WebGL: Don't destroy mailbox textures in the destructor until they're released.

Source/platform/graphics/gpu/DrawingBuffer.cpp

 /*
  * Copyright (c) 2010, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 59 matching lines @@
         m_context->bindTexture(GL_TEXTURE_2D, m_oldTextureUnitZeroId);
         m_context->activeTexture(m_oldActiveTextureUnit);
     }
 
 private:
     blink::WebGraphicsContext3D* m_context;
     GLenum m_oldActiveTextureUnit;
     Platform3DObject m_oldTextureUnitZeroId;
 };
 
-PassRefPtr<DrawingBuffer> DrawingBuffer::create(blink::WebGraphicsContext3D* context, const IntSize& size, PreserveDrawingBuffer preserve, PassRefPtr<ContextEvictionManager> contextEvictionManager)
+PassRefPtr<DrawingBuffer> DrawingBuffer::create(PassOwnPtr<blink::WebGraphicsContext3D> context, const IntSize& size, PreserveDrawingBuffer preserve, PassRefPtr<ContextEvictionManager> contextEvictionManager)
 {
-    ASSERT(context);
-    Extensions3DUtil extensionsUtil(context);
+    Extensions3DUtil extensionsUtil(context.get());
     bool multisampleSupported = extensionsUtil.supportsExtension("GL_CHROMIUM_framebuffer_multisample")
         && extensionsUtil.supportsExtension("GL_OES_rgb8_rgba8");
     if (multisampleSupported) {
         extensionsUtil.ensureExtensionEnabled("GL_CHROMIUM_framebuffer_multisample");
         extensionsUtil.ensureExtensionEnabled("GL_OES_rgb8_rgba8");
     }
     bool packedDepthStencilSupported = extensionsUtil.supportsExtension("GL_OES_packed_depth_stencil");
     if (packedDepthStencilSupported)
         extensionsUtil.ensureExtensionEnabled("GL_OES_packed_depth_stencil");
 
     RefPtr<DrawingBuffer> drawingBuffer = adoptRef(new DrawingBuffer(context, multisampleSupported, packedDepthStencilSupported, preserve, contextEvictionManager));
     if (!drawingBuffer->initialize(size))
         return PassRefPtr<DrawingBuffer>();
     return drawingBuffer.release();
 }
 
-DrawingBuffer::DrawingBuffer(blink::WebGraphicsContext3D* context,
+DrawingBuffer::DrawingBuffer(PassOwnPtr<blink::WebGraphicsContext3D> context,
     bool multisampleExtensionSupported,
     bool packedDepthStencilExtensionSupported,
     PreserveDrawingBuffer preserve,
     PassRefPtr<ContextEvictionManager> contextEvictionManager)
     : m_preserveDrawingBuffer(preserve)
     , m_scissorEnabled(false)
     , m_texture2DBinding(0)
     , m_framebufferBinding(0)
     , m_activeTextureUnit(GL_TEXTURE0)
     , m_context(context)
@@ skipping 18 matching lines @@
     , m_sampleCount(4)
     , m_packAlignment(4)
     , m_contextEvictionManager(contextEvictionManager)
 {
     // Used by browser tests to detect the use of a DrawingBuffer.
     TRACE_EVENT_INSTANT0("test_gpu", "DrawingBufferCreation");
 }
 
 DrawingBuffer::~DrawingBuffer()
 {
-    releaseResources();
+    ASSERT(!m_context);
 }
 
 void DrawingBuffer::markContentsChanged()
 {
     m_contentsChanged = true;
     m_contentsChangeCommitted = false;
     m_layerComposited = false;
 }
 
 bool DrawingBuffer::layerComposited() const
 {
     return m_layerComposited;
 }
 
 void DrawingBuffer::markLayerComposited()
 {
     m_layerComposited = true;
 }
 
 blink::WebGraphicsContext3D* DrawingBuffer::context()
 {
-    return m_context;
+    return m_context.get();
 }
 
 bool DrawingBuffer::prepareMailbox(blink::WebExternalTextureMailbox* outMailbox, blink::WebExternalBitmap* bitmap)
 {
     if (!m_contentsChanged)
         return false;
 
     m_context->makeContextCurrent();
 
     // Resolve the multisampled buffer into m_colorBuffer texture.
     if (multisample())
         commit();
 
     if (bitmap) {
         bitmap->setSize(size());
 
         unsigned char* pixels = bitmap->pixels();
         bool needPremultiply = m_attributes.alpha && !m_attributes.premultipliedAlpha;
         WebGLImageConversion::AlphaOp op = needPremultiply ? WebGLImageConversion::AlphaDoPremultiply : WebGLImageConversion::AlphaDoNothing;
         if (pixels)
             readBackFramebuffer(pixels, size().width(), size().height(), ReadbackSkia, op);
     }
 
     // We must restore the texture binding since creating new textures,
     // consuming and producing mailboxes changes it.
-    ScopedTextureUnit0BindingRestorer restorer(m_context, m_activeTextureUnit, m_texture2DBinding);
+    ScopedTextureUnit0BindingRestorer restorer(m_context.get(), m_activeTextureUnit, m_texture2DBinding);
 
     // First try to recycle an old buffer.
     RefPtr<MailboxInfo> frontColorBufferMailbox = recycledMailbox();
 
     // No buffer available to recycle, create a new one.
     if (!frontColorBufferMailbox) {
         unsigned newColorBuffer = createColorTexture(m_size);
         // Bad things happened, abandon ship.
         if (!newColorBuffer)
             return false;
@@ skipping 26 matching lines @@
     frontColorBufferMailbox->mailbox.syncPoint = m_context->insertSyncPoint();
     markLayerComposited();
 
