Bug 570620, part i: Implement ShadowLayer::Disconnect() for common-case shutdown, and ShadowableLayer::Disconnect() for emergency-case shutdown. r=vlad

gfx/layers/Makefile.in

@@ -105,10 +105,14 @@ ifdef MOZ_IPC #{
 EXPORTS_NAMESPACES = mozilla/layers
 EXPORTS_mozilla/layers =\
         ShadowLayers.h \
+        ShadowLayersChild.h \
+        ShadowLayersParent.h \
         $(NULL)
 
 CPPSRCS += \
         ShadowLayers.cpp \
+        ShadowLayerChild.cpp \
+        ShadowLayersChild.cpp \
         ShadowLayerParent.cpp \
         ShadowLayersParent.cpp \
         $(NULL)
@@ -135,4 +139,3 @@ LayerManagerOGLShaders.h: LayerManagerOGLShaders.txt genshaders.py $(GLOBAL_DEPS
 LayerManagerOGL.$(OBJ_SUFFIX): LayerManagerOGLShaders.h
 
 GARBAGE += LayerManagerOGLShaders.h
-

gfx/layers/basic/BasicLayers.cpp

@@ -1177,6 +1177,16 @@ public:
   {
     NS_RUNTIMEABORT("if this default impl is called, |aBuffer| leaks");
   }
+
+  virtual void Disconnect()
+  {
+    // This is an "emergency Disconnect()", called when the compositing
+    // process has died.  |mShadow| and our Shmem buffers are
+    // automatically managed by IPDL, so we don't need to explicitly
+    // free them here (it's hard to get that right on emergency
+    // shutdown anyway).
+    mShadow = nsnull;
+  }
 };
 
 static ShadowableLayer*
@@ -1212,6 +1222,11 @@ public:
   virtual Layer* AsLayer() { return this; }
   virtual ShadowableLayer* AsShadowableLayer() { return this; }
 
+  virtual void Disconnect()
+  {
+    BasicShadowableLayer::Disconnect();
+  }
+
 private:
   BasicShadowLayerManager* ShadowManager()
   {
@@ -1271,6 +1286,12 @@ public:
     mBackBuffer = aBuffer;
   }
 
+  virtual void Disconnect()
+  {
+    mBackBuffer = nsnull;
+    BasicShadowableLayer::Disconnect();
+  }
+
 private:
   BasicShadowLayerManager* BasicManager()
   {
@@ -1375,6 +1396,12 @@ public:
     mBackSurface = aBuffer;
   }
 
+  virtual void Disconnect()
+  {
+    mBackSurface = nsnull;
+    BasicShadowableLayer::Disconnect();
+  }
+
 private:
   BasicShadowLayerManager* BasicManager()
   {
@@ -1439,6 +1466,11 @@ public:
 
   virtual Layer* AsLayer() { return this; }
   virtual ShadowableLayer* AsShadowableLayer() { return this; }
+
+  virtual void Disconnect()
+  {
+    BasicShadowableLayer::Disconnect();
+  }
 };
 
 class BasicShadowableCanvasLayer : public BasicCanvasLayer,
@@ -1476,6 +1508,12 @@ public:
   {
     mBackBuffer = aBuffer;
   }
+ 
+  virtual void Disconnect()
+  {
+    mBackBuffer = nsnull;
+    BasicShadowableLayer::Disconnect();
+  }
 
 private:
   BasicShadowLayerManager* BasicManager()
@@ -1567,7 +1605,15 @@ public:
   {
     MOZ_COUNT_CTOR(BasicShadowThebesLayer);
   }
-  virtual ~BasicShadowThebesLayer();
+  virtual ~BasicShadowThebesLayer()
+  {
+    // If Disconnect() wasn't called on us, then we assume that the
+    // remote side shut down and IPC is disconnected, so we let IPDL
+    // clean up our front surface Shmem.
+    MOZ_COUNT_DTOR(BasicShadowThebesLayer);
+  }
+
+  virtual void Disconnect();
 
   virtual already_AddRefed<gfxSharedImageSurface>
   Swap(gfxSharedImageSurface* aNewFront,
@@ -1591,7 +1637,8 @@ private:
   ShadowThebesLayerBuffer mFrontBuffer;
 };
 
-BasicShadowThebesLayer::~BasicShadowThebesLayer()
+void
+BasicShadowThebesLayer::Disconnect()
 {
   nsRefPtr<gfxSharedImageSurface> frontBuffer =
     mFrontBuffer.Swap(0, nsIntRect());
@@ -1599,7 +1646,7 @@ BasicShadowThebesLayer::~BasicShadowThebesLayer()
     BasicManager()->ShadowLayerManager::DestroySharedSurface(frontBuffer);
   }
 
