// Copyright 2019 The Chromium Authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef BASE_TRACE_EVENT_TYPED_MACROS_H_ #define BASE_TRACE_EVENT_TYPED_MACROS_H_ #include "base/trace_event/trace_event.h" #include "base/tracing_buildflags.h" #include "build/build_config.h" // Needed not for this file, but for every user of the TRACE_EVENT macros for // the lambda definition. So included here for convenience. #include "base/tracing/protos/chrome_track_event.pbzero.h" #include "third_party/perfetto/include/perfetto/tracing/event_context.h" #include "third_party/perfetto/include/perfetto/tracing/string_helpers.h" #if !BUILDFLAG(USE_PERFETTO_CLIENT_LIBRARY) #include "base/trace_event/typed_macros_internal.h" #if defined(TRACE_EVENT_BEGIN) #error "Another copy of perfetto tracing macros have been included" #endif // This file implements typed event macros [1,2] that will be provided by the // Perfetto client library in the future, as a stop-gap to support typed trace // events in Chrome until we are ready to switch to the client library's // implementation of trace macros. // [1] https://perfetto.dev/docs/instrumentation/track-events // [2] //third_party/perfetto/include/perfetto/tracing/track_event.h // TODO(crbug/1006541): Replace this file with the Perfetto client library. // Typed event macros: // // These macros emit a slice under |category| with the title |name|. Both // strings must be static constants. The track event is only recorded if // |category| is enabled for the tracing session. // // The slice is thread-scoped (i.e., written to the default track of the current // thread) unless overridden with a custom track object (see perfetto::Track). // // |name| must be a string with static lifetime (i.e., the same address must not // be used for a different event name in the future). If you want to use a // dynamically allocated name, do this: // // TRACE_EVENT("category", nullptr, [&](perfetto::EventContext ctx) { // ctx.event()->set_name(dynamic_name); // }); // // The varargs can include a perfetto::Track (e.g. async events), a // base::TimeTicks timestamp, and a trace lambda. If passed, the lambda is // executed synchronously. // // Examples: // // // Sync event with typed field. // TRACE_EVENT("cat", "Name", [](perfetto::EventContext ctx) { // auto* event = ctx.event(); // // Fill in some field in event. // event->set_my_chrome_field(); // }); // // // Async event. // TRACE_EVENT_BEGIN("cat", "Name", perfetto::Track(1234)); // // // Async event with explicit timestamp. // base::TimeTicks time_ticks; // TRACE_EVENT_BEGIN("cat", "Name", perfetto::Track(1234), time_ticks); // Begin a slice under |category| with the title |name|. // Defaults to the current thread's track. #define TRACE_EVENT_BEGIN(category, name, ...) \ TRACING_INTERNAL_ADD_TRACE_EVENT(TRACE_EVENT_PHASE_BEGIN, category, name, \ ##__VA_ARGS__) // End a slice under |category|. // Defaults to the current thread's track. #define TRACE_EVENT_END(category, ...) \ TRACING_INTERNAL_ADD_TRACE_EVENT(TRACE_EVENT_PHASE_END, category, \ trace_event_internal::kTraceEventEndName, \ ##__VA_ARGS__) // Begin a thread-scoped slice which gets automatically closed when going out // of scope. // // BEWARE: similarly to TRACE_EVENT_BEGIN, this macro does accept a track, but // it does not work properly and should not be used. // TODO(b/154583431): figure out how to fix or disallow that and update the // comment. #define TRACE_EVENT(category, name, ...) \ TRACING_INTERNAL_SCOPED_ADD_TRACE_EVENT(category, name, ##__VA_ARGS__) // Emit a single slice with title |name| and zero duration. // Defaults to the current thread's track. #define TRACE_EVENT_INSTANT(category, name, ...) \ TRACING_INTERNAL_ADD_TRACE_EVENT(TRACE_EVENT_PHASE_INSTANT, category, name, \ ##__VA_ARGS__) #endif // !BUILDFLAG(USE_PERFETTO_CLIENT_LIBRARY) #endif // BASE_TRACE_EVENT_TYPED_MACROS_H_