     *outMailbox = frontColorBufferMailbox->mailbox;
     m_frontColorBuffer = frontColorBufferMailbox->textureId;
     return true;
 }
 
 void DrawingBuffer::mailboxReleased(const blink::WebExternalTextureMailbox& mailbox)
 {
+    if (m_selfToWaitForMailboxes) {
+        releaseSelf(mailbox);

[Justin Novosad, 2014/02/18 18:07:33]

naming nit: releaseSelfIfNeeded or releaseSelfIfFinalMailboxReleased

+        return;
+    }
+
     for (size_t i = 0; i < m_textureMailboxes.size(); i++) {
         RefPtr<MailboxInfo> mailboxInfo = m_textureMailboxes[i];
         if (!memcmp(mailboxInfo->mailbox.name, mailbox.name, sizeof(mailbox.name))) {
             mailboxInfo->mailbox.syncPoint = mailbox.syncPoint;
             m_recycledMailboxes.prepend(mailboxInfo.release());
             return;
         }
     }
     ASSERT_NOT_REACHED();
 }
 
+
+void DrawingBuffer::releaseSelf(const blink::WebExternalTextureMailbox& mailbox)
+{
+    ASSERT(!m_textureMailboxes.isEmpty());
+    for (size_t i = 0; i < m_textureMailboxes.size(); i++) {
+        RefPtr<MailboxInfo> mailboxInfo = m_textureMailboxes[i];
+        if (!memcmp(mailboxInfo->mailbox.name, mailbox.name, sizeof(mailboxInfo->mailbox.name))) {
+            m_context->makeContextCurrent();
+            m_context->deleteTexture(mailboxInfo->textureId);
+            m_textureMailboxes.remove(i);
+            break;
+        }
+    }
+    if (!m_textureMailboxes.isEmpty())
+        return;
+
+    m_context.clear();
+    m_layer.clear();
+    m_selfToWaitForMailboxes.clear();
+}
+
 PassRefPtr<DrawingBuffer::MailboxInfo> DrawingBuffer::recycledMailbox()
 {
     if (m_recycledMailboxes.isEmpty())
         return PassRefPtr<MailboxInfo>();
 
     RefPtr<MailboxInfo> mailboxInfo = m_recycledMailboxes.last().release();
     m_recycledMailboxes.removeLast();
 
     if (mailboxInfo->mailbox.syncPoint) {
         m_context->waitSyncPoint(mailboxInfo->mailbox.syncPoint);
@@ skipping 154 matching lines @@
 
     m_context->flush();
 }
 
 void DrawingBuffer::releaseResources()
 {
     m_context->makeContextCurrent();
 
     clearPlatformLayer();
 
-    for (size_t i = 0; i < m_textureMailboxes.size(); i++)
-        m_context->deleteTexture(m_textureMailboxes[i]->textureId);
+    for (size_t i = 0; i < m_recycledMailboxes.size(); i++) {
+        m_context->deleteTexture(m_recycledMailboxes[i]->textureId);
+
+        for (size_t j = 0; j < m_textureMailboxes.size(); j++) {
+            RefPtr<MailboxInfo> mailboxInfo = m_textureMailboxes[j];
+            if (mailboxInfo->textureId == m_recycledMailboxes[i]->textureId) {
+                ASSERT(!memcmp(mailboxInfo->mailbox.name, m_recycledMailboxes[i]->mailbox.name, sizeof(mailboxInfo->mailbox.name)));
+                m_textureMailboxes.remove(j);
+                break;
+            }
+        }
+    }
 
     if (m_multisampleColorBuffer)
         m_context->deleteRenderbuffer(m_multisampleColorBuffer);
 
     if (m_depthStencilBuffer)
         m_context->deleteRenderbuffer(m_depthStencilBuffer);
 
     if (m_depthBuffer)
         m_context->deleteRenderbuffer(m_depthBuffer);
 
     if (m_stencilBuffer)
         m_context->deleteRenderbuffer(m_stencilBuffer);
 
     if (m_multisampleFBO)
         m_context->deleteFramebuffer(m_multisampleFBO);
 
     if (m_fbo)
         m_context->deleteFramebuffer(m_fbo);
 
-    m_context = 0;
+    setSize(IntSize());
 
     m_colorBuffer = 0;
     m_frontColorBuffer = 0;
     m_multisampleColorBuffer = 0;
     m_depthStencilBuffer = 0;
     m_depthBuffer = 0;
     m_stencilBuffer = 0;
     m_multisampleFBO = 0;
     m_fbo = 0;
     m_contextEvictionManager.clear();
 
     m_recycledMailboxes.clear();
-    m_textureMailboxes.clear();
 
-    if (m_layer) {
+    if (m_layer)
         GraphicsLayer::unregisterContentsLayer(m_layer->layer());
+
+    if (m_textureMailboxes.isEmpty()) {
+        m_context.clear();
         m_layer.clear();
+        return;
     }
+    m_selfToWaitForMailboxes = this;
 }
 
 unsigned DrawingBuffer::createColorTexture(const IntSize& size)
 {
     unsigned offscreenColorTexture = m_context->createTexture();
     if (!offscreenColorTexture)
         return 0;
 
     m_context->bindTexture(GL_TEXTURE_2D, offscreenColorTexture);
     m_context->texParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
@@ skipping 384 matching lines @@
     }
 }
 
 void DrawingBuffer::texImage2DResourceSafe(GLenum target, GLint level, GLenum internalformat, GLsizei width, GLsizei height, GLint border, GLenum format, GLenum type, GLint unpackAlignment)
 {
     ASSERT(unpackAlignment == 1 || unpackAlignment == 2 || unpackAlignment == 4 || unpackAlignment == 8);
     m_context->texImage2D(target, level, internalformat, width, height, border, format, type, 0);
 }
 
 } // namespace WebCore