gfx/layers/ipc/CrossProcessCompositorBridgeParent.cpp
author Cosmin Sabou <csabou@mozilla.com>
Sat, 19 Jan 2019 11:57:49 +0200
changeset 454597 f90bab5af97efa714181eea7fad45cf8cf14e3ea
parent 454462 e3a8a7245f627e6697056a18847f286c0a1d2bc9
parent 454520 5f4630838d46dd81dadb13220a4af0da9e23a619
child 459686 26fb2a868911021c586ca56d64ede136ae28c015
permissions -rw-r--r--
Merge mozilla-inbound to mozilla-central. a=merge

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* 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 http://mozilla.org/MPL/2.0/. */

#include "mozilla/layers/CrossProcessCompositorBridgeParent.h"

#include <stdint.h>  // for uint64_t

#include "LayerTransactionParent.h"   // for LayerTransactionParent
#include "apz/src/APZCTreeManager.h"  // for APZCTreeManager
#include "base/message_loop.h"        // for MessageLoop
#include "base/task.h"                // for CancelableTask, etc
#include "base/thread.h"              // for Thread
#ifdef XP_WIN
#  include "mozilla/gfx/DeviceManagerDx.h"  // for DeviceManagerDx
#endif
#include "mozilla/ipc/Transport.h"           // for Transport
#include "mozilla/layers/AnimationHelper.h"  // for CompositorAnimationStorage
#include "mozilla/layers/APZCTreeManagerParent.h"  // for APZCTreeManagerParent
#include "mozilla/layers/APZUpdater.h"             // for APZUpdater
#include "mozilla/layers/AsyncCompositionManager.h"
#include "mozilla/layers/CompositorOptions.h"
#include "mozilla/layers/CompositorThread.h"
#include "mozilla/layers/LayerManagerComposite.h"
#include "mozilla/layers/LayerTreeOwnerTracker.h"
#include "mozilla/layers/PLayerTransactionParent.h"
#include "mozilla/layers/RemoteContentController.h"
#include "mozilla/layers/WebRenderBridgeParent.h"
#include "mozilla/layers/AsyncImagePipelineManager.h"
#include "mozilla/mozalloc.h"  // for operator new, etc
#include "nsDebug.h"           // for NS_ASSERTION, etc
#include "nsTArray.h"          // for nsTArray
#include "nsXULAppAPI.h"       // for XRE_GetIOMessageLoop
#include "mozilla/Unused.h"
#include "mozilla/StaticPtr.h"

using namespace std;

namespace mozilla {

namespace layers {

// defined in CompositorBridgeParent.cpp
typedef map<LayersId, CompositorBridgeParent::LayerTreeState> LayerTreeMap;
extern LayerTreeMap sIndirectLayerTrees;
extern StaticAutoPtr<mozilla::Monitor> sIndirectLayerTreesLock;
void UpdateIndirectTree(LayersId aId, Layer* aRoot,
                        const TargetConfig& aTargetConfig);
void EraseLayerState(LayersId aId);

mozilla::ipc::IPCResult
CrossProcessCompositorBridgeParent::RecvRequestNotifyAfterRemotePaint() {
  mNotifyAfterRemotePaint = true;
  return IPC_OK();
}

void CrossProcessCompositorBridgeParent::ActorDestroy(ActorDestroyReason aWhy) {
  mCanSend = false;

  // We must keep this object alive untill the code handling message
  // reception is finished on this thread.
  MessageLoop::current()->PostTask(NewRunnableMethod(
      "layers::CrossProcessCompositorBridgeParent::DeferredDestroy", this,
      &CrossProcessCompositorBridgeParent::DeferredDestroy));
}

PLayerTransactionParent*
CrossProcessCompositorBridgeParent::AllocPLayerTransactionParent(
    const nsTArray<LayersBackend>&, const LayersId& aId) {
  MOZ_ASSERT(aId.IsValid());

  // Check to see if this child process has access to this layer tree.
  if (!LayerTreeOwnerTracker::Get()->IsMapped(aId, OtherPid())) {
    NS_ERROR(
        "Unexpected layers id in AllocPLayerTransactionParent; dropping "
        "message...");
    return nullptr;
  }

  MonitorAutoLock lock(*sIndirectLayerTreesLock);

