include/trace/ftrace.h - kernel/msm-4.9 - Gitiles

 /*
  * 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_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_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 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)

 #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 <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 trace_seq *s = &iter->seq;				\
 	struct trace_seq __maybe_unused *p = &iter->tmp_seq;		\
 	struct ftrace_raw_##call *field;				\
 	int ret;							\
 									\
 	field = (typeof(field))iter->ent;				\
 									\
 	ret = ftrace_raw_output_prep(iter, trace_event);		\
 	if (ret)							\
 		return 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 __init						\
 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) ? (const char *)(src) : "(null)") + 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_file *ftrace_file = __data;
  *	struct ftrace_event_call *event_call = ftrace_file->event_call;
  *	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;
  *
  *	if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT,
  *		     &ftrace_file->flags))
  *		return;
  *
  *	local_save_flags(irq_flags);
  *	pc = preempt_count();
  *
  *	__data_size = ftrace_get_offsets_<call>(&__data_offsets, args);
  *
  *	event = trace_event_buffer_lock_reserve(&buffer, ftrace_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 (!filter_check_discard(ftrace_file, entry, buffer, event))
  *		trace_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) ? (const char *)(src) : "(null)");

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

 #undef __perf_addr
 #define __perf_addr(a)	(a)

 #undef __perf_count
 #define __perf_count(c)	(c)

 #undef __perf_task
 #define __perf_task(t)	(t)

 #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_file *ftrace_file = __data;			\
 	struct ftrace_event_call *event_call = ftrace_file->event_call;	\
 	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;								\
 									\
 	if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT,			\
 		     &ftrace_file->flags))				\
 		return;							\
 									\
 	local_save_flags(irq_flags);					\
 	pc = preempt_count();						\
 									\
 	__data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
 									\
 	event = trace_event_buffer_lock_reserve(&buffer, ftrace_file,	\
 				 event_call->event.type,		\
 				 sizeof(*entry) + __data_size,		\
 				 irq_flags, pc);			\
 	if (!event)							\
 		return;							\
 	entry	= ring_buffer_event_data(event);			\
 									\
 	tstruct								\
 									\
 	{ assign; }							\
 									\
 	if (!filter_check_discard(ftrace_file, entry, buffer, event))	\
 		trace_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 __refdata 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)


 #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 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;							\
 									\
 	__data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
 									\
 	head = this_cpu_ptr(event_call->perf_events);			\
 	if (__builtin_constant_p(!__task) && !__task &&			\
 				hlist_empty(head))			\
 		return;							\
 									\
 	__entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),\
 			     sizeof(u64));				\
 	__entry_size -= sizeof(u32);					\
 									\
 	perf_fetch_caller_regs(&__regs);				\
 	entry = perf_trace_buf_prepare(__entry_size,			\
 			event_call->event.type, &__regs, &rctx);	\
 	if (!entry)							\
 		return;							\
 									\
 	tstruct								\
 									\
 	{ assign; }							\
 									\
 	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 */
	/*
	* 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_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_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 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)

	#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 <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 trace_seq *s = &iter->seq; \
	struct trace_seq __maybe_unused *p = &iter->tmp_seq; \
	struct ftrace_raw_##call *field; \
	int ret; \
	\
	field = (typeof(field))iter->ent; \
	\
	ret = ftrace_raw_output_prep(iter, trace_event); \
	if (ret) \
	return 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 __init \
	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) ? (const char *)(src) : "(null)") + 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_file *ftrace_file = __data;
	* struct ftrace_event_call *event_call = ftrace_file->event_call;
	* 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;
	*
	* if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT,
	* &ftrace_file->flags))
	* return;
	*
	* local_save_flags(irq_flags);
	* pc = preempt_count();
	*
	* __data_size = ftrace_get_offsets_<call>(&__data_offsets, args);
	*
	* event = trace_event_buffer_lock_reserve(&buffer, ftrace_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 (!filter_check_discard(ftrace_file, entry, buffer, event))
	* trace_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) ? (const char *)(src) : "(null)");

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

	#undef __perf_addr
	#define __perf_addr(a) (a)

	#undef __perf_count
	#define __perf_count(c) (c)

	#undef __perf_task
	#define __perf_task(t) (t)

	#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_file *ftrace_file = __data; \
	struct ftrace_event_call *event_call = ftrace_file->event_call; \
	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; \
	\
	if (test_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, \
	&ftrace_file->flags)) \
	return; \
	\
	local_save_flags(irq_flags); \
	pc = preempt_count(); \
	\
	__data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
	\
	event = trace_event_buffer_lock_reserve(&buffer, ftrace_file, \
	event_call->event.type, \
	sizeof(*entry) + __data_size, \
	irq_flags, pc); \
	if (!event) \
	return; \
	entry = ring_buffer_event_data(event); \
	\
	tstruct \
	\
	{ assign; } \
	\
	if (!filter_check_discard(ftrace_file, entry, buffer, event)) \
	trace_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 __refdata 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)


	#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 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; \
	\
	__data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
	\
	head = this_cpu_ptr(event_call->perf_events); \
	if (__builtin_constant_p(!__task) && !__task && \
	hlist_empty(head)) \
	return; \
	\
	__entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),\
	sizeof(u64)); \
	__entry_size -= sizeof(u32); \
	\
	perf_fetch_caller_regs(&__regs); \
	entry = perf_trace_buf_prepare(__entry_size, \
	event_call->event.type, &__regs, &rctx); \
	if (!entry) \
	return; \
	\
	tstruct \
	\
	{ assign; } \
	\
	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 */