2 * Stage 1 of the trace events.
4 * Override the macros in <trace/trace_events.h> to include the following:
6 * struct ftrace_raw_<call> {
7 * struct trace_entry ent;
9 * <type2> <item2>[<len>];
13 * The <type> <item> is created by the __field(type, item) macro or
14 * the __array(type2, item2, len) macro.
15 * We simply do "type item;", and that will create the fields
19 #include <linux/ftrace_event.h>
22 #define __field(type, item) type item;
25 #define __array(type, item, len) type item[len];
27 #undef __dynamic_array
28 #define __dynamic_array(type, item, len) u32 __data_loc_##item;
31 #define __string(item, src) __dynamic_array(char, item, -1)
33 #undef TP_STRUCT__entry
34 #define TP_STRUCT__entry(args...) args
37 #define TRACE_EVENT(name, proto, args, tstruct, assign, print) \
38 struct ftrace_raw_##name { \
39 struct trace_entry ent; \
43 static struct ftrace_event_call event_##name
45 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
49 * Stage 2 of the trace events.
51 * Include the following:
53 * struct ftrace_data_offsets_<call> {
59 * The __dynamic_array() macro will create each u32 <item>, this is
60 * to keep the offset of each array from the beginning of the event.
61 * The size of an array is also encoded, in the higher 16 bits of <item>.
65 #define __field(type, item);
68 #define __array(type, item, len)
70 #undef __dynamic_array
71 #define __dynamic_array(type, item, len) u32 item;
74 #define __string(item, src) __dynamic_array(char, item, -1)
77 #define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
78 struct ftrace_data_offsets_##call { \
82 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
85 * Setup the showing format of trace point.
88 * ftrace_format_##call(struct trace_seq *s)
90 * struct ftrace_raw_##call field;
93 * ret = trace_seq_printf(s, #type " " #item ";"
94 * " offset:%u; size:%u;\n",
95 * offsetof(struct ftrace_raw_##call, item),
96 * sizeof(field.type));
101 #undef TP_STRUCT__entry
102 #define TP_STRUCT__entry(args...) args
105 #define __field(type, item) \
106 ret = trace_seq_printf(s, "\tfield:" #type " " #item ";\t" \
107 "offset:%u;\tsize:%u;\n", \
108 (unsigned int)offsetof(typeof(field), item), \
109 (unsigned int)sizeof(field.item)); \
114 #define __array(type, item, len) \
115 ret = trace_seq_printf(s, "\tfield:" #type " " #item "[" #len "];\t" \
116 "offset:%u;\tsize:%u;\n", \
117 (unsigned int)offsetof(typeof(field), item), \
118 (unsigned int)sizeof(field.item)); \
122 #undef __dynamic_array
123 #define __dynamic_array(type, item, len) \
124 ret = trace_seq_printf(s, "\tfield:__data_loc " #type "[] " #item ";\t"\
125 "offset:%u;\tsize:%u;\n", \
126 (unsigned int)offsetof(typeof(field), \
127 __data_loc_##item), \
128 (unsigned int)sizeof(field.__data_loc_##item)); \
133 #define __string(item, src) __dynamic_array(char, item, -1)
138 #undef __print_symbolic
139 #undef __get_dynamic_array
143 #define TP_printk(fmt, args...) "%s, %s\n", #fmt, __stringify(args)
145 #undef TP_fast_assign
146 #define TP_fast_assign(args...) args
148 #undef TP_perf_assign
149 #define TP_perf_assign(args...)
152 #define TRACE_EVENT(call, proto, args, tstruct, func, print) \
154 ftrace_format_##call(struct ftrace_event_call *unused, \
155 struct trace_seq *s) \
157 struct ftrace_raw_##call field __attribute__((unused)); \
162 trace_seq_printf(s, "\nprint fmt: " print); \
167 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
170 * Stage 3 of the trace events.