  CompositorBridgeParent::LayerTreeState* state = nullptr;
  LayerTreeMap::iterator itr = sIndirectLayerTrees.find(aId);
  if (sIndirectLayerTrees.end() != itr) {
    state = &itr->second;
  }

  if (state && state->mLayerManager) {
    state->mCrossProcessParent = this;
    HostLayerManager* lm = state->mLayerManager;
    CompositorAnimationStorage* animStorage =
        state->mParent ? state->mParent->GetAnimationStorage() : nullptr;
    TimeDuration vsyncRate =
        state->mParent ? state->mParent->GetVsyncInterval() : TimeDuration();
    LayerTransactionParent* p =
        new LayerTransactionParent(lm, this, animStorage, aId, vsyncRate);
    p->AddIPDLReference();
    sIndirectLayerTrees[aId].mLayerTree = p;
    return p;
  }

  NS_WARNING("Created child without a matching parent?");
  LayerTransactionParent* p = new LayerTransactionParent(
      /* aManager */ nullptr, this, /* aAnimStorage */ nullptr, aId,
      TimeDuration());
  p->AddIPDLReference();
  return p;
}

bool CrossProcessCompositorBridgeParent::DeallocPLayerTransactionParent(
    PLayerTransactionParent* aLayers) {
  LayerTransactionParent* slp = static_cast<LayerTransactionParent*>(aLayers);
  EraseLayerState(slp->GetId());
  static_cast<LayerTransactionParent*>(aLayers)->ReleaseIPDLReference();
  return true;
}

PAPZCTreeManagerParent*
CrossProcessCompositorBridgeParent::AllocPAPZCTreeManagerParent(
    const LayersId& aLayersId) {
  // Check to see if this child process has access to this layer tree.
  if (!LayerTreeOwnerTracker::Get()->IsMapped(aLayersId, OtherPid())) {
    NS_ERROR(
        "Unexpected layers id in AllocPAPZCTreeManagerParent; dropping "
        "message...");
    return nullptr;
  }

  MonitorAutoLock lock(*sIndirectLayerTreesLock);
  CompositorBridgeParent::LayerTreeState& state =
      sIndirectLayerTrees[aLayersId];

  // If the widget has shutdown its compositor, we may not have had a chance yet
  // to unmap our layers id, and we could get here without a parent compositor.
  // In this case return an empty APZCTM.
  if (!state.mParent) {
    // Note: we immediately call ClearTree since otherwise the APZCTM will
    // retain a reference to itself, through the checkerboard observer.
    LayersId dummyId{0};
    RefPtr<APZCTreeManager> temp = new APZCTreeManager(dummyId);
    RefPtr<APZUpdater> tempUpdater = new APZUpdater(temp, false);
    tempUpdater->ClearTree(dummyId);
    return new APZCTreeManagerParent(aLayersId, temp, tempUpdater);
  }

  state.mParent->AllocateAPZCTreeManagerParent(lock, aLayersId, state);
  return state.mApzcTreeManagerParent;
}
bool CrossProcessCompositorBridgeParent::DeallocPAPZCTreeManagerParent(
    PAPZCTreeManagerParent* aActor) {
  APZCTreeManagerParent* parent = static_cast<APZCTreeManagerParent*>(aActor);

  MonitorAutoLock lock(*sIndirectLayerTreesLock);
  auto iter = sIndirectLayerTrees.find(parent->GetLayersId());
  if (iter != sIndirectLayerTrees.end()) {
    CompositorBridgeParent::LayerTreeState& state = iter->second;
    MOZ_ASSERT(state.mApzcTreeManagerParent == parent);
    state.mApzcTreeManagerParent = nullptr;
  }

  delete parent;

  return true;
}

PAPZParent* CrossProcessCompositorBridgeParent::AllocPAPZParent(
    const LayersId& aLayersId) {
  // Check to see if this child process has access to this layer tree.
  if (!LayerTreeOwnerTracker::Get()->IsMapped(aLayersId, OtherPid())) {
    NS_ERROR("Unexpected layers id in AllocPAPZParent; dropping message...");
    return nullptr;
  }

  RemoteContentController* controller = new RemoteContentController();

  // Increment the controller's refcount before we return it. This will keep the
  // controller alive until it is released by IPDL in DeallocPAPZParent.
  controller->AddRef();

  MonitorAutoLock lock(*sIndirectLayerTreesLock);
  CompositorBridgeParent::LayerTreeState& state =
      sIndirectLayerTrees[aLayersId];
  MOZ_ASSERT(!state.mController);
  state.mController = controller;

  return controller;
}

bool CrossProcessCompositorBridgeParent::DeallocPAPZParent(PAPZParent* aActor) {
  RemoteContentController* controller =
      static_cast<RemoteContentController*>(aActor);
  controller->Release();
  return true;
}

