| /* |
| * Copyright (C) 2019 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef INCLUDE_PERFETTO_TRACING_PLATFORM_H_ |
| #define INCLUDE_PERFETTO_TRACING_PLATFORM_H_ |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| |
| #include <functional> |
| #include <memory> |
| #include <string> |
| |
| #include "perfetto/base/export.h" |
| #include "perfetto/base/logging.h" |
| #include "perfetto/base/proc_utils.h" |
| #include "perfetto/tracing/tracing.h" |
| |
| namespace perfetto { |
| |
| namespace base { |
| class TaskRunner; |
| } // namespace base |
| |
| // This abstract class is used to abstract dependencies on platform-specific |
| // primitives that cannot be implemented by the perfetto codebase and must be |
| // provided or overridden by the embedder. |
| // This is, for instance, for cases where we want to use some particular |
| // base:: class in Chrome and provide instead POSIX fallbacks for other |
| // embedders. |
| |
| // Base class for thread-local objects. This is to get a basic object vtable and |
| // delegate destruction to the embedder. See Platform::CreateThreadLocalObject. |
| class PERFETTO_EXPORT PlatformThreadLocalObject { |
| public: |
| // Implemented by perfetto internal code. The embedder must call this when |
| // implementing GetOrCreateThreadLocalObject() to create an instance for the |
| // first time on each thread. |
| static std::unique_ptr<PlatformThreadLocalObject> CreateInstance(); |
| virtual ~PlatformThreadLocalObject(); |
| }; |
| |
| class PERFETTO_EXPORT Platform { |
| public: |
| // Embedders can use this unless they have custom needs (e.g. Chrome wanting |
| // to use its own base class for TLS). |
| static Platform* GetDefaultPlatform(); |
| |
| // Embedders can call this to set process ID in those cases where getpid() |
| // returns incorrect values (e.g. for sandboxed processes in Chromium). |
| // Should only be called once, before tracing has been initialized. |
| static void SetCurrentProcessId(base::PlatformProcessId process_id) { |
| PERFETTO_CHECK(!process_id_); |
| PERFETTO_DCHECK(!Tracing::IsInitialized()); |
| process_id_ = process_id; |
| } |
| |
| // Returns process ID previously set by SetCurrentProcessId, or the process |
| // ID provided by the OS if no custom ID was provided. |
| static base::PlatformProcessId GetCurrentProcessId() { |
| if (process_id_) |
| return process_id_; |
| return base::GetProcessId(); |
| } |
| |
| virtual ~Platform(); |
| |
| // Creates a thread-local object. The embedder must: |
| // - Create an instance per-thread calling ThreadLocalObject::CreateInstance. |
| // - Own the lifetime of the returned object as long as the thread is alive. |
| // - Destroy it when the thread exits. |
| // Perfetto requires only one thread-local object overall (obviously, one |
| // instance per-thread) from the embedder. |
| using ThreadLocalObject = ::perfetto::PlatformThreadLocalObject; |
| virtual ThreadLocalObject* GetOrCreateThreadLocalObject() = 0; |
| |
| // Creates a sequenced task runner. The easiest implementation is to create |
| // a new thread (e.g. use base::ThreadTaskRunner) but this can also be |
| // implemented in some more clever way (e.g. using chromiums's scheduler). |
| struct CreateTaskRunnerArgs { |
| // Optional. Sets the name to the newly created task runner. In the default |
| // PosixPlatform implementation this causes a pthread_setname_np(). This is |
| // only for ease of debugging, it does not affect the tracing behavior. |
| std::string name_for_debugging; |
| }; |
| virtual std::unique_ptr<base::TaskRunner> CreateTaskRunner( |
| const CreateTaskRunnerArgs&) = 0; |
| |
| // Used to derive the producer name. Mostly relevant when using the |
| // kSystemBackend mode. It can be an arbitrary string when using the |
| // in-process mode. |
| virtual std::string GetCurrentProcessName() = 0; |
| |
| private: |
| static base::PlatformProcessId process_id_; |
| }; |
| |
| } // namespace perfetto |
| |
| #endif // INCLUDE_PERFETTO_TRACING_PLATFORM_H_ |