/* SPDX-License-Identifier: GPL-2.0 */
/*
* This is similar to the trace_events.h file, but is to only
* create custom trace events to be attached to existing tracepoints.
* Where as the TRACE_EVENT() macro (from trace_events.h) will create
* both the trace event and the tracepoint it will attach the event to,
* TRACE_CUSTOM_EVENT() is to create only a custom version of an existing
* trace event (created by TRACE_EVENT() or DEFINE_EVENT()), and will
* be placed in the "custom" system.
*/
#include <linux/trace_events.h>
/* All custom events are placed in the custom group */
#undef TRACE_SYSTEM
#define TRACE_SYSTEM custom
#ifndef TRACE_SYSTEM_VAR
#define TRACE_SYSTEM_VAR TRACE_SYSTEM
#endif
/* The init stage creates the system string and enum mappings */
#include "stages/init.h"
#undef TRACE_CUSTOM_EVENT
#define TRACE_CUSTOM_EVENT(name, proto, args, tstruct, assign, print) \
DECLARE_CUSTOM_EVENT_CLASS(name, \
PARAMS(proto), \
PARAMS(args), \
PARAMS(tstruct), \
PARAMS(assign), \
PARAMS(print)); \
DEFINE_CUSTOM_EVENT(name, name, PARAMS(proto), PARAMS(args));
/* Stage 1 creates the structure of the recorded event layout */
#include "stages/stage1_struct_define.h"
#undef DECLARE_CUSTOM_EVENT_CLASS
#define DECLARE_CUSTOM_EVENT_CLASS(name, proto, args, tstruct, assign, print) \
struct trace_custom_event_raw_##name { \
struct trace_entry ent; \
tstruct \
char __data[]; \
}; \
\
static struct trace_event_class custom_event_class_##name;
#undef DEFINE_CUSTOM_EVENT
#define DEFINE_CUSTOM_EVENT(template, name, proto, args) \
static struct trace_event_call __used \
__attribute__((__aligned__(4))) custom_event_##name
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
/* Stage 2 creates the custom class */
#include "stages/stage2_data_offsets.h"
#undef DECLARE_CUSTOM_EVENT_CLASS
#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \
struct trace_custom_event_data_offsets_##call { \
tstruct; \
};
#undef DEFINE_CUSTOM_EVENT
#define DEFINE_CUSTOM_EVENT(template, name, proto, args)
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
/* Stage 3 create the way to print the custom event */
#include "stages/stage3_trace_output.h"
#undef DECLARE_CUSTOM_EVENT_CLASS
#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \
static notrace enum print_line_t \
trace_custom_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 trace_custom_event_raw_##call *field; \
int ret; \
\
field = (typeof(field))iter->ent; \
\
ret = trace_raw_output_prep(iter, trace_event); \
if (ret != TRACE_TYPE_HANDLED) \
return ret; \
\
trace_event_printf(iter, print); \
\
return trace_handle_return(s); \
} \
static struct trace_event_functions trace_custom_event_type_funcs_##call = { \
.trace = trace_custom_raw_output_##call, \
};
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
/* Stage 4 creates the offset layout for the fields */
#include "stages/stage4_event_fields.h"
#undef DECLARE_CUSTOM_EVENT_CLASS
#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, func, print) \
static struct trace_event_fields trace_custom_event_fields_##call[] = { \
tstruct \
{} };
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
/* Stage 5 creates the helper function for dynamic fields */
#include "stages/stage5_get_offsets.h"
#undef DECLARE_CUSTOM_EVENT_CLASS
#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \
static inline notrace int trace_custom_event_get_offsets_##call( \
struct trace_custom_event_data_offsets_##call *__data_offsets, proto) \
{ \
int __data_size = 0; \
int __maybe_unused __item_length; \
struct trace_custom_event_raw_##call __maybe_unused *entry; \
\
tstruct; \
\
return __data_size; \
}
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
/* Stage 6 creates the probe function that records the event */
#include "stages/stage6_event_callback.h"
#undef DECLARE_CUSTOM_EVENT_CLASS
#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \
\
static notrace void \
trace_custom_event_raw_event_##call(void *__data, proto) \
{ \
struct trace_event_file *trace_file = __data; \
struct trace_custom_event_data_offsets_##call __maybe_unused __data_offsets; \
struct trace_event_buffer fbuffer; \
struct trace_custom_event_raw_##call *entry; \
int __data_size; \
\
if (trace_trigger_soft_disabled(trace_file)) \
return; \
\
__data_size = trace_custom_event_get_offsets_##call(&__data_offsets, args); \
\
entry = trace_event_buffer_reserve(&fbuffer, trace_file, \
sizeof(*entry) + __data_size); \
\
if (!entry) \
return; \
\
tstruct \
\
{ assign; } \
\
trace_event_buffer_commit(&fbuffer); \
}
/*
* The ftrace_test_custom_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_CUSTOM_EVENT
#define DEFINE_CUSTOM_EVENT(template, call, proto, args) \
static inline void ftrace_test_custom_probe_##call(void) \
{ \
check_trace_callback_type_##call(trace_custom_event_raw_event_##template); \
}
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
/* Stage 7 creates the actual class and event structure for the custom event */
#include "stages/stage7_class_define.h"
#undef DECLARE_CUSTOM_EVENT_CLASS
#define DECLARE_CUSTOM_EVENT_CLASS(call, proto, args, tstruct, assign, print) \
static char custom_print_fmt_##call[] = print; \
static struct trace_event_class __used __refdata custom_event_class_##call = { \
.system = TRACE_SYSTEM_STRING, \
.fields_array = trace_custom_event_fields_##call, \
.fields = LIST_HEAD_INIT(custom_event_class_##call.fields),\
.raw_init = trace_event_raw_init, \
.probe = trace_custom_event_raw_event_##call, \
.reg = trace_event_reg, \
};
#undef DEFINE_CUSTOM_EVENT
#define DEFINE_CUSTOM_EVENT(template, call, proto, args) \
\
static struct trace_event_call __used custom_event_##call = { \
.name = #call, \
.class = &custom_event_class_##template, \
.event.funcs = &trace_custom_event_type_funcs_##template, \
.print_fmt = custom_print_fmt_##template, \
.flags = TRACE_EVENT_FL_CUSTOM, \
}; \
static inline int trace_custom_event_##call##_update(struct tracepoint *tp) \
{ \
if (tp->name && strcmp(tp->name, #call) == 0) { \
custom_event_##call.tp = tp; \
custom_event_##call.flags = TRACE_EVENT_FL_TRACEPOINT; \
return 1; \
} \
return 0; \
} \
static struct trace_event_call __used \
__section("_ftrace_events") *__custom_event_##call = &custom_event_##call
#include TRACE_INCLUDE(TRACE_INCLUDE_FILE)
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