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Diffstat (limited to 'include/trace/trace_custom_events.h')
| -rw-r--r-- | include/trace/trace_custom_events.h | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/include/trace/trace_custom_events.h b/include/trace/trace_custom_events.h new file mode 100644 index 000000000..6e492dba9 --- /dev/null +++ b/include/trace/trace_custom_events.h @@ -0,0 +1,221 @@ +/* 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) |