kernel/trace/trace_events_stage_2.h

/*
 * Stage 2 of the trace events.
 *
 * Override the macros in <trace/trace_event_types.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;
 *	int ret;
 *
 *	entry = iter->ent;
 *
 *	if (entry->type != event_<call>.id) {
 *		WARN_ON_ONCE(1);
 *		return TRACE_TYPE_UNHANDLED;
 *	}
 *
 *	field = (typeof(field))entry;
 *
 *	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 TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, assign, print)		\
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;				\
	struct trace_entry *entry;					\
	int ret;							\
									\
	entry = iter->ent;						\
									\
	if (entry->type != event_##call.id) {				\
		WARN_ON_ONCE(1);					\
		return TRACE_TYPE_UNHANDLED;				\
	}								\
									\
	field = (typeof(field))entry;					\
									\
	ret = trace_seq_printf(s, #call ": " print);			\
	if (!ret)							\
		return TRACE_TYPE_PARTIAL_LINE;				\
									\
	return TRACE_TYPE_HANDLED;					\
}
	
#include <trace/trace_event_types.h>

/*
 * Setup the showing format of trace point.
 *
 * int
 * ftrace_format_##call(struct trace_seq *s)
 * {
 *	struct ftrace_raw_##call field;
 *	int ret;
 *
 *	ret = trace_seq_printf(s, #type " " #item ";"
 *			       " offset:%u; size:%u;\n",
 *			       offsetof(struct ftrace_raw_##call, item),
 *			       sizeof(field.type));
 *
 * }
 */

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

#undef __field
#define __field(type, item)					\
	ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t"	\
			       "offset:%u;\tsize:%u;\n",		\
			       (unsigned int)offsetof(typeof(field), item), \
			       (unsigned int)sizeof(field.item));	\
	if (!ret)							\
		return 0;

#undef __array
#define __array(type, item, len)						\
	ret = trace_seq_printf(s, "\tfield:" #type " " #item "[" #len "];\t"	\
			       "offset:%u;\tsize:%u;\n",		\
			       (unsigned int)offsetof(typeof(field), item), \
			       (unsigned int)sizeof(field.item));	\
	if (!ret)							\
		return 0;

#undef __entry
#define __entry REC

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

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

#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, func, print)		\
static int								\
ftrace_format_##call(struct trace_seq *s)				\
{									\
	struct ftrace_raw_##call field;					\
	int ret;							\
									\
	tstruct;							\
									\
	trace_seq_printf(s, "\nprint fmt: " print);			\
									\
	return ret;							\
}

#include <trace/trace_event_types.h>

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

#undef __array
#define __array(type, item, len)					\
	ret = trace_define_field(event_call, #type "[" #len "]", #item,	\
				 offsetof(typeof(field), item),		\
				 sizeof(field.item));			\
	if (ret)							\
		return ret;

#define __common_field(type, item)					\
	ret = trace_define_field(event_call, #type, "common_" #item,	\
				 offsetof(typeof(field.ent), item),	\
				 sizeof(field.ent.item));		\
	if (ret)							\
		return ret;

#undef TRACE_EVENT
#define TRACE_EVENT(call, proto, args, tstruct, func, print)		\
int									\
ftrace_define_fields_##call(void)					\
{									\
	struct ftrace_raw_##call field;					\
	struct ftrace_event_call *event_call = &event_##call;		\
	int ret;							\
									\
	__common_field(unsigned char, type);				\
	__common_field(unsigned char, flags);				\
	__common_field(unsigned char, preempt_count);			\
	__common_field(int, pid);					\
	__common_field(int, tgid);					\
									\
	tstruct;							\
									\
	return ret;							\
}

#include <trace/trace_event_types.h>