-  MOZ_COUNT_DTOR(BasicShadowThebesLayer);
+  ShadowThebesLayer::Disconnect();
 }
 
 void
@@ -1613,6 +1660,10 @@ BasicShadowThebesLayer::Paint(gfxContext* aContext,
   NS_ASSERTION(BasicManager()->IsRetained(),
                "ShadowThebesLayer makes no sense without retained mode");
 
+  if (!mFrontBuffer.GetBuffer()) {
+    return;
+  }
+
   gfxContext* target = BasicManager()->GetTarget();
   NS_ASSERTION(target, "We shouldn't be called if there's no target");
 
@@ -1635,12 +1686,11 @@ public:
   }
   virtual ~BasicShadowImageLayer()
   {
-    if (mFrontSurface) {
-      BasicManager()->ShadowLayerManager::DestroySharedSurface(mFrontSurface);
-    }
     MOZ_COUNT_DTOR(BasicShadowImageLayer);
   }
 
+  virtual void Disconnect();
+
   virtual PRBool Init(gfxSharedImageSurface* front, const nsIntSize& size);
 
   virtual already_AddRefed<gfxSharedImageSurface>
@@ -1662,6 +1712,17 @@ protected:
   gfxIntSize mSize;
 };
 
+void
+BasicShadowImageLayer::Disconnect()
+{
+  if (mFrontSurface) {
+    BasicManager()->ShadowLayerManager::DestroySharedSurface(mFrontSurface);
+  }
+  mFrontSurface = nsnull;
+
+  ShadowImageLayer::Disconnect();
+}
+
 PRBool
 BasicShadowImageLayer::Init(gfxSharedImageSurface* front,
                             const nsIntSize& size)
@@ -1685,6 +1746,10 @@ BasicShadowImageLayer::Paint(gfxContext* aContext,
                              void* aCallbackData,
                              float aOpacity)
 {
+  if (!mFrontSurface) {
+    return;
+  }
+
   nsRefPtr<gfxPattern> pat = new gfxPattern(mFrontSurface);
   pat->SetFilter(mFilter);
   BasicImageLayer::PaintContext(pat, mSize, aOpacity, aContext);
@@ -1701,12 +1766,11 @@ public:
   }
   virtual ~BasicShadowCanvasLayer()
   {
-    if (mFrontSurface) {
-      BasicManager()->ShadowLayerManager::DestroySharedSurface(mFrontSurface);
-    }
     MOZ_COUNT_DTOR(BasicShadowCanvasLayer);
   }
 
+  virtual void Disconnect();
+
   virtual void Initialize(const Data& aData);
 
   virtual void Updated(const nsIntRect& aRect)
@@ -1730,6 +1794,17 @@ private:
   nsIntRect mBounds;
 };
 
+void
+BasicShadowCanvasLayer::Disconnect()
+{
+  if (mFrontSurface) {
+    BasicManager()->ShadowLayerManager::DestroySharedSurface(mFrontSurface);
+  }
+  mFrontSurface = nsnull;
+
+  ShadowCanvasLayer::Disconnect();
+}
+
 void
 BasicShadowCanvasLayer::Initialize(const Data& aData)
 {
@@ -1755,11 +1830,13 @@ BasicShadowCanvasLayer::Paint(gfxContext* aContext,
                               void* aCallbackData,
                               float aOpacity)
 {
-  MOZ_LAYERS_LOG(("[ShadowLayersChild] %s()", __FUNCTION__));
-
   NS_ASSERTION(BasicManager()->InDrawing(),
                "Can only draw in drawing phase");
 
+  if (!mFrontSurface) {
+    return;
+  }
+
   nsRefPtr<gfxPattern> pat = new gfxPattern(mFrontSurface);
 
   pat->SetFilter(mFilter);

gfx/layers/ipc/ShadowLayerChild.cpp

@@ -0,0 +1,71 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=8 et :
+ */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (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.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla Code.
+ *
+ * The Initial Developer of the Original Code is
+ *   The Mozilla Foundation
+ * Portions created by the Initial Developer are Copyright (C) 2010
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Chris Jones <jones.chris.g@gmail.com>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include "ShadowLayerChild.h"
+#include "Layers.h"
+#include "ShadowLayers.h"
+
+namespace mozilla {
+namespace layers {
+
+ShadowLayerChild::ShadowLayerChild(ShadowableLayer* aLayer)
+  : mLayer(aLayer)
+{ }
+
+ShadowLayerChild::~ShadowLayerChild()
+{ }
+
+void
+ShadowLayerChild::ActorDestroy(ActorDestroyReason why)
+{
+  NS_ABORT_IF_FALSE(AncestorDeletion != why,
+                    "shadowable layer should have been cleaned up by now");
+
+  if (AbnormalShutdown == why) {
+    // This is last-ditch emergency shutdown.  Just have the layer
+    // forget its IPDL resources; IPDL-generated code will clean up
+    // automatically in this case.
+    mLayer->AsLayer()->Disconnect();
+    mLayer = nsnull;
+  }
+}
+
+}  // namespace layers
+}  // namespace mozilla

gfx/layers/ipc/ShadowLayerChild.h

@@ -51,14 +51,15 @@ class ShadowableLayer;
 class ShadowLayerChild : public PLayerChild
 {
 public:
-  ShadowLayerChild(ShadowableLayer* aLayer) : mLayer(aLayer)
-  { }
-
-  virtual ~ShadowLayerChild()
-  { }
+  ShadowLayerChild(ShadowableLayer* aLayer);
+  virtual ~ShadowLayerChild();
 
