author Sotaro Ikeda <>
Tue, 02 Jun 2015 07:31:05 -0700
changeset 238636 b69b68b8a0a719261469c61e1f9c2f4c2c9e0cfe
parent 221069 6cf334e6acf80e8fe4ec56b550cec59bdd47bffd
permissions -rw-r--r--
Bug 1169200 - Send OpRemoveTextureAsync before actor destroyed. r=nical, a=jocheng

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at */


#include <stddef.h>                     // for size_t
#include <stdint.h>                     // for uint16_t
#include <algorithm>                    // for swap
#include <limits>
#include "Layers.h"                     // for LayerManager, etc
#include "TiledLayerBuffer.h"           // for TiledLayerBuffer
#include "Units.h"                      // for CSSPoint
#include "gfxTypes.h"
#include "mozilla/Attributes.h"         // for MOZ_OVERRIDE
#include "mozilla/RefPtr.h"             // for RefPtr
#include "mozilla/ipc/Shmem.h"          // for Shmem
#include "mozilla/ipc/SharedMemory.h"   // for SharedMemory
#include "mozilla/layers/AsyncCompositionManager.h"  // for ViewTransform
#include "mozilla/layers/CompositableClient.h"  // for CompositableClient
#include "mozilla/layers/CompositorTypes.h"  // for TextureInfo, etc
#include "mozilla/layers/LayersMessages.h" // for TileDescriptor
#include "mozilla/layers/TextureClient.h"
#include "mozilla/layers/TextureClientPool.h"
#include "ClientLayerManager.h"
#include "mozilla/mozalloc.h"           // for operator delete
#include "nsAutoPtr.h"                  // for nsRefPtr
#include "nsISupportsImpl.h"            // for MOZ_COUNT_DTOR
#include "nsPoint.h"                    // for nsIntPoint
#include "nsRect.h"                     // for nsIntRect
#include "nsRegion.h"                   // for nsIntRegion
#include "nsTArray.h"                   // for nsTArray, nsTArray_Impl, etc
#include "nsExpirationTracker.h"
#include "mozilla/layers/ISurfaceAllocator.h"
#include "gfxReusableSurfaceWrapper.h"
#include "pratom.h"                     // For PR_ATOMIC_INCREMENT/DECREMENT
#include "gfxPrefs.h"

namespace mozilla {
namespace layers {

class BasicTileDescriptor;
class ClientTiledPaintedLayer;
class ClientLayerManager;

// A class to help implement copy-on-write semantics for shared tiles.
class gfxSharedReadLock {
  virtual ~gfxSharedReadLock() {}


  virtual int32_t ReadLock() = 0;
  virtual int32_t ReadUnlock() = 0;
  virtual int32_t GetReadCount() = 0;
  virtual bool IsValid() const = 0;

  enum gfxSharedReadLockType {
  virtual gfxSharedReadLockType GetType() = 0;


class gfxMemorySharedReadLock : public gfxSharedReadLock {


  virtual int32_t ReadLock() MOZ_OVERRIDE;

  virtual int32_t ReadUnlock() MOZ_OVERRIDE;

  virtual int32_t GetReadCount() MOZ_OVERRIDE;

  virtual gfxSharedReadLockType GetType() MOZ_OVERRIDE { return TYPE_MEMORY; }

  virtual bool IsValid() const MOZ_OVERRIDE { return true; };

  int32_t mReadCount;

class gfxShmSharedReadLock : public gfxSharedReadLock {
  struct ShmReadLockInfo {
    int32_t readCount;

  explicit gfxShmSharedReadLock(ISurfaceAllocator* aAllocator);


  virtual int32_t ReadLock() MOZ_OVERRIDE;

  virtual int32_t ReadUnlock() MOZ_OVERRIDE;

  virtual int32_t GetReadCount() MOZ_OVERRIDE;

  virtual bool IsValid() const MOZ_OVERRIDE { return mAllocSuccess; };

  virtual gfxSharedReadLockType GetType() MOZ_OVERRIDE { return TYPE_SHMEM; }

  mozilla::layers::ShmemSection& GetShmemSection() { return mShmemSection; }

  static already_AddRefed<gfxShmSharedReadLock>
  Open(mozilla::layers::ISurfaceAllocator* aAllocator, const mozilla::layers::ShmemSection& aShmemSection)
    nsRefPtr<gfxShmSharedReadLock> readLock = new gfxShmSharedReadLock(aAllocator, aShmemSection);
    return readLock.forget();

  gfxShmSharedReadLock(ISurfaceAllocator* aAllocator, const mozilla::layers::ShmemSection& aShmemSection)
    : mAllocator(aAllocator)
    , mShmemSection(aShmemSection)
    , mAllocSuccess(true)

