xref: /linux/include/trace/perf.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * Stage 4 of the trace events.
3  *
4  * Override the macros in <trace/trace_events.h> to include the following:
5  *
6  * For those macros defined with TRACE_EVENT:
7  *
8  * static struct trace_event_call event_<call>;
9  *
10  * static void trace_event_raw_event_<call>(void *__data, proto)
11  * {
12  *	struct trace_event_file *trace_file = __data;
13  *	struct trace_event_call *event_call = trace_file->event_call;
14  *	struct trace_event_data_offsets_<call> __maybe_unused __data_offsets;
15  *	unsigned long eflags = trace_file->flags;
16  *	enum event_trigger_type __tt = ETT_NONE;
17  *	struct ring_buffer_event *event;
18  *	struct trace_event_raw_<call> *entry; <-- defined in stage 1
19  *	struct ring_buffer *buffer;
20  *	unsigned long irq_flags;
21  *	int __data_size;
22  *	int pc;
23  *
24  *	if (!(eflags & EVENT_FILE_FL_TRIGGER_COND)) {
25  *		if (eflags & EVENT_FILE_FL_TRIGGER_MODE)
26  *			event_triggers_call(trace_file, NULL);
27  *		if (eflags & EVENT_FILE_FL_SOFT_DISABLED)
28  *			return;
29  *	}
30  *
31  *	local_save_flags(irq_flags);
32  *	pc = preempt_count();
33  *
34  *	__data_size = trace_event_get_offsets_<call>(&__data_offsets, args);
35  *
36  *	event = trace_event_buffer_lock_reserve(&buffer, trace_file,
37  *				  event_<call>->event.type,
38  *				  sizeof(*entry) + __data_size,
39  *				  irq_flags, pc);
40  *	if (!event)
41  *		return;
42  *	entry	= ring_buffer_event_data(event);
43  *
44  *	{ <assign>; }  <-- Here we assign the entries by the __field and
45  *			   __array macros.
46  *
47  *	if (eflags & EVENT_FILE_FL_TRIGGER_COND)
48  *		__tt = event_triggers_call(trace_file, entry);
49  *
50  *	if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT,
51  *		     &trace_file->flags))
52  *		ring_buffer_discard_commit(buffer, event);
53  *	else if (!filter_check_discard(trace_file, entry, buffer, event))
54  *		trace_buffer_unlock_commit(buffer, event, irq_flags, pc);
55  *
56  *	if (__tt)
57  *		event_triggers_post_call(trace_file, __tt);
58  * }
59  *
60  * static struct trace_event ftrace_event_type_<call> = {
61  *	.trace			= trace_raw_output_<call>, <-- stage 2
62  * };
63  *
64  * static char print_fmt_<call>[] = <TP_printk>;
65  *
66  * static struct trace_event_class __used event_class_<template> = {
67  *	.system			= "<system>",
68  *	.define_fields		= trace_event_define_fields_<call>,
69  *	.fields			= LIST_HEAD_INIT(event_class_##call.fields),
70  *	.raw_init		= trace_event_raw_init,
71  *	.probe			= trace_event_raw_event_##call,
72  *	.reg			= trace_event_reg,
73  * };
74  *
75  * static struct trace_event_call event_<call> = {
76  *	.class			= event_class_<template>,
77  *	{
78  *		.tp			= &__tracepoint_<call>,
79  *	},
80  *	.event			= &ftrace_event_type_<call>,
81  *	.print_fmt		= print_fmt_<call>,
82  *	.flags			= TRACE_EVENT_FL_TRACEPOINT,
83  * };
84  * // its only safe to use pointers when doing linker tricks to
85  * // create an array.