PWebRenderBridgeParent*
CrossProcessCompositorBridgeParent::AllocPWebRenderBridgeParent(
    const wr::PipelineId& aPipelineId, const LayoutDeviceIntSize& aSize) {
#ifndef MOZ_BUILD_WEBRENDER
  // Extra guard since this in the parent process and we don't want a malicious
  // child process invoking this codepath before it's ready
  MOZ_RELEASE_ASSERT(false);
#endif
  LayersId layersId = wr::AsLayersId(aPipelineId);
  // Check to see if this child process has access to this layer tree.
  if (!LayerTreeOwnerTracker::Get()->IsMapped(layersId, OtherPid())) {
    NS_ERROR(
        "Unexpected layers id in AllocPWebRenderBridgeParent; dropping "
        "message...");
    return nullptr;
  }

  RefPtr<CompositorBridgeParent> cbp = nullptr;
  RefPtr<WebRenderBridgeParent> root = nullptr;

  {  // scope lock
    MonitorAutoLock lock(*sIndirectLayerTreesLock);
    MOZ_ASSERT(sIndirectLayerTrees.find(layersId) != sIndirectLayerTrees.end());
    MOZ_ASSERT(sIndirectLayerTrees[layersId].mWrBridge == nullptr);
    cbp = sIndirectLayerTrees[layersId].mParent;
    if (cbp) {
      root = sIndirectLayerTrees[cbp->RootLayerTreeId()].mWrBridge;
    }
  }

  RefPtr<wr::WebRenderAPI> api;
  if (root) {
    api = root->GetWebRenderAPI();
  }

  if (!root || !api) {
    // This could happen when this function is called after
    // CompositorBridgeParent destruction. This was observed during Tab move
    // between different windows.
    NS_WARNING(
        nsPrintfCString("Created child without a matching parent? root %p",
                        root.get())
            .get());
    WebRenderBridgeParent* parent =
        WebRenderBridgeParent::CreateDestroyed(aPipelineId);
    parent->AddRef();  // IPDL reference
    return parent;
  }

  api = api->Clone();
  RefPtr<AsyncImagePipelineManager> holder = root->AsyncImageManager();
  RefPtr<CompositorAnimationStorage> animStorage = cbp->GetAnimationStorage();
  WebRenderBridgeParent* parent = new WebRenderBridgeParent(
      this, aPipelineId, nullptr, root->CompositorScheduler(), std::move(api),
      std::move(holder), std::move(animStorage), cbp->GetVsyncInterval());
  parent->AddRef();  // IPDL reference

  {  // scope lock
    MonitorAutoLock lock(*sIndirectLayerTreesLock);
    sIndirectLayerTrees[layersId].mCrossProcessParent = this;
    sIndirectLayerTrees[layersId].mWrBridge = parent;
  }

  return parent;
}

bool CrossProcessCompositorBridgeParent::DeallocPWebRenderBridgeParent(
    PWebRenderBridgeParent* aActor) {
#ifndef MOZ_BUILD_WEBRENDER
  // Extra guard since this in the parent process and we don't want a malicious
  // child process invoking this codepath before it's ready
  MOZ_RELEASE_ASSERT(false);
#endif
  WebRenderBridgeParent* parent = static_cast<WebRenderBridgeParent*>(aActor);
  EraseLayerState(wr::AsLayersId(parent->PipelineId()));
  parent->Release();  // IPDL reference
  return true;
}

mozilla::ipc::IPCResult
CrossProcessCompositorBridgeParent::RecvNotifyChildCreated(
    const LayersId& child, CompositorOptions* aOptions) {
  MonitorAutoLock lock(*sIndirectLayerTreesLock);
  for (LayerTreeMap::iterator it = sIndirectLayerTrees.begin();
       it != sIndirectLayerTrees.end(); it++) {
    CompositorBridgeParent::LayerTreeState* lts = &it->second;
    if (lts->mParent && lts->mCrossProcessParent == this) {
      lts->mParent->NotifyChildCreated(child);
      *aOptions = lts->mParent->GetOptions();
      return IPC_OK();
    }
  }
  return IPC_FAIL_NO_REASON(this);
}

mozilla::ipc::IPCResult
CrossProcessCompositorBridgeParent::RecvMapAndNotifyChildCreated(
    const LayersId& child, const base::ProcessId& pid,
    CompositorOptions* aOptions) {
  // This can only be called from the browser process, as the mapping
  // ensures proper window ownership of layer trees.
  return IPC_FAIL_NO_REASON(this);
}

mozilla::ipc::IPCResult
CrossProcessCompositorBridgeParent::RecvCheckContentOnlyTDR(
    const uint32_t& sequenceNum, bool* isContentOnlyTDR) {
  *isContentOnlyTDR = false;
#ifdef XP_WIN
  ContentDeviceData compositor;