172 * Override the macros in <trace/trace_events.h> to include the following:
175 * ftrace_raw_output_<call>(struct trace_iterator *iter, int flags)
177 * struct trace_seq *s = &iter->seq;
178 * struct ftrace_raw_<call> *field; <-- defined in stage 1
179 * struct trace_entry *entry;
180 * struct trace_seq *p;
185 * if (entry->type != event_<call>.id) {
187 * return TRACE_TYPE_UNHANDLED;
190 * field = (typeof(field))entry;
192 * p = get_cpu_var(ftrace_event_seq);
194 * ret = trace_seq_printf(s, <TP_printk> "\n");
197 * return TRACE_TYPE_PARTIAL_LINE;
199 * return TRACE_TYPE_HANDLED;
202 * This is the method used to print the raw event to the trace
203 * output format. Note, this is not needed if the data is read
208 #define __entry field
211 #define TP_printk(fmt, args...) fmt "\n", args
213 #undef __get_dynamic_array
214 #define __get_dynamic_array(field) \
215 ((void *)__entry + (__entry->__data_loc_##field & 0xffff))
218 #define __get_str(field) (char *)__get_dynamic_array(field)
221 #define __print_flags(flag, delim, flag_array...) \
223 static const struct trace_print_flags flags[] = \
224 { flag_array, { -1, NULL }}; \
225 ftrace_print_flags_seq(p, delim, flag, flags); \
228 #undef __print_symbolic
229 #define __print_symbolic(value, symbol_array...) \
231 static const struct trace_print_flags symbols[] = \
232 { symbol_array, { -1, NULL }}; \
233 ftrace_print_symbols_seq(p, value, symbols); \
237 #define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
239 ftrace_raw_output_##call(struct trace_iterator *iter, int flags) \
241 struct trace_seq *s = &iter->seq; \
242 struct ftrace_raw_##call *field; \
243 struct trace_entry *entry; \
244 struct trace_seq *p; \
249 if (entry->type != event_##call.id) { \
251 return TRACE_TYPE_UNHANDLED; \
254 field = (typeof(field))entry; \
256 p = &get_cpu_var(ftrace_event_seq); \
258 ret = trace_seq_printf(s, #call ": " print); \
261 return TRACE_TYPE_PARTIAL_LINE; \
263 return TRACE_TYPE_HANDLED; \
266 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
269 #define __field(type, item) \
270 ret = trace_define_field(event_call, #type, #item, \
271 offsetof(typeof(field), item), \
272 sizeof(field.item), is_signed_type(type)); \
277 #define __array(type, item, len) \
278 BUILD_BUG_ON(len > MAX_FILTER_STR_VAL); \
279 ret = trace_define_field(event_call, #type "[" #len "]", #item, \
280 offsetof(typeof(field), item), \
281 sizeof(field.item), 0); \
285 #undef __dynamic_array
286 #define __dynamic_array(type, item, len) \
287 ret = trace_define_field(event_call, "__data_loc " #type "[]", #item, \
288 offsetof(typeof(field), __data_loc_##item), \
289 sizeof(field.__data_loc_##item), 0);
292 #define __string(item, src) __dynamic_array(char, item, -1)
295 #define TRACE_EVENT(call, proto, args, tstruct, func, print) \
297 ftrace_define_fields_##call(void) \
299 struct ftrace_raw_##call field; \
300 struct ftrace_event_call *event_call = &event_##call; \
303 __common_field(int, type, 1); \
304 __common_field(unsigned char, flags, 0); \
305 __common_field(unsigned char, preempt_count, 0); \
306 __common_field(int, pid, 1); \
307 __common_field(int, tgid, 1); \
314 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
317 * remember the offset of each array from the beginning of the event.
321 #define __entry entry
324 #define __field(type, item)
327 #define __array(type, item, len)
329 #undef __dynamic_array
330 #define __dynamic_array(type, item, len) \
331 __data_offsets->item = __data_size + \
332 offsetof(typeof(*entry), __data); \
333 __data_offsets->item |= (len * sizeof(type)) << 16; \
334 __data_size += (len) * sizeof(type);
337 #define __string(item, src) __dynamic_array(char, item, strlen(src) + 1) \
340 #define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
341 static inline int ftrace_get_offsets_##call( \
342 struct ftrace_data_offsets_##call *__data_offsets, proto) \
344 int __data_size = 0; \
345 struct ftrace_raw_##call __maybe_unused *entry; \
349 return __data_size; \
352 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
354 #ifdef CONFIG_EVENT_PROFILE
357 * Generate the functions needed for tracepoint perf_counter support.
