1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * This is similar to the trace_events.h file, but is to only
4 * create custom trace events to be attached to existing tracepoints.
5 * Where as the TRACE_EVENT() macro (from trace_events.h) will create
6 * both the trace event and the tracepoint it will attach the event to,
7 * TRACE_CUSTOM_EVENT() is to create only a custom version of an existing
8 * trace event (created by TRACE_EVENT() or DEFINE_EVENT()), and will
9 * be placed in the "custom" system.
10 */
11
12#include <linux/trace_events.h>
13
14/* All custom events are placed in the custom group */
15#undef TRACE_SYSTEM
16#define TRACE_SYSTEM custom
17
18#ifndef TRACE_SYSTEM_VAR
19#define TRACE_SYSTEM_VAR TRACE_SYSTEM
20#endif
21
22/* The init stage creates the system string and enum mappings */
23
24#include "stages/init.h"
25
26#undef TRACE_CUSTOM_EVENT
27#define TRACE_CUSTOM_EVENT(name, proto, args, tstruct, assign, print) \
28	DECLARE_CUSTOM_EVENT_CLASS(name,			      \
29			     PARAMS(proto),		       \
30			     PARAMS(args),		       \
31			     PARAMS(tstruct),		       \
32			     PARAMS(assign),		       \
33			     PARAMS(print));		       \
34	DEFINE_CUSTOM_EVENT(name, name, PARAMS(proto), PARAMS(args));
35
36/* Stage 1 creates the structure of the recorded event layout */
37
38#include "stages/stage1_struct_define.h"
39
40#undef DECLARE_CUSTOM_EVENT_CLASS
41#define DECLARE_CUSTOM_EVENT_CLASS(name, proto, args, tstruct, assign, print) \
42	struct trace_custom_event_raw_##name {				\
43		struct trace_entry	ent;				\
44		tstruct							\
45		char			__data[];			\
46	};								\
47									\
48	static struct trace_event_class custom_event_class_##name;
49
50#undef DEFINE_CUSTOM_EVENT
51#define DEFINE_CUSTOM_EVENT(template, name, proto, args)	\
52	static struct trace_event_call	__used			\
53	__attribute__((__aligned__(4))) custom_event_##name
54
55#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
56
57/* Stage 2 creates the custom class */
58
59#include "stages/stage2_data_offsets.h"
60
61#undef DECLARE_CUSTOM_EVENT_CLASS
62#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
63	struct trace_custom_event_data_offsets_##call {			\
64		tstruct;						\
65	};
66
67#undef DEFINE_CUSTOM_EVENT
68#define DEFINE_CUSTOM_EVENT(template, name, proto, args)
69
70#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
71
72/* Stage 3 create the way to print the custom event */
73
74#include "stages/stage3_trace_output.h"
75
76#undef DECLARE_CUSTOM_EVENT_CLASS
77#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \
78static notrace enum print_line_t					\
79trace_custom_raw_output_##call(struct trace_iterator *iter, int flags,	\
80			struct trace_event *trace_event)		\
81{									\
82	struct trace_seq *s = &iter->seq;				\
83	struct trace_seq __maybe_unused *p = &iter->tmp_seq;		\
84	struct trace_custom_event_raw_##call *field;			\
85	int ret;							\
86									\
87	field = (typeof(field))iter->ent;				\
88									\
89	ret = trace_raw_output_prep(iter, trace_event);			\
90	if (ret != TRACE_TYPE_HANDLED)					\
91		return ret;						\
92									\
93	trace_event_printf(iter, print);				\
94									\
95	return trace_handle_return(s);					\
96}									\
97static struct trace_event_functions trace_custom_event_type_funcs_##call = { \
98	.trace			= trace_custom_raw_output_##call,	\
99};
100
101#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
102
103/* Stage 4 creates the offset layout for the fields */
104
105#include "stages/stage4_event_fields.h"
106
107#undef DECLARE_CUSTOM_EVENT_CLASS
108#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, func, print)	\
109static struct trace_event_fields trace_custom_event_fields_##call[] = {	\
110	tstruct								\
111	{} };
112
113#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
114
115/* Stage 5 creates the helper function for dynamic fields */
