Refactored usages of old GetDefaultStream() API

Author: Dan Toškan

cpp/open3d/core/CUDAUtils.cpp

@@ -154,7 +154,7 @@ void Synchronize(const CUDAStream& stream) {
 CUDAStream& CUDAStream::GetInstance() {
     // The global stream state is given per thread like CUDA's internal
     // device state.
-    thread_local CUDAStream instance = cuda::GetDefaultStream();
+    thread_local CUDAStream instance = CUDAStream::Default();
     return instance;
 }
 
@@ -188,7 +188,7 @@ void CUDAStream::Set(cudaStream_t stream) { stream_ = stream; }
 void CUDAStream::Destroy() {
     OPEN3D_ASSERT(!IsDefaultStream());
     OPEN3D_CUDA_CHECK(cudaStreamDestroy(stream_));
-    *this = cuda::GetDefaultStream();
+    *this = CUDAStream::Default();
 }
 
 CUDAScopedDevice::CUDAScopedDevice(int device_id)

cpp/open3d/core/CUDAUtils.h

@@ -70,6 +70,13 @@ class CUDAStream {
     /// calling Destroy().
     static CUDAStream CreateNew();
 
+    /// Explicitly constructs a default stream. The default constructor could be
+    /// used, but this is clearer and closer to the old API.
+    static CUDAStream Default() { return {}; }
+
+    /// Default constructor. Refers to the default CUDA stream.
+    CUDAStream() = default;
+
     /// Sets the flag indicating if all memory copy operations done within
     /// this stream from device -> host should be synchronized. True by
     /// default. The default CUDA stream is implicitly synchronized with every
@@ -311,7 +318,6 @@ bool SupportsMemoryPools(const Device& device);
 #ifdef BUILD_CUDA_MODULE
 
 int GetDevice();
-CUDAStream GetDefaultStream();
 
 /// Calls cudaStreamSynchronize() for the specified CUDA stream.
 /// \param stream The stream to be synchronized.

cpp/open3d/core/hashmap/CUDA/StdGPUHashBackend.h

@@ -401,7 +401,7 @@ void StdGPUHashBackend<Key, Hash, Eq>::Allocate(int64_t capacity) {
     // stdgpu initializes on the default stream. Set the current stream to
     // ensure correct behavior.
     {
-        CUDAScopedStream scoped_stream(cuda::GetDefaultStream());
+        CUDAScopedStream scoped_stream(CUDAStream::Default());
 
         impl_ = InternalStdGPUHashBackend<Key, Hash, Eq>::createDeviceObject(
                 this->capacity_,
@@ -419,7 +419,7 @@ void StdGPUHashBackend<Key, Hash, Eq>::Free() {
     // stdgpu initializes on the default stream. Set the current stream to
     // ensure correct behavior.
     {
-        CUDAScopedStream scoped_stream(cuda::GetDefaultStream());
+        CUDAScopedStream scoped_stream(CUDAStream::Default());
 
         InternalStdGPUHashBackend<Key, Hash, Eq>::destroyDeviceObject(impl_);
     }

cpp/tests/core/CUDAUtils.cpp

@@ -45,7 +45,7 @@ void CheckScopedStreamManually() {
     int current_device = core::cuda::GetDevice();
 
     ASSERT_EQ(core::CUDAStream::GetInstance().Get(),
-              core::cuda::GetDefaultStream().Get());
+              core::CUDAStream::Default().Get());
     ASSERT_EQ(core::cuda::GetDevice(), current_device);
 
     core::CUDAStream stream = core::CUDAStream::CreateNew();
@@ -68,20 +68,20 @@ void CheckScopedStreamAutomatically() {
     int current_device = core::cuda::GetDevice();
 
     ASSERT_EQ(core::CUDAStream::GetInstance().Get(),
-              core::cuda::GetDefaultStream());
+              core::CUDAStream::Default());
     ASSERT_EQ(core::cuda::GetDevice(), current_device);
 
     {
         core::CUDAScopedStream scoped_stream(
                 core::CUDAScopedStream::CreateNewStream);
 
         ASSERT_NE(core::CUDAStream::GetInstance().Get(),
-                  core::cuda::GetDefaultStream());
+                  core::CUDAStream::Default());
         ASSERT_EQ(core::cuda::GetDevice(), current_device);
     }
 
     ASSERT_EQ(core::CUDAStream::GetInstance().Get(),
-              core::cuda::GetDefaultStream());
+              core::CUDAStream::Default());
     ASSERT_EQ(core::cuda::GetDevice(), current_device);
 }