359 * NOTE: The insertion profile callback (ftrace_profile_<call>) is defined later
361 * static int ftrace_profile_enable_<call>(struct ftrace_event_call *event_call)
365 * if (!atomic_inc_return(&event_call->profile_count))
366 * ret = register_trace_<call>(ftrace_profile_<call>);
371 * static void ftrace_profile_disable_<call>(struct ftrace_event_call *event_call)
373 * if (atomic_add_negative(-1, &event->call->profile_count))
374 * unregister_trace_<call>(ftrace_profile_<call>);
380 #define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
382 static void ftrace_profile_##call(proto); \
384 static int ftrace_profile_enable_##call(struct ftrace_event_call *event_call) \
388 if (!atomic_inc_return(&event_call->profile_count)) \
389 ret = register_trace_##call(ftrace_profile_##call); \
394 static void ftrace_profile_disable_##call(struct ftrace_event_call *event_call)\
396 if (atomic_add_negative(-1, &event_call->profile_count)) \
397 unregister_trace_##call(ftrace_profile_##call); \
400 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
405 * Stage 4 of the trace events.
407 * Override the macros in <trace/trace_events.h> to include the following:
409 * static void ftrace_event_<call>(proto)
411 * event_trace_printk(_RET_IP_, "<call>: " <fmt>);
414 * static int ftrace_reg_event_<call>(void)
418 * ret = register_trace_<call>(ftrace_event_<call>);
420 * pr_info("event trace: Could not activate trace point "
421 * "probe to <call>");
425 * static void ftrace_unreg_event_<call>(void)
427 * unregister_trace_<call>(ftrace_event_<call>);
431 * For those macros defined with TRACE_EVENT:
433 * static struct ftrace_event_call event_<call>;
435 * static void ftrace_raw_event_<call>(proto)
437 * struct ring_buffer_event *event;
438 * struct ftrace_raw_<call> *entry; <-- defined in stage 1
439 * unsigned long irq_flags;
442 * local_save_flags(irq_flags);
443 * pc = preempt_count();
445 * event = trace_current_buffer_lock_reserve(event_<call>.id,
446 * sizeof(struct ftrace_raw_<call>),
450 * entry = ring_buffer_event_data(event);
452 * <assign>; <-- Here we assign the entries by the __field and
455 * trace_current_buffer_unlock_commit(event, irq_flags, pc);
458 * static int ftrace_raw_reg_event_<call>(void)
462 * ret = register_trace_<call>(ftrace_raw_event_<call>);
464 * pr_info("event trace: Could not activate trace point "
465 * "probe to <call>");
469 * static void ftrace_unreg_event_<call>(void)
471 * unregister_trace_<call>(ftrace_raw_event_<call>);
474 * static struct trace_event ftrace_event_type_<call> = {
475 * .trace = ftrace_raw_output_<call>, <-- stage 2
478 * static int ftrace_raw_init_event_<call>(void)
482 * id = register_ftrace_event(&ftrace_event_type_<call>);
485 * event_<call>.id = id;
489 * static struct ftrace_event_call __used
490 * __attribute__((__aligned__(4)))
491 * __attribute__((section("_ftrace_events"))) event_<call> = {
493 * .system = "<system>",
494 * .raw_init = ftrace_raw_init_event_<call>,
495 * .regfunc = ftrace_reg_event_<call>,
496 * .unregfunc = ftrace_unreg_event_<call>,
497 * .show_format = ftrace_format_<call>,
503 #define TP_FMT(fmt, args...) fmt "\n", ##args
505 #ifdef CONFIG_EVENT_PROFILE
507 #define _TRACE_PROFILE_INIT(call) \
508 .profile_count = ATOMIC_INIT(-1), \
509 .profile_enable = ftrace_profile_enable_##call, \
510 .profile_disable = ftrace_profile_disable_##call,
513 #define _TRACE_PROFILE_INIT(call)
517 #define __entry entry
520 #define __field(type, item)
523 #define __array(type, item, len)
525 #undef __dynamic_array
526 #define __dynamic_array(type, item, len) \
527 __entry->__data_loc_##item = __data_offsets.item;
530 #define __string(item, src) __dynamic_array(char, item, -1) \
533 #define __assign_str(dst, src) \
534 strcpy(__get_str(dst), src);
537 #define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
539 static struct ftrace_event_call event_##call; \
541 static void ftrace_raw_event_##call(proto) \
543 struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\
544 struct ftrace_event_call *event_call = &event_##call; \
545 struct ring_buffer_event *event; \
546 struct ftrace_raw_##call *entry; \
547 unsigned long irq_flags; \
551 local_save_flags(irq_flags); \
552 pc = preempt_count(); \
