| // 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 THIRD_PARTY_BLINK_RENDERER_PLATFORM_SCHEDULER_PUBLIC_THREAD_SCHEDULER_H_ |
| #define THIRD_PARTY_BLINK_RENDERER_PLATFORM_SCHEDULER_PUBLIC_THREAD_SCHEDULER_H_ |
| |
| #include <memory> |
| #include "base/location.h" |
| #include "base/single_thread_task_runner.h" |
| #include "base/time/time.h" |
| #include "third_party/blink/public/platform/scheduler/web_main_thread_scheduler.h" |
| #include "third_party/blink/public/platform/web_thread.h" |
| #include "third_party/blink/renderer/platform/scheduler/public/page_scheduler.h" |
| |
| namespace blink { |
| |
| // This class is used to submit tasks and pass other information from Blink to |
| // the platform's scheduler. |
| // TODO(skyostil): Replace this class with WebMainThreadScheduler. |
| class PLATFORM_EXPORT ThreadScheduler { |
| public: |
| using RendererPauseHandle = |
| scheduler::WebMainThreadScheduler::RendererPauseHandle; |
| |
| virtual ~ThreadScheduler() = default; |
| |
| // Called to prevent any more pending tasks from running. Must be called on |
| // the associated WebThread. |
| virtual void Shutdown() = 0; |
| |
| // Returns true if there is high priority work pending on the associated |
| // WebThread and the caller should yield to let the scheduler service that |
| // work. Must be called on the associated WebThread. |
| virtual bool ShouldYieldForHighPriorityWork() = 0; |
| |
| // Returns true if a currently running idle task could exceed its deadline |
| // without impacting user experience too much. This should only be used if |
| // there is a task which cannot be pre-empted and is likely to take longer |
| // than the largest expected idle task deadline. It should NOT be polled to |
| // check whether more work can be performed on the current idle task after |
| // its deadline has expired - post a new idle task for the continuation of |
| // the work in this case. |
| // Must be called from the associated WebThread. |
| virtual bool CanExceedIdleDeadlineIfRequired() const = 0; |
| |
| // Schedule an idle task to run the associated WebThread. For non-critical |
| // tasks which may be reordered relative to other task types and may be |
| // starved for an arbitrarily long time if no idle time is available. |
| // Takes ownership of |IdleTask|. Can be called from any thread. |
| virtual void PostIdleTask(const base::Location&, WebThread::IdleTask) = 0; |
| |
| // Like postIdleTask but guarantees that the posted task will not run |
| // nested within an already-running task. Posting an idle task as |
| // non-nestable may not affect when the task gets run, or it could |
| // make it run later than it normally would, but it won't make it |
| // run earlier than it normally would. |
| virtual void PostNonNestableIdleTask(const base::Location&, |
| WebThread::IdleTask) = 0; |
| |
| // Returns a task runner for kV8 tasks. Can be called from any thread. |
| virtual scoped_refptr<base::SingleThreadTaskRunner> V8TaskRunner() = 0; |
| |
| // Returns a task runner for compositor tasks. This is intended only to be |
| // used by specific animation and rendering related tasks (e.g. animated GIFS) |
| // and should not generally be used. |
| virtual scoped_refptr<base::SingleThreadTaskRunner> |
| CompositorTaskRunner() = 0; |
| |
| // Creates a new PageScheduler for a given Page. Must be called from the |
| // associated WebThread. |
| virtual std::unique_ptr<PageScheduler> CreatePageScheduler( |
| PageScheduler::Delegate*) = 0; |
| |
| // Pauses the scheduler. See WebMainThreadScheduler::PauseRenderer for |
| // details. May only be called from the main thread. |
| virtual std::unique_ptr<RendererPauseHandle> PauseScheduler() |
| WARN_UNUSED_RESULT = 0; |
| |
| // Returns the current time recognized by the scheduler, which may perhaps |
| // be based on a real or virtual time domain. Used by Timer. |
| virtual base::TimeTicks MonotonicallyIncreasingVirtualTime() = 0; |
| |
| // Test helpers. |
| |
| // Return a reference to an underlying WebMainThreadScheduler object. |
| // Can be null if there is no underlying WebMainThreadScheduler |
| // (e.g. worker threads). |
| virtual scheduler::WebMainThreadScheduler* |
| GetWebMainThreadSchedulerForTest() { |
| return nullptr; |
| } |
| }; |
| |
| } // namespace blink |
| |
| #endif // THIRD_PARTY_BLINK_RENDERER_PLATFORM_SCHEDULER_PUBLIC_THREAD_SCHEDULER_H_ |