   ShadowableLayer* layer() const { return mLayer; }
 
+protected:
+  NS_OVERRIDE
+  virtual void ActorDestroy(ActorDestroyReason why);
+
 private:
   ShadowableLayer* mLayer;
 };

gfx/layers/ipc/ShadowLayerParent.cpp

@@ -67,11 +67,26 @@ ShadowLayerParent::AsContainer() const
   return static_cast<ContainerLayer*>(AsLayer());
 }
 
-bool
-ShadowLayerParent::Recv__delete__()
+void
+ShadowLayerParent::ActorDestroy(ActorDestroyReason why)
 {
+  switch (why) {
+  case AncestorDeletion:
+    NS_RUNTIMEABORT("shadow layer deleted out of order!");
+    return;                     // unreached
+
+  case Deletion:
+    mLayer->Disconnect();
+    break;
+
+  case AbnormalShutdown:
+  case NormalShutdown:
+    // let IPDL-generated code automatically clean up Shmems and so
+    // forth; our channel is disconnected anyway
+    break;
+  }
+
   mLayer = NULL;
-  return true;
 }
 
 } // namespace layers

gfx/layers/ipc/ShadowLayerParent.h

@@ -64,7 +64,8 @@ public:
   ContainerLayer* AsContainer() const;
 
 private:
-  NS_OVERRIDE virtual bool Recv__delete__();
+  NS_OVERRIDE
+  virtual void ActorDestroy(ActorDestroyReason why);
 
   nsRefPtr<Layer> mLayer;
 };

gfx/layers/ipc/ShadowLayersChild.cpp

@@ -0,0 +1,75 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=8 et :
+ */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (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.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla Code.
+ *
+ * The Initial Developer of the Original Code is
+ *   The Mozilla Foundation
+ * Portions created by the Initial Developer are Copyright (C) 2010
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *   Chris Jones <jones.chris.g@gmail.com>
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#include "ShadowLayerChild.h"
+#include "ShadowLayersChild.h"
+
+namespace mozilla {
+namespace layers {
+
+void
+ShadowLayersChild::Destroy()
+{
+  NS_ABORT_IF_FALSE(0 == ManagedPLayerChild().Length(),
+                    "layers should have been cleaned up by now");
+  //
+  // FIXME: uncomment this when we have a manager
+  //
+  //PLayersChild::Send__delete__(this);
+  // WARNING: |this| has gone to the great heap in the sky
+}
+
+PLayerChild*
+ShadowLayersChild::AllocPLayer()
+{
+  // we always use the "power-user" ctor
+  NS_RUNTIMEABORT("not reached");
+  return NULL;
+}
+
+bool
+ShadowLayersChild::DeallocPLayer(PLayerChild* actor)
+{
+  delete actor;
+  return true;
+}
+
+}  // namespace layers
+}  // namespace mozilla

gfx/layers/ipc/ShadowLayersChild.h

@@ -42,7 +42,6 @@
 #define mozilla_layers_ShadowLayersChild_h
 
 #include "mozilla/layers/PLayersChild.h"
-#include "mozilla/layers/ShadowLayerChild.h"
 
 namespace mozilla {
 namespace layers {
@@ -53,17 +52,18 @@ public:
   ShadowLayersChild() { }
   ~ShadowLayersChild() { }
 
-protected:
-  NS_OVERRIDE virtual PLayerChild* AllocPLayer() {
-    // we always use the "power-user" ctor
-    NS_RUNTIMEABORT("not reached");
-    return NULL;
-  }
+  /**
+   * Clean this up, finishing with Send__delete__().
+   *
+   * It is expected (checked with an assert) that all shadow layers
+   * created by this have already been destroyed and
+   * Send__delete__()d by the time this method is called.
+   */
+  void Destroy();
 
-  NS_OVERRIDE virtual bool DeallocPLayer(PLayerChild* actor) {
-    delete actor;
-    return true;
-  }
+protected:
+  NS_OVERRIDE virtual PLayerChild* AllocPLayer();
+  NS_OVERRIDE virtual bool DeallocPLayer(PLayerChild* actor);
 };
 
 } // namespace layers