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Diffstat (limited to 'services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/TexturePool.h')
-rw-r--r-- | services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/TexturePool.h | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/TexturePool.h b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/TexturePool.h new file mode 100644 index 0000000000..fb53ee04cd --- /dev/null +++ b/services/surfaceflinger/CompositionEngine/include/compositionengine/impl/planner/TexturePool.h @@ -0,0 +1,102 @@ +/* + * Copyright 2021 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. + */ + +#pragma once + +#include <compositionengine/Output.h> +#include <compositionengine/ProjectionSpace.h> +#include <compositionengine/impl/planner/LayerState.h> +#include <renderengine/RenderEngine.h> + +#include <renderengine/ExternalTexture.h> +#include <chrono> +#include "android-base/macros.h" + +namespace android::compositionengine::impl::planner { + +// A pool of textures that only manages textures of a single size. +// While it is possible to define a texture pool supporting variable-sized textures to save on +// memory, it is a simpler implementation to only manage screen-sized textures. The texture pool is +// unbounded - there are a minimum number of textures preallocated. Under heavy system load, new +// textures may be allocated, but only a maximum number of retained once those textures are no +// longer necessary. +class TexturePool { +public: + // RAII class helping with managing textures from the texture pool + // Textures once they're no longer used should be returned to the pool instead of outright + // deleted. + class AutoTexture { + public: + AutoTexture(TexturePool& texturePool, + std::shared_ptr<renderengine::ExternalTexture> texture, const sp<Fence>& fence) + : mTexturePool(texturePool), mTexture(texture), mFence(fence) {} + + ~AutoTexture() { mTexturePool.returnTexture(std::move(mTexture), mFence); } + + sp<Fence> getReadyFence() { return mFence; } + + void setReadyFence(const sp<Fence>& fence) { mFence = fence; } + + // Disable copying and assigning + AutoTexture(const AutoTexture&) = delete; + AutoTexture& operator=(const AutoTexture&) = delete; + + // Gets a pointer to the underlying external texture + const std::shared_ptr<renderengine::ExternalTexture>& get() const { return mTexture; } + + private: + TexturePool& mTexturePool; + std::shared_ptr<renderengine::ExternalTexture> mTexture; + sp<Fence> mFence; + }; + + TexturePool(renderengine::RenderEngine& renderEngine) : mRenderEngine(renderEngine) {} + + virtual ~TexturePool() = default; + + // Sets the display size for the texture pool. + // This will trigger a reallocation for all remaining textures in the pool. + // setDisplaySize must be called for the texture pool to be used. + void setDisplaySize(ui::Size size); + + // Borrows a new texture from the pool. + // If the pool is currently starved of textures, then a new texture is generated. + // When the AutoTexture object is destroyed, the scratch texture is automatically returned + // to the pool. + std::shared_ptr<AutoTexture> borrowTexture(); + +protected: + // Proteted visibility so that they can be used for testing + const static constexpr size_t kMinPoolSize = 3; + const static constexpr size_t kMaxPoolSize = 4; + + struct Entry { + std::shared_ptr<renderengine::ExternalTexture> texture; + sp<Fence> fence; + }; + + std::deque<Entry> mPool; + +private: + std::shared_ptr<renderengine::ExternalTexture> genTexture(); + // Returns a previously borrowed texture to the pool. + void returnTexture(std::shared_ptr<renderengine::ExternalTexture>&& texture, + const sp<Fence>& fence); + renderengine::RenderEngine& mRenderEngine; + ui::Size mSize; +}; + +} // namespace android::compositionengine::impl::planner |