554 __data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
556 event = trace_current_buffer_lock_reserve(event_##call.id, \
557 sizeof(*entry) + __data_size, \
561 entry = ring_buffer_event_data(event); \
568 if (!filter_current_check_discard(event_call, entry, event)) \
569 trace_nowake_buffer_unlock_commit(event, irq_flags, pc); \
572 static int ftrace_raw_reg_event_##call(void *ptr) \
576 ret = register_trace_##call(ftrace_raw_event_##call); \
578 pr_info("event trace: Could not activate trace point " \
579 "probe to " #call "\n"); \
583 static void ftrace_raw_unreg_event_##call(void *ptr) \
585 unregister_trace_##call(ftrace_raw_event_##call); \
588 static struct trace_event ftrace_event_type_##call = { \
589 .trace = ftrace_raw_output_##call, \
592 static int ftrace_raw_init_event_##call(void) \
596 id = register_ftrace_event(&ftrace_event_type_##call); \
599 event_##call.id = id; \
600 INIT_LIST_HEAD(&event_##call.fields); \
601 init_preds(&event_##call); \
605 static struct ftrace_event_call __used \
606 __attribute__((__aligned__(4))) \
607 __attribute__((section("_ftrace_events"))) event_##call = { \
609 .system = __stringify(TRACE_SYSTEM), \
610 .event = &ftrace_event_type_##call, \
611 .raw_init = ftrace_raw_init_event_##call, \
612 .regfunc = ftrace_raw_reg_event_##call, \
613 .unregfunc = ftrace_raw_unreg_event_##call, \
614 .show_format = ftrace_format_##call, \
615 .define_fields = ftrace_define_fields_##call, \
616 _TRACE_PROFILE_INIT(call) \
619 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
622 * Define the insertion callback to profile events
624 * The job is very similar to ftrace_raw_event_<call> except that we don't
625 * insert in the ring buffer but in a perf counter.
627 * static void ftrace_profile_<call>(proto)
629 * struct ftrace_data_offsets_<call> __maybe_unused __data_offsets;
630 * struct ftrace_event_call *event_call = &event_<call>;
631 * extern void perf_tpcounter_event(int, u64, u64, void *, int);
632 * struct ftrace_raw_##call *entry;
633 * u64 __addr = 0, __count = 1;
634 * unsigned long irq_flags;
639 * local_save_flags(irq_flags);
640 * pc = preempt_count();
642 * __data_size = ftrace_get_offsets_<call>(&__data_offsets, args);
644 * // Below we want to get the aligned size by taking into account
645 * // the u32 field that will later store the buffer size
646 * __entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),
648 * __entry_size -= sizeof(u32);
651 * char raw_data[__entry_size]; <- allocate our sample in the stack
652 * struct trace_entry *ent;
654 * zero dead bytes from alignment to avoid stack leak to userspace:
656 * *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL;
657 * entry = (struct ftrace_raw_<call> *)raw_data;
659 * tracing_generic_entry_update(ent, irq_flags, pc);
660 * ent->type = event_call->id;
662 * <tstruct> <- do some jobs with dynamic arrays
664 * <assign> <- affect our values
666 * perf_tpcounter_event(event_call->id, __addr, __count, entry,
667 * __entry_size); <- submit them to perf counter
673 #ifdef CONFIG_EVENT_PROFILE
676 #define __perf_addr(a) __addr = (a)
679 #define __perf_count(c) __count = (c)
682 #define TRACE_EVENT(call, proto, args, tstruct, assign, print) \
683 static void ftrace_profile_##call(proto) \
685 struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\
686 struct ftrace_event_call *event_call = &event_##call; \
687 extern void perf_tpcounter_event(int, u64, u64, void *, int); \
688 struct ftrace_raw_##call *entry; \
689 u64 __addr = 0, __count = 1; \
690 unsigned long irq_flags; \
695 local_save_flags(irq_flags); \
696 pc = preempt_count(); \
698 __data_size = ftrace_get_offsets_##call(&__data_offsets, args); \
699 __entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),\
701 __entry_size -= sizeof(u32); \
704 char raw_data[__entry_size]; \
705 struct trace_entry *ent; \
707 *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL; \
708 entry = (struct ftrace_raw_##call *)raw_data; \
710 tracing_generic_entry_update(ent, irq_flags, pc); \
711 ent->type = event_call->id; \
717 perf_tpcounter_event(event_call->id, __addr, __count, entry,\
723 #include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
724 #endif /* CONFIG_EVENT_PROFILE */
726 #undef _TRACE_PROFILE_INIT