  DeviceManagerDx* dm = DeviceManagerDx::Get();

  // Check that the D3D11 device sequence numbers match.
  D3D11DeviceStatus status;
  dm->ExportDeviceInfo(&status);

  if (sequenceNum == status.sequenceNumber() && !dm->HasDeviceReset()) {
    *isContentOnlyTDR = true;
  }

#endif
  return IPC_OK();
};

void CrossProcessCompositorBridgeParent::ShadowLayersUpdated(
    LayerTransactionParent* aLayerTree, const TransactionInfo& aInfo,
    bool aHitTestUpdate) {
  LayersId id = aLayerTree->GetId();

  MOZ_ASSERT(id.IsValid());

  CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(id);
  if (!state) {
    return;
  }
  MOZ_ASSERT(state->mParent);
  state->mParent->ScheduleRotationOnCompositorThread(aInfo.targetConfig(),
                                                     aInfo.isFirstPaint());

  Layer* shadowRoot = aLayerTree->GetRoot();
  if (shadowRoot) {
    CompositorBridgeParent::SetShadowProperties(shadowRoot);
  }
  UpdateIndirectTree(id, shadowRoot, aInfo.targetConfig());

  // Cache the plugin data for this remote layer tree
  state->mPluginData = aInfo.plugins();
  state->mUpdatedPluginDataAvailable = true;

  state->mParent->NotifyShadowTreeTransaction(
      id, aInfo.isFirstPaint(), aInfo.focusTarget(), aInfo.scheduleComposite(),
      aInfo.paintSequenceNumber(), aInfo.isRepeatTransaction(), aHitTestUpdate);

  // Send the 'remote paint ready' message to the content thread if it has
  // already asked.
  if (mNotifyAfterRemotePaint) {
    Unused << SendRemotePaintIsReady();
    mNotifyAfterRemotePaint = false;
  }

  if (aLayerTree->ShouldParentObserveEpoch()) {
    // Note that we send this through the window compositor, since this needs
    // to reach the widget owning the tab.
    Unused << state->mParent->SendObserveLayersUpdate(
        id, aLayerTree->GetChildEpoch(), true);
  }

  auto endTime = TimeStamp::Now();
#ifdef MOZ_GECKO_PROFILER
  if (profiler_is_active()) {
    class ContentBuildPayload : public ProfilerMarkerPayload {
     public:
      ContentBuildPayload(const mozilla::TimeStamp& aStartTime,
                          const mozilla::TimeStamp& aEndTime)
          : ProfilerMarkerPayload(aStartTime, aEndTime) {}
      virtual void StreamPayload(SpliceableJSONWriter& aWriter,
                                 const TimeStamp& aProcessStartTime,
                                 UniqueStacks& aUniqueStacks) override {
        StreamCommonProps("CONTENT_FULL_PAINT_TIME", aWriter, aProcessStartTime,
                          aUniqueStacks);
      }
    };
    profiler_add_marker_for_thread(
        profiler_current_thread_id(),
        js::ProfilingStackFrame::Category::GRAPHICS, "CONTENT_FULL_PAINT_TIME",
        MakeUnique<ContentBuildPayload>(aInfo.transactionStart(), endTime));
  }
#endif
  Telemetry::Accumulate(
      Telemetry::CONTENT_FULL_PAINT_TIME,
      static_cast<uint32_t>(
          (endTime - aInfo.transactionStart()).ToMilliseconds()));