86  * static struct trace_event_call __used
87  * __attribute__((section("_ftrace_events"))) *__event_<call> = &event_<call>;
88  *
89  */
90 
91 #ifdef CONFIG_PERF_EVENTS
92 
93 #define _TRACE_PERF_PROTO(call, proto)					\
94 	static notrace void						\
95 	perf_trace_##call(void *__data, proto);
96 
97 #define _TRACE_PERF_INIT(call)						\
98 	.perf_probe		= perf_trace_##call,
99 
100 #else
101 #define _TRACE_PERF_PROTO(call, proto)
102 #define _TRACE_PERF_INIT(call)
103 #endif /* CONFIG_PERF_EVENTS */
104 
105 #undef __entry
106 #define __entry entry
107 
108 #undef __field
109 #define __field(type, item)
110 
111 #undef __field_struct
112 #define __field_struct(type, item)
113 
114 #undef __array
115 #define __array(type, item, len)
116 
117 #undef __dynamic_array
118 #define __dynamic_array(type, item, len)				\
119 	__entry->__data_loc_##item = __data_offsets.item;
120 
121 #undef __string
122 #define __string(item, src) __dynamic_array(char, item, -1)
123 
124 #undef __assign_str
125 #define __assign_str(dst, src)						\
126 	strcpy(__get_str(dst), (src) ? (const char *)(src) : "(null)");
127 
128 #undef __bitmask
129 #define __bitmask(item, nr_bits) __dynamic_array(unsigned long, item, -1)
130 
131 #undef __get_bitmask
132 #define __get_bitmask(field) (char *)__get_dynamic_array(field)
133 
134 #undef __assign_bitmask
135 #define __assign_bitmask(dst, src, nr_bits)					\
136 	memcpy(__get_bitmask(dst), (src), __bitmask_size_in_bytes(nr_bits))
137 
138 #undef TP_fast_assign
139 #define TP_fast_assign(args...) args
140 
141 #undef __perf_addr
142 #define __perf_addr(a)	(a)
143 
144 #undef __perf_count
145 #define __perf_count(c)	(c)
146 
147 #undef __perf_task
148 #define __perf_task(t)	(t)
149 
150 #undef DECLARE_EVENT_CLASS
151 #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
152 									\
153 static notrace void							\
154 trace_event_raw_event_##call(void *__data, proto)			\
155 {									\
156 	struct trace_event_file *trace_file = __data;			\
157 	struct trace_event_data_offsets_##call __maybe_unused __data_offsets;\
158 	struct trace_event_buffer fbuffer;				\
159 	struct trace_event_raw_##call *entry;				\
160 	int __data_size;						\
161 									\
162 	if (trace_trigger_soft_disabled(trace_file))			\
163 		return;							\
164 									\
165 	__data_size = trace_event_get_offsets_##call(&__data_offsets, args); \
166 									\
167 	entry = trace_event_buffer_reserve(&fbuffer, trace_file,	\
168 				 sizeof(*entry) + __data_size);		\
169 									\
170 	if (!entry)							\
171 		return;							\
172 									\
173 	tstruct								\
174 									\
175 	{ assign; }							\
176 									\
177 	trace_event_buffer_commit(&fbuffer);				\
178 }
179 /*
180  * The ftrace_test_probe is compiled out, it is only here as a build time check
181  * to make sure that if the tracepoint handling changes, the ftrace probe will
182  * fail to compile unless it too is updated.
183  */
184 
185 #undef DEFINE_EVENT
186 #define DEFINE_EVENT(template, call, proto, args)			\
187 static inline void ftrace_test_probe_##call(void)			\
188 {									\
189 	check_trace_callback_type_##call(trace_event_raw_event_##template); \
190 }
191 
192 #undef DEFINE_EVENT_PRINT
193 #define DEFINE_EVENT_PRINT(template, name, proto, args, print)
194 
195 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
196 
197 #undef __entry
198 #define __entry REC
199 
200 #undef __print_flags
201 #undef __print_symbolic
202 #undef __print_hex
203 #undef __get_dynamic_array
204 #undef __get_dynamic_array_len
205 #undef __get_str
206 #undef __get_bitmask
207 #undef __print_array
208 
209 #undef TP_printk
210 #define TP_printk(fmt, args...) "\"" fmt "\", "  __stringify(args)
211 
212 #undef DECLARE_EVENT_CLASS
213 #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
214 _TRACE_PERF_PROTO(call, PARAMS(proto));					\
215 static char print_fmt_##call[] = print;					\
216 static struct trace_event_class __used __refdata event_class_##call = { \
217 	.system			= TRACE_SYSTEM_STRING,			\
218 	.define_fields		= trace_event_define_fields_##call,	\
219 	.fields			= LIST_HEAD_INIT(event_class_##call.fields),\
220 	.raw_init		= trace_event_raw_init,			\
221 	.probe			= trace_event_raw_event_##call,		\
222 	.reg			= trace_event_reg,			\
223 	_TRACE_PERF_INIT(call)						\
