflags & EVENT_FILE_FL_SOFT_DISABLED)
323 *			return;
324 *	}
325 *
326 *	local_save_flags(irq_flags);
327 *	pc = preempt_count();
328 *
329 *	__data_size = trace_event_get_offsets_<call>(&__data_offsets, args);
330 *
331 *	event = trace_event_buffer_lock_reserve(&buffer, trace_file,
332 *				  event_<call>->event.type,
333 *				  sizeof(*entry) + __data_size,
334 *				  irq_flags, pc);
335 *	if (!event)
336 *		return;
337 *	entry	= ring_buffer_event_data(event);
338 *
339 *	{ <assign>; }  <-- Here we assign the entries by the __field and
340 *			   __array macros.
341 *
342 *	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
343 *		__tt = event_triggers_call(trace_file, entry);
344 *
345 *	if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT,
346 *		     &trace_file->flags))
347 *		ring_buffer_discard_commit(buffer, event);
348 *	else if (!filter_check_discard(trace_file, entry, buffer, event))
349 *		trace_buffer_unlock_commit(buffer, event, irq_flags, pc);
350 *
351 *	if (__tt)
352 *		event_triggers_post_call(trace_file, __tt);
353 * }
354 *
355 * static struct trace_event ftrace_event_type_<call> = {
356 *	.trace			= trace_raw_output_<call>, <-- stage 2
357 * };
358 *
359 * static char print_fmt_<call>[] = <TP_printk>;
360 *
361 * static struct trace_event_class __used event_class_<template> = {
362 *	.system			= "<system>",
363 *	.fields_array		= trace_event_fields_<call>,
364 *	.fields			= LIST_HEAD_INIT(event_class_##call.fields),
365 *	.raw_init		= trace_event_raw_init,
366 *	.probe			= trace_event_raw_event_##call,
367 *	.reg			= trace_event_reg,
368 * };
369 *
370 * static struct trace_event_call event_<call> = {
371 *	.class			= event_class_<template>,
372 *	{
373 *		.tp			= &__tracepoint_<call>,
374 *	},
375 *	.event			= &ftrace_event_type_<call>,
376 *	.print_fmt		= print_fmt_<call>,
377 *	.flags			= TRACE_EVENT_FL_TRACEPOINT,
378 * };
379 * // its only safe to use pointers when doing linker tricks to
380 * // create an array.
381 * static struct trace_event_call __used
382 * __section("_ftrace_events") *__event_<call> = &event_<call>;
383 *
384 */
385
386#ifdef CONFIG_PERF_EVENTS
387
388#define _TRACE_PERF_PROTO(call, proto)					\
389	static notrace void						\
390	perf_trace_##call(void *__data, proto);
391
392#define _TRACE_PERF_INIT(call)						\
393	.perf_probe		= perf_trace_##call,
394
395#else
396#define _TRACE_PERF_PROTO(call, proto)
397#define _TRACE_PERF_INIT(call)
398#endif /* CONFIG_PERF_EVENTS */
399
400#include "stages/stage6_event_callback.h"
401
402
403#undef __DECLARE_EVENT_CLASS
404#define __DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print) \
405static notrace void							\
406do_trace_event_raw_event_##call(void *__data, proto)			\
407{									\
408	struct trace_event_file *trace_file = __data;			\
409	struct trace_event_data_offsets_##call __maybe_unused __data_offsets;\
410	struct trace_event_buffer fbuffer;				\
411	struct trace_event_raw_##call *entry;				\
412	int __data_size;						\
413									\
414	if (trace_trigger_soft_disabled(trace_file))			\
415		return;							\
416									\
417	__data_size = trace_event_get_offsets_##call(&__data_offsets, args); \
418									\
419	entry = trace_event_buffer_reserve(&fbuffer, trace_file,	\
420				 sizeof(*entry) + __data_size);		\
421									\
422	if (!entry)							\
423		return;							\
424									\
425	tstruct								\
426									\
427	{ assign; }							\
428									\