  ShmReadLockInfo* GetShmReadLockInfoPtr()
    return reinterpret_cast<ShmReadLockInfo*>
      (mShmemSection.shmem().get<char>() + mShmemSection.offset());

  RefPtr<ISurfaceAllocator> mAllocator;
  mozilla::layers::ShmemSection mShmemSection;
  bool mAllocSuccess;

 * Represent a single tile in tiled buffer. The buffer keeps tiles,
 * each tile keeps a reference to a texture client and a read-lock. This
 * read-lock is used to help implement a copy-on-write mechanism. The tile
 * should be locked before being sent to the compositor. The compositor should
 * unlock the read-lock as soon as it has finished with the buffer in the
 * TextureHost to prevent more textures being created than is necessary.
 * Ideal place to store per tile debug information.
struct TileClient
  // Placeholder

  TileClient(const TileClient& o);

  TileClient& operator=(const TileClient& o);

  bool operator== (const TileClient& o) const
    return mFrontBuffer == o.mFrontBuffer;

  bool operator!= (const TileClient& o) const
    return mFrontBuffer != o.mFrontBuffer;

  void SetLayerManager(ClientLayerManager *aManager)
    mManager = aManager;

  void SetCompositableClient(CompositableClient* aCompositableClient)
    mCompositableClient = aCompositableClient;

  bool IsPlaceholderTile()
    return mBackBuffer == nullptr && mFrontBuffer == nullptr;

  void ReadUnlock()
    MOZ_ASSERT(mFrontLock, "ReadLock with no gfxSharedReadLock");
    if (mFrontLock) {

  void ReadLock()
    MOZ_ASSERT(mFrontLock, "ReadLock with no gfxSharedReadLock");
    if (mFrontLock) {

  void Release()

  nsExpirationState *GetExpirationState() { return &mExpirationState; }

  TileDescriptor GetTileDescriptor();

  * Swaps the front and back buffers.
  void Flip();

  void DumpTexture(std::stringstream& aStream) {
    // TODO We should combine the OnWhite/OnBlack here an just output a single image.
    CompositableClient::DumpTextureClient(aStream, mFrontBuffer);

  * Returns an unlocked TextureClient that can be used for writing new
  * data to the tile. This may flip the front-buffer to the back-buffer if
  * the front-buffer is still locked by the host, or does not have an
  * internal buffer (and so will always be locked).
  * If getting the back buffer required copying pixels from the front buffer
  * then the copied region is stored in aAddPaintedRegion so the host side
  * knows to upload it.
  * If nullptr is returned, aTextureClientOnWhite is undefined.
  TextureClient* GetBackBuffer(const nsIntRegion& aDirtyRegion,
                               gfxContentType aContent, SurfaceMode aMode,
                               bool *aCreatedTextureClient,
                               nsIntRegion& aAddPaintedRegion,
                               RefPtr<TextureClient>* aTextureClientOnWhite);

  void DiscardFrontBuffer();

  void DiscardBackBuffer();

  /* We wrap the back buffer in a class that disallows assignment
   * so that we can track when ever it changes so that we can update
   * the expiry tracker for expiring the back buffers */
  class PrivateProtector {
      void Set(TileClient * container, RefPtr<TextureClient>);
      void Set(TileClient * container, TextureClient*);
      // Implicitly convert to TextureClient* because we can't chain
      // implicit conversion that would happen on RefPtr<TextureClient>
      operator TextureClient*() const { return mBuffer; }
      RefPtr<TextureClient> operator ->() { return mBuffer; }
      PrivateProtector& operator=(const PrivateProtector &);
      RefPtr<TextureClient> mBuffer;
  } mBackBuffer;
  RefPtr<TextureClient> mBackBufferOnWhite;
  RefPtr<TextureClient> mFrontBuffer;
  RefPtr<TextureClient> mFrontBufferOnWhite;
  RefPtr<gfxSharedReadLock> mBackLock;
  RefPtr<gfxSharedReadLock> mFrontLock;
  RefPtr<ClientLayerManager> mManager;
  CompositableClient* mCompositableClient;
  TimeStamp        mLastUpdate;
  nsIntRegion mInvalidFront;
  nsIntRegion mInvalidBack;
  nsExpirationState mExpirationState;

  // Copies dirty pixels from the front buffer into the back buffer,
  // and records the copied region in aAddPaintedRegion.
  void ValidateBackBufferFromFront(const nsIntRegion &aDirtyRegion,
                                   nsIntRegion& aAddPaintedRegion);