  RegisterPayload(aLayerTree, aInfo.payload());

  aLayerTree->SetPendingTransactionId(
      aInfo.id(), aInfo.vsyncId(), aInfo.vsyncStart(), aInfo.refreshStart(),
      aInfo.transactionStart(), endTime, aInfo.containsSVG(), aInfo.url(),
      aInfo.fwdTime());
}

void CrossProcessCompositorBridgeParent::DidCompositeLocked(
    LayersId aId, const VsyncId& aVsyncId, TimeStamp& aCompositeStart,
    TimeStamp& aCompositeEnd) {
  sIndirectLayerTreesLock->AssertCurrentThreadOwns();
  if (LayerTransactionParent* layerTree = sIndirectLayerTrees[aId].mLayerTree) {
    TransactionId transactionId =
        layerTree->FlushTransactionId(aVsyncId, aCompositeEnd);
    if (transactionId.IsValid()) {
      Unused << SendDidComposite(aId, transactionId, aCompositeStart,
                                 aCompositeEnd);
    }
  } else if (sIndirectLayerTrees[aId].mWrBridge) {
    MOZ_ASSERT(false);  // this should never get called for a WR compositor
  }
}

void CrossProcessCompositorBridgeParent::ScheduleComposite(
    LayerTransactionParent* aLayerTree) {
  LayersId id = aLayerTree->GetId();
  MOZ_ASSERT(id.IsValid());
  CompositorBridgeParent* parent;
  {  // scope lock
    MonitorAutoLock lock(*sIndirectLayerTreesLock);
    parent = sIndirectLayerTrees[id].mParent;
  }
  if (parent) {
    parent->ScheduleComposite(aLayerTree);
  }
}

void CrossProcessCompositorBridgeParent::NotifyClearCachedResources(
    LayerTransactionParent* aLayerTree) {
  LayersId id = aLayerTree->GetId();
  MOZ_ASSERT(id.IsValid());

  const CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(id);
  if (state && state->mParent) {
    // Note that we send this through the window compositor, since this needs
    // to reach the widget owning the tab.
    Unused << state->mParent->SendObserveLayersUpdate(
        id, aLayerTree->GetChildEpoch(), false);
  }
}

bool CrossProcessCompositorBridgeParent::SetTestSampleTime(
    const LayersId& aId, const TimeStamp& aTime) {
  MOZ_ASSERT(aId.IsValid());
  const CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(aId);
  if (!state) {
    return false;
  }

  MOZ_ASSERT(state->mParent);
  return state->mParent->SetTestSampleTime(aId, aTime);
}

void CrossProcessCompositorBridgeParent::LeaveTestMode(const LayersId& aId) {
  MOZ_ASSERT(aId.IsValid());
  const CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(aId);
  if (!state) {
    return;
  }

  MOZ_ASSERT(state->mParent);
  state->mParent->LeaveTestMode(aId);
}

void CrossProcessCompositorBridgeParent::ApplyAsyncProperties(
    LayerTransactionParent* aLayerTree, TransformsToSkip aSkip) {
  LayersId id = aLayerTree->GetId();
  MOZ_ASSERT(id.IsValid());
  const CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(id);
  if (!state) {
    return;
  }

  MOZ_ASSERT(state->mParent);
  state->mParent->ApplyAsyncProperties(aLayerTree, aSkip);
}

void CrossProcessCompositorBridgeParent::SetTestAsyncScrollOffset(
    const LayersId& aLayersId, const ScrollableLayerGuid::ViewID& aScrollId,
    const CSSPoint& aPoint) {
  MOZ_ASSERT(aLayersId.IsValid());
  const CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(aLayersId);
  if (!state) {
    return;
  }

  MOZ_ASSERT(state->mParent);
  state->mParent->SetTestAsyncScrollOffset(aLayersId, aScrollId, aPoint);
}

void CrossProcessCompositorBridgeParent::SetTestAsyncZoom(
    const LayersId& aLayersId, const ScrollableLayerGuid::ViewID& aScrollId,
    const LayerToParentLayerScale& aZoom) {
  MOZ_ASSERT(aLayersId.IsValid());
  const CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(aLayersId);
  if (!state) {
    return;
  }

  MOZ_ASSERT(state->mParent);
  state->mParent->SetTestAsyncZoom(aLayersId, aScrollId, aZoom);
}

void CrossProcessCompositorBridgeParent::FlushApzRepaints(
    const LayersId& aLayersId) {
  MOZ_ASSERT(aLayersId.IsValid());
  const CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(aLayersId);
  if (!state || !state->mParent) {
    return;
  }

  state->mParent->FlushApzRepaints(aLayersId);
}

void CrossProcessCompositorBridgeParent::GetAPZTestData(
    const LayersId& aLayersId, APZTestData* aOutData) {
  MOZ_ASSERT(aLayersId.IsValid());
  const CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(aLayersId);
  if (!state || !state->mParent) {
    return;
  }