224 };
225 
226 #undef DEFINE_EVENT
227 #define DEFINE_EVENT(template, call, proto, args)			\
228 									\
229 static struct trace_event_call __used event_##call = {			\
230 	.class			= &event_class_##template,		\
231 	{								\
232 		.tp			= &__tracepoint_##call,		\
233 	},								\
234 	.event.funcs		= &trace_event_type_funcs_##template,	\
235 	.print_fmt		= print_fmt_##template,			\
236 	.flags			= TRACE_EVENT_FL_TRACEPOINT,		\
237 };									\
238 static struct trace_event_call __used					\
239 __attribute__((section("_ftrace_events"))) *__event_##call = &event_##call
240 
241 #undef DEFINE_EVENT_PRINT
242 #define DEFINE_EVENT_PRINT(template, call, proto, args, print)		\
243 									\
244 static char print_fmt_##call[] = print;					\
245 									\
246 static struct trace_event_call __used event_##call = {			\
247 	.class			= &event_class_##template,		\
248 	{								\
249 		.tp			= &__tracepoint_##call,		\
250 	},								\
251 	.event.funcs		= &trace_event_type_funcs_##call,	\
252 	.print_fmt		= print_fmt_##call,			\
253 	.flags			= TRACE_EVENT_FL_TRACEPOINT,		\
254 };									\
255 static struct trace_event_call __used					\
256 __attribute__((section("_ftrace_events"))) *__event_##call = &event_##call
257 
258 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
259 
260 #undef TRACE_SYSTEM_VAR
261 
262 #ifdef CONFIG_PERF_EVENTS
263 
264 #undef __entry
265 #define __entry entry
266 
267 #undef __get_dynamic_array
268 #define __get_dynamic_array(field)	\
269 		((void *)__entry + (__entry->__data_loc_##field & 0xffff))
270 
271 #undef __get_dynamic_array_len
272 #define __get_dynamic_array_len(field)	\
273 		((__entry->__data_loc_##field >> 16) & 0xffff)
274 
275 #undef __get_str
276 #define __get_str(field) (char *)__get_dynamic_array(field)
277 
278 #undef __get_bitmask
279 #define __get_bitmask(field) (char *)__get_dynamic_array(field)
280 
281 #undef __perf_addr
282 #define __perf_addr(a)	(__addr = (a))
283 
284 #undef __perf_count
285 #define __perf_count(c)	(__count = (c))
286 
287 #undef __perf_task
288 #define __perf_task(t)	(__task = (t))
289 
290 #undef DECLARE_EVENT_CLASS
291 #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)	\
292 static notrace void							\
293 perf_trace_##call(void *__data, proto)					\
294 {									\
295 	struct trace_event_call *event_call = __data;			\
296 	struct trace_event_data_offsets_##call __maybe_unused __data_offsets;\
297 	struct trace_event_raw_##call *entry;				\
298 	struct pt_regs *__regs;						\
299 	u64 __addr = 0, __count = 1;					\
300 	struct task_struct *__task = NULL;				\
301 	struct hlist_head *head;					\
302 	int __entry_size;						\
303 	int __data_size;						\
304 	int rctx;							\
305 									\
306 	__data_size = trace_event_get_offsets_##call(&__data_offsets, args); \
307 									\
308 	head = this_cpu_ptr(event_call->perf_events);			\
309 	if (__builtin_constant_p(!__task) && !__task &&			\
310 				hlist_empty(head))			\
311 		return;							\
312 									\
313 	__entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),\
314 			     sizeof(u64));				\
315 	__entry_size -= sizeof(u32);					\
316 									\
317 	entry = perf_trace_buf_prepare(__entry_size,			\
318 			event_call->event.type, &__regs, &rctx);	\
319 	if (!entry)							\
320 		return;							\
321 									\
322 	perf_fetch_caller_regs(__regs);					\
323 									\
324 	tstruct								\
325 									\
326 	{ assign; }							\
327 									\
328 	perf_trace_buf_submit(entry, __entry_size, rctx, __addr,	\
329 		__count, __regs, head, __task);				\
330 }
331 
332 /*
333  * This part is compiled out, it is only here as a build time check
334  * to make sure that if the tracepoint handling changes, the
335  * perf probe will fail to compile unless it too is updated.
336  */
337 #undef DEFINE_EVENT
338 #define DEFINE_EVENT(template, call, proto, args)			\
339 static inline void perf_test_probe_##call(void)				\
340 {									\
341 	check_trace_callback_type_##call(perf_trace_##template);	\
342 }
343 
344 
345 #undef DEFINE_EVENT_PRINT
346 #define DEFINE_EVENT_PRINT(template, name, proto, args, print)	\
347 	DEFINE_EVENT(template, name, PARAMS(proto), PARAMS(args))
348 
349 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
350 #endif /* CONFIG_PERF_EVENTS */
351