 * This struct stores all the data necessary to perform a paint so that it
 * doesn't need to be recalculated on every repeated transaction.
struct BasicTiledLayerPaintData {
   * The scroll offset of the content from the nearest ancestor layer that
   * represents scrollable content with a display port set.
  ParentLayerPoint mScrollOffset;

   * The scroll offset of the content from the nearest ancestor layer that
   * represents scrollable content with a display port set, for the last
   * layer update transaction.
  ParentLayerPoint mLastScrollOffset;

   * The transform matrix to go from this layer's Layer units to
   * the scroll ancestor's ParentLayer units. The "scroll ancestor" is
   * the closest ancestor layer which scrolls, and is used to obtain
   * the composition bounds that are relevant for this layer.
  gfx::Matrix4x4 mTransformToCompBounds;

   * The critical displayport of the content from the nearest ancestor layer
   * that represents scrollable content with a display port set. Empty if a
   * critical displayport is not set.
  LayerIntRect mCriticalDisplayPort;

   * The render resolution of the document that the content this layer
   * represents is in.
  CSSToParentLayerScale mResolution;

   * The composition bounds of the layer, in Layer coordinates. This is
   * used to make sure that tiled updates to regions that are visible to the
   * user are grouped coherently.
  LayerRect mCompositionBounds;

   * Low precision updates are always executed a tile at a time in repeated
   * transactions. This counter is set to 1 on the first transaction of a low
   * precision update, and incremented for each subsequent transaction.
  uint16_t mLowPrecisionPaintCount;

   * Whether this is the first time this layer is painting
  bool mFirstPaint : 1;

   * Whether there is further work to complete this paint. This is used to
   * determine whether or not to repeat the transaction when painting
   * progressively.
  bool mPaintFinished : 1;

class SharedFrameMetricsHelper

   * This is called by the BasicTileLayer to determine if it is still interested
   * in the update of this display-port to continue. We can return true here
   * to abort the current update and continue with any subsequent ones. This
   * is useful for slow-to-render pages when the display-port starts lagging
   * behind enough that continuing to draw it is wasted effort.
  bool UpdateFromCompositorFrameMetrics(const LayerMetricsWrapper& aLayer,
                                        bool aHasPendingNewThebesContent,
                                        bool aLowPrecision,
                                        ViewTransform& aViewTransform);

   * Determines if the compositor's upcoming composition bounds has fallen
   * outside of the contents display port. If it has then the compositor
   * will start to checker board. Checker boarding is when the compositor
   * tries to composite a tile and it is not available. Historically
   * a tile with a checker board pattern was used. Now a blank tile is used.
  bool AboutToCheckerboard(const FrameMetrics& aContentMetrics,
                           const FrameMetrics& aCompositorMetrics);
  bool mLastProgressiveUpdateWasLowPrecision;
  bool mProgressiveUpdateWasInDanger;

 * Provide an instance of TiledLayerBuffer backed by drawable TextureClients.
 * This buffer provides an implementation of ValidateTile using a
 * thebes callback and can support painting using a single paint buffer.
 * Whether a single paint buffer is used is controlled by
 * gfxPrefs::PerTileDrawing().
class ClientTiledLayerBuffer
  : public TiledLayerBuffer<ClientTiledLayerBuffer, TileClient>
  friend class TiledLayerBuffer<ClientTiledLayerBuffer, TileClient>;

  ClientTiledLayerBuffer(ClientTiledPaintedLayer* aPaintedLayer,
                         CompositableClient* aCompositableClient,
                         ClientLayerManager* aManager,
                         SharedFrameMetricsHelper* aHelper);
    : mPaintedLayer(nullptr)
    , mCompositableClient(nullptr)
    , mManager(nullptr)
    , mLastPaintContentType(gfxContentType::COLOR)
    , mLastPaintSurfaceMode(SurfaceMode::SURFACE_OPAQUE)
    , mSharedFrameMetricsHelper(nullptr)
    , mTilingOrigin(std::numeric_limits<int32_t>::max(),

  void PaintThebes(const nsIntRegion& aNewValidRegion,
                   const nsIntRegion& aPaintRegion,
                   LayerManager::DrawPaintedLayerCallback aCallback,
                   void* aCallbackData);

  void ReadUnlock();

  void ReadLock();

  void Release();

  void DiscardBuffers();

  const CSSToParentLayerScale& GetFrameResolution() { return mFrameResolution; }

  void SetFrameResolution(const CSSToParentLayerScale& aResolution) { mFrameResolution = aResolution; }

  bool HasFormatChanged() const;