429	trace_event_buffer_commit(&fbuffer);				\
430}
431
432#undef DECLARE_EVENT_CLASS
433#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
434__DECLARE_EVENT_CLASS(call, PARAMS(proto), PARAMS(args), PARAMS(tstruct), \
435		      PARAMS(assign), PARAMS(print))			\
436static notrace void							\
437trace_event_raw_event_##call(void *__data, proto)			\
438{									\
439	do_trace_event_raw_event_##call(__data, args);			\
440}
441
442#undef DECLARE_EVENT_SYSCALL_CLASS
443#define DECLARE_EVENT_SYSCALL_CLASS(call, proto, args, tstruct, assign, print) \
444__DECLARE_EVENT_CLASS(call, PARAMS(proto), PARAMS(args), PARAMS(tstruct), \
445		      PARAMS(assign), PARAMS(print))			\
446static notrace void							\
447trace_event_raw_event_##call(void *__data, proto)			\
448{									\
449	might_fault();							\
450	preempt_disable_notrace();					\
451	do_trace_event_raw_event_##call(__data, args);			\
452	preempt_enable_notrace();					\
453}
454
455/*
456 * The ftrace_test_probe is compiled out, it is only here as a build time check
457 * to make sure that if the tracepoint handling changes, the ftrace probe will
458 * fail to compile unless it too is updated.
459 */
460
461#undef DEFINE_EVENT
462#define DEFINE_EVENT(template, call, proto, args)			\
463static inline void ftrace_test_probe_##call(void)			\
464{									\
465	check_trace_callback_type_##call(trace_event_raw_event_##template); \
466}
467
468#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
469
470#undef __DECLARE_EVENT_CLASS
471
472#include "stages/stage7_class_define.h"
473
474#undef DECLARE_EVENT_CLASS
475#define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
476_TRACE_PERF_PROTO(call, PARAMS(proto));					\
477static char print_fmt_##call[] = print;					\
478static struct trace_event_class __used __refdata event_class_##call = { \
479	.system			= TRACE_SYSTEM_STRING,			\
480	.fields_array		= trace_event_fields_##call,		\
481	.fields			= LIST_HEAD_INIT(event_class_##call.fields),\
482	.raw_init		= trace_event_raw_init,			\
483	.probe			= trace_event_raw_event_##call,		\
484	.reg			= trace_event_reg,			\
485	_TRACE_PERF_INIT(call)						\
486};
487
488#undef DECLARE_EVENT_SYSCALL_CLASS
489#define DECLARE_EVENT_SYSCALL_CLASS DECLARE_EVENT_CLASS
490
491#undef DEFINE_EVENT
492#define DEFINE_EVENT(template, call, proto, args)			\
493									\
494static struct trace_event_call __used event_##call = {			\
495	.class			= &event_class_##template,		\
496	{								\
497		.tp			= &__tracepoint_##call,		\
498	},								\
499	.event.funcs		= &trace_event_type_funcs_##template,	\
500	.print_fmt		= print_fmt_##template,			\
501	.flags			= TRACE_EVENT_FL_TRACEPOINT,		\
502};									\
503static struct trace_event_call __used					\
504__section("_ftrace_events") *__event_##call = &event_##call
505
506#undef DEFINE_EVENT_PRINT
507#define DEFINE_EVENT_PRINT(template, call, proto, args, print)		\
508									\
509static char print_fmt_##call[] = print;					\
510									\
511static struct trace_event_call __used event_##call = {			\
512	.class			= &event_class_##template,		\
513	{								\
514		.tp			= &__tracepoint_##call,		\
515	},								\
516	.event.funcs		= &trace_event_type_funcs_##call,	\
517	.print_fmt		= print_fmt_##call,			\
518	.flags			= TRACE_EVENT_FL_TRACEPOINT,		\
519};									\
520static struct trace_event_call __used					\
521__section("_ftrace_events") *__event_##call = &event_##call
522
523#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)