  state->mParent->GetAPZTestData(aLayersId, aOutData);
}

void CrossProcessCompositorBridgeParent::SetConfirmedTargetAPZC(
    const LayersId& aLayersId, const uint64_t& aInputBlockId,
    const nsTArray<ScrollableLayerGuid>& aTargets) {
  MOZ_ASSERT(aLayersId.IsValid());
  const CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(aLayersId);
  if (!state || !state->mParent) {
    return;
  }

  state->mParent->SetConfirmedTargetAPZC(aLayersId, aInputBlockId, aTargets);
}

AsyncCompositionManager*
CrossProcessCompositorBridgeParent::GetCompositionManager(
    LayerTransactionParent* aLayerTree) {
  LayersId id = aLayerTree->GetId();
  const CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(id);
  if (!state) {
    return nullptr;
  }

  MOZ_ASSERT(state->mParent);
  return state->mParent->GetCompositionManager(aLayerTree);
}

void CrossProcessCompositorBridgeParent::DeferredDestroy() {
  mSelfRef = nullptr;
}

CrossProcessCompositorBridgeParent::~CrossProcessCompositorBridgeParent() {
  MOZ_ASSERT(XRE_GetIOMessageLoop());
}

PTextureParent* CrossProcessCompositorBridgeParent::AllocPTextureParent(
    const SurfaceDescriptor& aSharedData, const ReadLockDescriptor& aReadLock,
    const LayersBackend& aLayersBackend, const TextureFlags& aFlags,
    const LayersId& aId, const uint64_t& aSerial,
    const wr::MaybeExternalImageId& aExternalImageId) {
  CompositorBridgeParent::LayerTreeState* state = nullptr;

  LayerTreeMap::iterator itr = sIndirectLayerTrees.find(aId);
  if (sIndirectLayerTrees.end() != itr) {
    state = &itr->second;
  }

  TextureFlags flags = aFlags;

  LayersBackend actualBackend = LayersBackend::LAYERS_NONE;
  if (state && state->mLayerManager) {
    actualBackend = state->mLayerManager->GetBackendType();
  }

  if (!state) {
    // The compositor was recreated, and we're receiving layers updates for a
    // a layer manager that will soon be discarded or invalidated. We can't
    // return null because this will mess up deserialization later and we'll
    // kill the content process. Instead, we signal that the underlying
    // TextureHost should not attempt to access the compositor.
    flags |= TextureFlags::INVALID_COMPOSITOR;
  } else if (actualBackend != LayersBackend::LAYERS_NONE &&
             aLayersBackend != actualBackend) {
    gfxDevCrash(gfx::LogReason::PAllocTextureBackendMismatch)
        << "Texture backend is wrong";
  }

  return TextureHost::CreateIPDLActor(this, aSharedData, aReadLock,
                                      aLayersBackend, aFlags, aSerial,
                                      aExternalImageId);
}

bool CrossProcessCompositorBridgeParent::DeallocPTextureParent(
    PTextureParent* actor) {
  return TextureHost::DestroyIPDLActor(actor);
}

bool CrossProcessCompositorBridgeParent::IsSameProcess() const {
  return OtherPid() == base::GetCurrentProcId();
}

void CrossProcessCompositorBridgeParent::UpdatePaintTime(
    LayerTransactionParent* aLayerTree, const TimeDuration& aPaintTime) {
  LayersId id = aLayerTree->GetId();
  MOZ_ASSERT(id.IsValid());

  CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(id);
  if (!state || !state->mParent) {
    return;
  }

  state->mParent->UpdatePaintTime(aLayerTree, aPaintTime);
}

void CrossProcessCompositorBridgeParent::RegisterPayload(
    LayerTransactionParent* aLayerTree,
    const InfallibleTArray<CompositionPayload>& aPayload) {
  LayersId id = aLayerTree->GetId();
  MOZ_ASSERT(id.IsValid());

  CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(id);
  if (!state || !state->mParent) {
    return;
  }

  state->mParent->RegisterPayload(aLayerTree, aPayload);
}

void CrossProcessCompositorBridgeParent::ObserveLayersUpdate(
    LayersId aLayersId, LayersObserverEpoch aEpoch, bool aActive) {
  MOZ_ASSERT(aLayersId.IsValid());

  CompositorBridgeParent::LayerTreeState* state =
      CompositorBridgeParent::GetIndirectShadowTree(aLayersId);
  if (!state || !state->mParent) {
    return;
  }

  Unused << state->mParent->SendObserveLayersUpdate(aLayersId, aEpoch, aActive);
}

}  // namespace layers
}  // namespace mozilla