Skip client composition requests

Keep track of client compositions requests in CompositionEngine and
the buffer used to render the request. If the requests do not change
and the buffer matches, reuse the buffer instead of going
to client composition.

Certain layers properties (buffer format, rounded corner or shadows)
will force the device to go into GPU or mixed composition. In mixed
composition scenarios, we can avoid redundant client composition
requests by reusing the RenderSurface buffers. If the device goes
into GPU composition then all the layers will be composited and there
will be no performance benefit.

Bug: b/136561771, b/144690120

Test: dump SurfaceFlinger --timestats -dump
Test: manual testing with mixed and gpu composition scenarios
Test: atest libcompositionengine_test libsurfaceflinger_unittest SurfaceFlinger_test
Change-Id: I466d5dcded0c9fcfa64bc72fd91dfaddd795f315
diff --git a/libs/renderengine/gl/GLESRenderEngine.cpp b/libs/renderengine/gl/GLESRenderEngine.cpp
index 09659fe..e257704 100644
--- a/libs/renderengine/gl/GLESRenderEngine.cpp
+++ b/libs/renderengine/gl/GLESRenderEngine.cpp
@@ -960,7 +960,7 @@
 }
 
 status_t GLESRenderEngine::drawLayers(const DisplaySettings& display,
-                                      const std::vector<LayerSettings>& layers,
+                                      const std::vector<const LayerSettings*>& layers,
                                       ANativeWindowBuffer* const buffer,
                                       const bool useFramebufferCache, base::unique_fd&& bufferFence,
                                       base::unique_fd* drawFence) {
@@ -985,9 +985,9 @@
     // Blurs in multiple layers are not supported, given the cost of the shader.
     const LayerSettings* blurLayer = nullptr;
     if (CC_LIKELY(mBlurFilter != nullptr)) {
-        for (auto const& layer : layers) {
-            if (layer.backgroundBlurRadius > 0) {
-                blurLayer = &layer;
+        for (auto const layer : layers) {
+            if (layer->backgroundBlurRadius > 0) {
+                blurLayer = layer;
             }
         }
     }
@@ -1035,9 +1035,9 @@
                         .setTexCoords(2 /* size */)
                         .setCropCoords(2 /* size */)
                         .build();
-    for (auto const& layer : layers) {
-        if (blurLayer == &layer) {
-            auto status = mBlurFilter->prepare(layer.backgroundBlurRadius);
+    for (auto const layer : layers) {
+        if (blurLayer == layer) {
+            auto status = mBlurFilter->prepare(layer->backgroundBlurRadius);
             if (status != NO_ERROR) {
                 ALOGE("Failed to render blur effect! Aborting GPU composition for buffer (%p).",
                       buffer->handle);
@@ -1065,40 +1065,40 @@
             }
         }
 
-        mState.maxMasteringLuminance = layer.source.buffer.maxMasteringLuminance;
-        mState.maxContentLuminance = layer.source.buffer.maxContentLuminance;
-        mState.projectionMatrix = projectionMatrix * layer.geometry.positionTransform;
+        mState.maxMasteringLuminance = layer->source.buffer.maxMasteringLuminance;
+        mState.maxContentLuminance = layer->source.buffer.maxContentLuminance;
+        mState.projectionMatrix = projectionMatrix * layer->geometry.positionTransform;
 
-        const FloatRect bounds = layer.geometry.boundaries;
+        const FloatRect bounds = layer->geometry.boundaries;
         Mesh::VertexArray<vec2> position(mesh.getPositionArray<vec2>());
         position[0] = vec2(bounds.left, bounds.top);
         position[1] = vec2(bounds.left, bounds.bottom);
         position[2] = vec2(bounds.right, bounds.bottom);
         position[3] = vec2(bounds.right, bounds.top);
 
