Bug 1242448 - Ensure the tile pool does not hold textures during shutdown. r=edwin

gfx/2d/Logging.h

@@ -135,6 +135,7 @@ enum class LogReason : int {
   PAllocTextureBackendMismatch,
   GetFontFileDataFailed,
   MessageChannelCloseFailure,
+  TextureAliveAfterShutdown,
   // End
   MustBeLessThanThis = 101,
 };

gfx/layers/client/ClientLayerManager.cpp

@@ -108,6 +108,7 @@ ClientLayerManager::ClientLayerManager(nsIWidget* aWidget)
   mMemoryPressureObserver = new MemoryPressureObserver(this);
 }
 
+
 ClientLayerManager::~ClientLayerManager()
 {
   if (mTransactionIdAllocator) {
@@ -128,6 +129,18 @@ ClientLayerManager::~ClientLayerManager()
   MOZ_COUNT_DTOR(ClientLayerManager);
 }
 
+void
+ClientLayerManager::Destroy()
+{
+  // It's important to call ClearCachedResource before Destroy because the
+  // former will early-return if the later has already run.
+  ClearCachedResources();
+  for (size_t i = 0; i < mTexturePools.Length(); i++) {
+    mTexturePools[i]->Destroy();
+  }
+  LayerManager::Destroy();
+}
+
 int32_t
 ClientLayerManager::GetMaxTextureSize() const
 {
@@ -707,6 +720,8 @@ ClientLayerManager::SetIsFirstPaint()
 TextureClientPool*
 ClientLayerManager::GetTexturePool(SurfaceFormat aFormat, TextureFlags aFlags)
 {
+  MOZ_DIAGNOSTIC_ASSERT(!mDestroyed);
+
   for (size_t i = 0; i < mTexturePools.Length(); i++) {
     if (mTexturePools[i]->GetFormat() == aFormat &&
         mTexturePools[i]->GetFlags() == aFlags) {

gfx/layers/client/ClientLayerManager.h

@@ -44,13 +44,7 @@ class ClientLayerManager final : public LayerManager
 public:
   explicit ClientLayerManager(nsIWidget* aWidget);
 
-  virtual void Destroy() override
-  {
-    // It's important to call ClearCachedResource before Destroy because the
-    // former will early-return if the later has already run.
-    ClearCachedResources();
-    LayerManager::Destroy();
-  }
+  virtual void Destroy() override;
 
 protected:
   virtual ~ClientLayerManager();

gfx/layers/client/TextureClientPool.cpp

@@ -194,9 +194,9 @@ TextureClientPool::ShrinkToMaximumSize()
     } else {
       if (!mTextureClients.size()) {
         // Getting here means we're over our desired number of TextureClients
-        // with none in the pool. This can happen for pathological cases, or
-        // it could mean that mMaxTextureClients needs adjusting for whatever
-        // device we're running on.
+        // with none in the pool. This can happen during shutdown, or for
+        // pathological cases, or it could mean that mMaxTextureClients needs
+        // adjusting for whatever device we're running on.
         TCP_LOG("TexturePool %p encountering pathological case!\n", this);
         break;
       }
@@ -269,5 +269,11 @@ TextureClientPool::Clear()
   }
 }
 
+void TextureClientPool::Destroy()
+{
+  Clear();
+  mMaxTextureClients = 0;
+}
+
 } // namespace layers
 } // namespace mozilla

gfx/layers/client/TextureClientPool.h

@@ -105,6 +105,11 @@ public:
   gfx::SurfaceFormat GetFormat() { return mFormat; }
   TextureFlags GetFlags() const { return mFlags; }
 
+  /**
+   * Clear the pool and put it in a state where it won't recycle any new texture.
+   */
+  void Destroy();
+
 private:
   // The minimum size of the pool (the number of tiles that will be kept after
   // shrinking).

gfx/layers/ipc/LayerTransactionChild.cpp

@@ -6,6 +6,7 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "LayerTransactionChild.h"
+#include "mozilla/gfx/Logging.h"
 #include "mozilla/layers/CompositableClient.h"  // for CompositableChild
 #include "mozilla/layers/PCompositableChild.h"  // for PCompositableChild
 #include "mozilla/layers/PLayerChild.h"  // for PLayerChild
@@ -39,7 +40,11 @@ LayerTransactionChild::Destroy()
   const ManagedContainer<PTextureChild>& textures = ManagedPTextureChild();
   for (auto iter = textures.ConstIter(); !iter.Done(); iter.Next()) {
     TextureClient* texture = TextureClient::AsTextureClient(iter.Get()->GetKey());
+
     if (texture) {
+      // TODO: cf bug 1242448.
+      //gfxDevCrash(gfx::LogReason::TextureAliveAfterShutdown)
+      //  << "A texture is held alive after shutdown (PCompositorBridge)";
       texture->Destroy();
     }
   }

gfx/layers/ipc/LayerTransactionParent.cpp

@@ -179,6 +179,8 @@ LayerTransactionParent::Destroy()
   }
   InfallibleTArray<PTextureParent*> textures;
   ManagedPTextureParent(textures);
+  // We expect all textures to be destroyed by now.
+  MOZ_DIAGNOSTIC_ASSERT(textures.Length() == 0);
   for (unsigned int i = 0; i < textures.Length(); ++i) {
     RefPtr<TextureHost> tex = TextureHost::AsTextureHost(textures[i]);
     tex->DeallocateDeviceData();