Prevent race condition if multiple threads create identical D3D12 object

* We use HasWrapper() to deduplicate D3D12 objects which must not be created as
  duplicates, but we need to ensure that checking for existing wrappers and
  adding a new one all happens atomically with respect to other checks.

renderdoc/driver/d3d12/d3d12_device.cpp

@@ -1172,6 +1172,8 @@ IUnknown *WrappedID3D12Device::WrapSwapchainBuffer(IDXGISwapper *swapper, DXGI_F
 
 IDXGIResource *WrappedID3D12Device::WrapExternalDXGIResource(IDXGIResource *res)
 {
+  SCOPED_LOCK(m_WrapDeduplicateLock);
+
   ID3D12Resource *d3d12res;
   res->QueryInterface(__uuidof(ID3D12Resource), (void **)&d3d12res);
   if(GetResourceManager()->HasWrapper(d3d12res))

renderdoc/driver/d3d12/d3d12_device.h

@@ -403,6 +403,8 @@ private:
   Threading::CriticalSection m_MapsLock;
   rdcarray<MapState> m_Maps;
 
+  Threading::CriticalSection m_WrapDeduplicateLock;
+
   bool ProcessChunk(ReadSerialiser &ser, D3D12Chunk context);
 
   unsigned int m_InternalRefcount;

renderdoc/driver/d3d12/d3d12_device_wrap.cpp

@@ -949,17 +949,23 @@ HRESULT WrappedID3D12Device::CreateRootSignature(UINT nodeMask, const void *pBlo
 
   if(SUCCEEDED(ret))
   {
-    // duplicate signatures can be returned, if Create is called with a previous equivalent blob
-    if(GetResourceManager()->HasWrapper(real))
-    {
-      real->Release();
-      ID3D12RootSignature *existing = (ID3D12RootSignature *)GetResourceManager()->GetWrapper(real);
-      existing->AddRef();
-      *ppvRootSignature = existing;
-      return ret;
-    }
+    WrappedID3D12RootSignature *wrapped = NULL;
 
-    WrappedID3D12RootSignature *wrapped = new WrappedID3D12RootSignature(real, this);
+    {
+      SCOPED_LOCK(m_WrapDeduplicateLock);
+
+      // duplicate signatures can be returned, if Create is called with a previous equivalent blob
+      if(GetResourceManager()->HasWrapper(real))
+      {
+        real->Release();
+        ID3D12RootSignature *existing = (ID3D12RootSignature *)GetResourceManager()->GetWrapper(real);
+        existing->AddRef();
+        *ppvRootSignature = existing;
+        return ret;
+      }
+
+      wrapped = new WrappedID3D12RootSignature(real, this);
+    }
 
     if(IsCaptureMode(m_State))
     {
@@ -2013,17 +2019,23 @@ HRESULT WrappedID3D12Device::CreateCommandSignature(const D3D12_COMMAND_SIGNATUR
 
   if(SUCCEEDED(ret))
   {
-    if(GetResourceManager()->HasWrapper(real))
-    {
-      real->Release();
-      ID3D12CommandSignature *existing =
-          (ID3D12CommandSignature *)GetResourceManager()->GetWrapper(real);
-      existing->AddRef();
-      *ppvCommandSignature = existing;
-      return ret;
-    }
+    WrappedID3D12CommandSignature *wrapped = NULL;
 
-    WrappedID3D12CommandSignature *wrapped = new WrappedID3D12CommandSignature(real, this);
+    {
+      SCOPED_LOCK(m_WrapDeduplicateLock);
+
+      if(GetResourceManager()->HasWrapper(real))
+      {
+        real->Release();
+        ID3D12CommandSignature *existing =
+            (ID3D12CommandSignature *)GetResourceManager()->GetWrapper(real);
+        existing->AddRef();
+        *ppvCommandSignature = existing;
+        return ret;
+      }
+
+      wrapped = new WrappedID3D12CommandSignature(real, this);
+    }
 
     if(IsCaptureMode(m_State))
     {

renderdoc/driver/d3d12/d3d12_device_wrap4.cpp

@@ -504,9 +504,21 @@ D3D12_RESOURCE_ALLOCATION_INFO WrappedID3D12Device::GetResourceAllocationInfo1(
 
 ID3D12Fence *WrappedID3D12Device::CreateProtectedSessionFence(ID3D12Fence *real)
 {
-  // we basically treat this kind of like CreateFence and serialise it as such, and guess at the
-  // parameters to CreateFence.
-  WrappedID3D12Fence1 *wrapped = new WrappedID3D12Fence1(real, this);
+  WrappedID3D12Fence1 *wrapped = NULL;
+
+  {
+    SCOPED_LOCK(m_WrapDeduplicateLock);
+
+    // if we already have this fence wrapped, return the existing wrapper
+    if(GetResourceManager()->HasWrapper(real))
+    {
+      return (ID3D12Fence *)GetResourceManager()->GetWrapper((ID3D12DeviceChild *)real);
+    }
+
+    // we basically treat this kind of like CreateFence and serialise it as such, and guess at the
+    // parameters to CreateFence.
+    wrapped = new WrappedID3D12Fence1(real, this);
+  }
 
   if(IsCaptureMode(m_State))
   {

renderdoc/driver/d3d12/d3d12_resources.h

@@ -521,15 +521,6 @@ public:
     else if(riid == __uuidof(ID3D12Fence1))
       fence = (ID3D12Fence *)(ID3D12Fence1 *)iface;
 
-    // if we already have this fence wrapped, return the existing wrapper
-    if(m_pDevice->GetResourceManager()->HasWrapper(fence))
-    {
-      *ppFence =
-          (ID3D12Fence *)m_pDevice->GetResourceManager()->GetWrapper((ID3D12DeviceChild *)fence);
-      return S_OK;
-    }
-
-    // if not, record its creation
     *ppFence = m_pDevice->CreateProtectedSessionFence(fence);
     return S_OK;
   }