-        setupLayerCropping(layer, mesh);
-        setColorTransform(display.colorTransform * layer.colorTransform);
+        setupLayerCropping(*layer, mesh);
+        setColorTransform(display.colorTransform * layer->colorTransform);
 
         bool usePremultipliedAlpha = true;
         bool disableTexture = true;
         bool isOpaque = false;
-        if (layer.source.buffer.buffer != nullptr) {
+        if (layer->source.buffer.buffer != nullptr) {
             disableTexture = false;
-            isOpaque = layer.source.buffer.isOpaque;
+            isOpaque = layer->source.buffer.isOpaque;
 
-            sp<GraphicBuffer> gBuf = layer.source.buffer.buffer;
-            bindExternalTextureBuffer(layer.source.buffer.textureName, gBuf,
-                                      layer.source.buffer.fence);
+            sp<GraphicBuffer> gBuf = layer->source.buffer.buffer;
+            bindExternalTextureBuffer(layer->source.buffer.textureName, gBuf,
+                                      layer->source.buffer.fence);
 
-            usePremultipliedAlpha = layer.source.buffer.usePremultipliedAlpha;
-            Texture texture(Texture::TEXTURE_EXTERNAL, layer.source.buffer.textureName);
-            mat4 texMatrix = layer.source.buffer.textureTransform;
+            usePremultipliedAlpha = layer->source.buffer.usePremultipliedAlpha;
+            Texture texture(Texture::TEXTURE_EXTERNAL, layer->source.buffer.textureName);
+            mat4 texMatrix = layer->source.buffer.textureTransform;
 
             texture.setMatrix(texMatrix.asArray());
-            texture.setFiltering(layer.source.buffer.useTextureFiltering);
+            texture.setFiltering(layer->source.buffer.useTextureFiltering);
 
             texture.setDimensions(gBuf->getWidth(), gBuf->getHeight());
-            setSourceY410BT2020(layer.source.buffer.isY410BT2020);
+            setSourceY410BT2020(layer->source.buffer.isY410BT2020);
 
             renderengine::Mesh::VertexArray<vec2> texCoords(mesh.getTexCoordArray<vec2>());
             texCoords[0] = vec2(0.0, 0.0);
@@ -1108,32 +1108,32 @@
             setupLayerTexturing(texture);
         }
 
-        const half3 solidColor = layer.source.solidColor;
-        const half4 color = half4(solidColor.r, solidColor.g, solidColor.b, layer.alpha);
+        const half3 solidColor = layer->source.solidColor;
+        const half4 color = half4(solidColor.r, solidColor.g, solidColor.b, layer->alpha);
         // Buffer sources will have a black solid color ignored in the shader,
         // so in that scenario the solid color passed here is arbitrary.
         setupLayerBlending(usePremultipliedAlpha, isOpaque, disableTexture, color,
-                           layer.geometry.roundedCornersRadius);
-        if (layer.disableBlending) {
+                           layer->geometry.roundedCornersRadius);
+        if (layer->disableBlending) {
             glDisable(GL_BLEND);
         }
-        setSourceDataSpace(layer.sourceDataspace);
+        setSourceDataSpace(layer->sourceDataspace);
 
-        if (layer.shadow.length > 0.0f) {
-            handleShadow(layer.geometry.boundaries, layer.geometry.roundedCornersRadius,
-                         layer.shadow);
+        if (layer->shadow.length > 0.0f) {
+            handleShadow(layer->geometry.boundaries, layer->geometry.roundedCornersRadius,
+                         layer->shadow);
         }
         // We only want to do a special handling for rounded corners when having rounded corners
         // is the only reason it needs to turn on blending, otherwise, we handle it like the
         // usual way since it needs to turn on blending anyway.
-        else if (layer.geometry.roundedCornersRadius > 0.0 && color.a >= 1.0f && isOpaque) {
-            handleRoundedCorners(display, layer, mesh);
+        else if (layer->geometry.roundedCornersRadius > 0.0 && color.a >= 1.0f && isOpaque) {
+            handleRoundedCorners(display, *layer, mesh);
         } else {
             drawMesh(mesh);
         }
 
         // Cleanup if there's a buffer source
-        if (layer.source.buffer.buffer != nullptr) {
+        if (layer->source.buffer.buffer != nullptr) {
             disableBlending();
             setSourceY410BT2020(false);
             disableTexturing();