   * Performs a progressive update of a given tiled buffer.
   * See ComputeProgressiveUpdateRegion below for parameter documentation.
  bool ProgressiveUpdate(nsIntRegion& aValidRegion,
                         nsIntRegion& aInvalidRegion,
                         const nsIntRegion& aOldValidRegion,
                         BasicTiledLayerPaintData* aPaintData,
                         LayerManager::DrawPaintedLayerCallback aCallback,
                         void* aCallbackData);

  SurfaceDescriptorTiles GetSurfaceDescriptorTiles();

  TileClient ValidateTile(TileClient aTile,
                          const nsIntPoint& aTileRect,
                          const nsIntRegion& dirtyRect);

  void PostValidate(const nsIntRegion& aPaintRegion);

  void UnlockTile(TileClient aTile);

  void ReleaseTile(TileClient aTile) { aTile.Release(); }

  void SwapTiles(TileClient& aTileA, TileClient& aTileB) { std::swap(aTileA, aTileB); }

  TileClient GetPlaceholderTile() const { return TileClient(); }

  gfxContentType GetContentType(SurfaceMode* aMode = nullptr) const;
  ClientTiledPaintedLayer* mPaintedLayer;
  CompositableClient* mCompositableClient;
  ClientLayerManager* mManager;
  LayerManager::DrawPaintedLayerCallback mCallback;
  void* mCallbackData;
  CSSToParentLayerScale mFrameResolution;
  gfxContentType mLastPaintContentType;
  SurfaceMode mLastPaintSurfaceMode;

  // The region that will be made valid during Update(). Once Update() is
  // completed then this is identical to mValidRegion.
  nsIntRegion mNewValidRegion;

  // The DrawTarget we use when UseSinglePaintBuffer() above is true.
  RefPtr<gfx::DrawTarget>       mSinglePaintDrawTarget;
  nsIntPoint                    mSinglePaintBufferOffset;
  SharedFrameMetricsHelper*  mSharedFrameMetricsHelper;
  // When using Moz2D's CreateTiledDrawTarget we maintain a list of gfx::Tiles
  std::vector<gfx::Tile> mMoz2DTiles;
   * While we're adding tiles, this is used to keep track of the position of
   * the top-left of the top-left-most tile.  When we come to wrap the tiles in
   * TiledDrawTarget we subtract the value of this member from each tile's
   * offset so that all the tiles have a positive offset, then add a
   * translation to the TiledDrawTarget to compensate.  This is important so
   * that the mRect of the TiledDrawTarget is always at a positive x/y
   * position, otherwise its GetSize() methods will be broken.
  gfx::IntPoint mTilingOrigin;
   * Calculates the region to update in a single progressive update transaction.
   * This employs some heuristics to update the most 'sensible' region to
   * update at this point in time, and how large an update should be performed
   * at once to maintain visual coherency.
   * aInvalidRegion is the current invalid region.
   * aOldValidRegion is the valid region of mTiledBuffer at the beginning of the
   * current transaction.
   * aRegionToPaint will be filled with the region to update. This may be empty,
   * which indicates that there is no more work to do.
   * aIsRepeated should be true if this function has already been called during
   * this transaction.
   * Returns true if it should be called again, false otherwise. In the case
   * that aRegionToPaint is empty, this will return aIsRepeated for convenience.
  bool ComputeProgressiveUpdateRegion(const nsIntRegion& aInvalidRegion,
                                      const nsIntRegion& aOldValidRegion,
                                      nsIntRegion& aRegionToPaint,
                                      BasicTiledLayerPaintData* aPaintData,
                                      bool aIsRepeated);

class TiledContentClient : public CompositableClient
  // XXX: for now the layer which owns us interacts directly with our buffers.
  // We should have a content client for each tiled buffer which manages its
  // own valid region, resolution, etc. Then we could have a much cleaner
  // interface and tidy up BasicTiledPaintedLayer::PaintThebes (bug 862547).
  friend class ClientTiledPaintedLayer;

  TiledContentClient(ClientTiledPaintedLayer* aPaintedLayer,
                     ClientLayerManager* aManager);


    mDestroyed = true;

  virtual void PrintInfo(std::stringstream& aStream, const char* aPrefix);

  virtual void Dump(std::stringstream& aStream,
                    const char* aPrefix="",
                    bool aDumpHtml=false);

  virtual TextureInfo GetTextureInfo() const MOZ_OVERRIDE
    return TextureInfo(CompositableType::CONTENT_TILED);

  virtual void ClearCachedResources() MOZ_OVERRIDE;

  enum TiledBufferType {
  void UseTiledLayerBuffer(TiledBufferType aType);

  SharedFrameMetricsHelper mSharedFrameMetricsHelper;
  ClientTiledLayerBuffer mTiledBuffer;
  ClientTiledLayerBuffer mLowPrecisionTiledBuffer;