| // Copyright 2015 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 MemoryPurgeController_h |
| #define MemoryPurgeController_h |
| |
| #include "platform/PlatformExport.h" |
| #include "platform/heap/Handle.h" |
| #include "wtf/MainThread.h" |
| |
| namespace blink { |
| |
| enum class MemoryPurgeMode { |
| // The tab contains the webview went to background |
| InactiveTab, |
| // TODO(bashi): Add more modes as needed. |
| }; |
| |
| enum class DeviceKind { |
| NotSpecified, |
| LowEnd, |
| }; |
| |
| // Classes which have discardable/reducible memory can implement this |
| // interface to be informed when they should reduce memory consumption. |
| // MemoryPurgeController assumes that subclasses of MemoryPurgeClient are |
| // WillBes. |
| class MemoryPurgeClient : public WillBeGarbageCollectedMixin { |
| public: |
| virtual ~MemoryPurgeClient() { } |
| |
| // MemoryPurgeController invokes this callback when a memory purge event |
| // has occurred. |
| virtual void purgeMemory(MemoryPurgeMode, DeviceKind) = 0; |
| |
| DECLARE_TRACE(); |
| }; |
| |
| // MemoryPurgeController listens to some events which could be opportunities |
| // for reducing memory consumption and notifies its clients. |
| // Since we want to control memory per tab, MemoryPurgeController is owned by |
| // Page. |
| class PLATFORM_EXPORT MemoryPurgeController final : public NoBaseWillBeGarbageCollected<MemoryPurgeController> { |
| DECLARE_EMPTY_DESTRUCTOR_WILL_BE_REMOVED(MemoryPurgeController); |
| public: |
| static PassOwnPtrWillBeRawPtr<MemoryPurgeController> create() |
| { |
| return adoptPtrWillBeNoop(new MemoryPurgeController); |
| } |
| |
| void registerClient(MemoryPurgeClient* client) |
| { |
| ASSERT(isMainThread()); |
| ASSERT(client); |
| ASSERT(!m_clients.contains(client)); |
| m_clients.add(client); |
| } |
| |
| void unregisterClient(MemoryPurgeClient* client) |
| { |
| ASSERT(isMainThread()); |
| ASSERT(m_clients.contains(client)); |
| m_clients.remove(client); |
| } |
| |
| DECLARE_TRACE(); |
| |
| private: |
| MemoryPurgeController(); |
| |
| void purgeMemory(MemoryPurgeMode); |
| |
| WillBeHeapHashSet<RawPtrWillBeWeakMember<MemoryPurgeClient>> m_clients; |
| DeviceKind m_deviceKind; |
| }; |
| |
| } // namespace blink |
| |
| #endif // MemoryPurgeController_h |