| // Copyright 2014 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_TASK_COMMON_TASK_ANNOTATOR_H_ |
| #define BASE_TASK_COMMON_TASK_ANNOTATOR_H_ |
| |
| #include <stdint.h> |
| |
| #include <memory> |
| |
| #include "base/base_export.h" |
| #include "base/compiler_specific.h" |
| #include "base/macros.h" |
| #include "base/pending_task.h" |
| |
| namespace base { |
| |
| // Implements common debug annotations for posted tasks. This includes data |
| // such as task origins, IPC message contexts, queueing durations and memory |
| // usage. |
| class BASE_EXPORT TaskAnnotator { |
| public: |
| class ObserverForTesting { |
| public: |
| // Invoked just before RunTask() in the scope in which the task is about to |
| // be executed. |
| virtual void BeforeRunTask(const PendingTask* pending_task) = 0; |
| }; |
| |
| // This is used to set the |ipc_hash| field for PendingTasks. It is intended |
| // to be used only from within generated IPC handler dispatch code. |
| class ScopedSetIpcHash; |
| |
| static const PendingTask* CurrentTaskForThread(); |
| |
| TaskAnnotator(); |
| ~TaskAnnotator(); |
| |
| // Called to indicate that a task is about to be queued to run in the future, |
| // giving one last chance for this TaskAnnotator to add metadata to |
| // |pending_task| before it is moved into the queue. |task_queue_name| must |
| // live for the duration of the process. |
| void WillQueueTask(const char* trace_event_name, |
| PendingTask* pending_task, |
| const char* task_queue_name); |
| |
| // Run a previously queued task. |
| void NOT_TAIL_CALLED RunTask(const char* trace_event_name, |
| PendingTask* pending_task); |
| |
| // Creates a process-wide unique ID to represent this task in trace events. |
| // This will be mangled with a Process ID hash to reduce the likelyhood of |
| // colliding with TaskAnnotator pointers on other processes. Callers may use |
| // this when generating their own flow events (i.e. when passing |
| // |queue_function == nullptr| in above methods). |
| uint64_t GetTaskTraceID(const PendingTask& task) const; |
| |
| private: |
| friend class TaskAnnotatorBacktraceIntegrationTest; |
| |
| // Registers an ObserverForTesting that will be invoked by all TaskAnnotators' |
| // RunTask(). This registration and the implementation of BeforeRunTask() are |
| // responsible to ensure thread-safety. |
| static void RegisterObserverForTesting(ObserverForTesting* observer); |
| static void ClearObserverForTesting(); |
| |
| DISALLOW_COPY_AND_ASSIGN(TaskAnnotator); |
| }; |
| |
| class BASE_EXPORT TaskAnnotator::ScopedSetIpcHash { |
| public: |
| explicit ScopedSetIpcHash(uint32_t ipc_hash); |
| ~ScopedSetIpcHash(); |
| |
| private: |
| std::unique_ptr<PendingTask> dummy_pending_task_; |
| uint32_t old_ipc_hash_ = 0; |
| |
| DISALLOW_COPY_AND_ASSIGN(ScopedSetIpcHash); |
| }; |
| |
| } // namespace base |
| |
| #endif // BASE_TASK_COMMON_TASK_ANNOTATOR_H_ |