116
117#include "stages/stage5_get_offsets.h"
118
119#undef DECLARE_CUSTOM_EVENT_CLASS
120#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \
121static inline notrace int trace_custom_event_get_offsets_##call(	\
122	struct trace_custom_event_data_offsets_##call *__data_offsets, proto) \
123{									\
124	int __data_size = 0;						\
125	int __maybe_unused __item_length;				\
126	struct trace_custom_event_raw_##call __maybe_unused *entry;	\
127									\
128	tstruct;							\
129									\
130	return __data_size;						\
131}
132
133#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
134
135/* Stage 6 creates the probe function that records the event */
136
137#include "stages/stage6_event_callback.h"
138
139#undef DECLARE_CUSTOM_EVENT_CLASS
140#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \
141									\
142static notrace void							\
143trace_custom_event_raw_event_##call(void *__data, proto)		\
144{									\
145	struct trace_event_file *trace_file = __data;			\
146	struct trace_custom_event_data_offsets_##call __maybe_unused __data_offsets; \
147	struct trace_event_buffer fbuffer;				\
148	struct trace_custom_event_raw_##call *entry;			\
149	int __data_size;						\
150									\
151	if (trace_trigger_soft_disabled(trace_file))			\
152		return;							\
153									\
154	__data_size = trace_custom_event_get_offsets_##call(&__data_offsets, args); \
155									\
156	entry = trace_event_buffer_reserve(&fbuffer, trace_file,	\
157				 sizeof(*entry) + __data_size);		\
158									\
159	if (!entry)							\
160		return;							\
161									\
162	tstruct								\
163									\
164	{ assign; }							\
165									\
166	trace_event_buffer_commit(&fbuffer);				\
167}
168/*
169 * The ftrace_test_custom_probe is compiled out, it is only here as a build time check
170 * to make sure that if the tracepoint handling changes, the ftrace probe will
171 * fail to compile unless it too is updated.
172 */
173
174#undef DEFINE_CUSTOM_EVENT
175#define DEFINE_CUSTOM_EVENT(template, call, proto, args)		\
176static inline void ftrace_test_custom_probe_##call(void)		\
177{									\
178	check_trace_callback_type_##call(trace_custom_event_raw_event_##template); \
179}
180
181#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
182
183/* Stage 7 creates the actual class and event structure for the custom event */
184
185#include "stages/stage7_class_define.h"
186
187#undef DECLARE_CUSTOM_EVENT_CLASS
188#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \
189static char custom_print_fmt_##call[] = print;					\
190static struct trace_event_class __used __refdata custom_event_class_##call = { \
191	.system			= TRACE_SYSTEM_STRING,			\
192	.fields_array		= trace_custom_event_fields_##call,		\
193	.fields			= LIST_HEAD_INIT(custom_event_class_##call.fields),\
194	.raw_init		= trace_event_raw_init,			\
195	.probe			= trace_custom_event_raw_event_##call,	\
196	.reg			= trace_event_reg,			\
197};
198
199#undef DEFINE_CUSTOM_EVENT
200#define DEFINE_CUSTOM_EVENT(template, call, proto, args)		\
201									\
202static struct trace_event_call __used custom_event_##call = {		\
203	.name			= #call,				\
204	.class			= &custom_event_class_##template,	\
205	.event.funcs		= &trace_custom_event_type_funcs_##template, \
206	.print_fmt		= custom_print_fmt_##template,		\
207	.flags			= TRACE_EVENT_FL_CUSTOM,		\
208};									\
209static inline int trace_custom_event_##call##_update(struct tracepoint *tp) \
210{									\
211	if (tp->name && strcmp(tp->name, #call) == 0) {			\
212		custom_event_##call.tp = tp;				\
213		custom_event_##call.flags = TRACE_EVENT_FL_TRACEPOINT;	\
214		return 1;						\
215	}								\
216	return 0;							\
217}									\
218static struct trace_event_call __used					\
219__section("_ftrace_events") *__custom_event_##call = &custom_event_##call
220
221#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
222