stream to scatter kernels

cuda/scatter_kernel.cu

 #include <ATen/ATen.h>
+#include <ATen/cuda/CUDAContext.h>
 #include <ATen/cuda/detail/IndexUtils.cuh>
 #include <ATen/cuda/detail/TensorInfo.cuh>
 
@@ -8,20 +9,23 @@
 #define THREADS 1024
 #define BLOCKS(N) (N + THREADS - 1) / THREADS
 
+auto stream = at::cuda::getCurrentCUDAStream();
+
 #define KERNEL_RUN(NAME, DIMS, N, ...)                                         \
   [&] {                                                                        \
+    auto stream = at::cuda::getCurrentCUDAStream();                            \
     switch (DIMS) {                                                            \
     case 1:                                                                    \
-      NAME<scalar_t, 1><<<BLOCKS(N), THREADS>>>(__VA_ARGS__, N);               \
+      NAME<scalar_t, 1><<<BLOCKS(N), THREADS, 0, stream>>>(__VA_ARGS__, N);    \
       break;                                                                   \
     case 2:                                                                    \
-      NAME<scalar_t, 2><<<BLOCKS(N), THREADS>>>(__VA_ARGS__, N);               \
+      NAME<scalar_t, 2><<<BLOCKS(N), THREADS, 0, stream>>>(__VA_ARGS__, N);    \
       break;                                                                   \
     case 3:                                                                    \
-      NAME<scalar_t, 3><<<BLOCKS(N), THREADS>>>(__VA_ARGS__, N);               \
+      NAME<scalar_t, 3><<<BLOCKS(N), THREADS, 0, stream>>>(__VA_ARGS__, N);    \
       break;                                                                   \
     default:                                                                   \
-      NAME<scalar_t, -1><<<BLOCKS(N), THREADS>>>(__VA_ARGS__, N);              \
+      NAME<scalar_t, -1><<<BLOCKS(N), THREADS, 0, stream>>>(__VA_ARGS__, N);   \
     }                                                                          \
   }()
 
@@ -43,7 +47,6 @@ scatter_mul_kernel(at::cuda::detail::TensorInfo<scalar_t, int64_t> src,
 
 void scatter_mul_cuda(at::Tensor src, at::Tensor index, at::Tensor out,
                       int64_t dim) {
-  cudaSetDevice(src.get_device());
   AT_DISPATCH_ALL_TYPES(src.scalar_type(), "scatter_mul_kernel", [&] {
     KERNEL_RUN(scatter_mul_kernel, index.dim(), index.numel(),
                at::cuda::detail::getTensorInfo<scalar_t, int64_t>(src),
@@ -70,7 +73,6 @@ scatter_div_kernel(at::cuda::detail::TensorInfo<scalar_t, int64_t> src,
 
 void scatter_div_cuda(at::Tensor src, at::Tensor index, at::Tensor out,
                       int64_t dim) {
-  cudaSetDevice(src.get_device());
   AT_DISPATCH_ALL_TYPES(src.scalar_type(), "scatter_div_kernel", [&] {
     KERNEL_RUN(scatter_div_kernel, index.dim(), index.numel(),
                at::cuda::detail::getTensorInfo<scalar_t, int64_t>(src),
@@ -116,7 +118,6 @@ scatter_max_kernel(at::cuda::detail::TensorInfo<scalar_t, int64_t> src,
 
 void scatter_max_cuda(at::Tensor src, at::Tensor index, at::Tensor out,
                       at::Tensor arg, int64_t dim) {
-  cudaSetDevice(src.get_device());
   AT_DISPATCH_ALL_TYPES(src.scalar_type(), "scatter_max_kernel", [&] {
     auto src_info = at::cuda::detail::getTensorInfo<scalar_t, int64_t>(src);
     auto index_info = at::cuda::detail::getTensorInfo<int64_t, int64_t>(index);
@@ -147,7 +148,6 @@ scatter_min_kernel(at::cuda::detail::TensorInfo<scalar_t, int64_t> src,
 
 void scatter_min_cuda(at::Tensor src, at::Tensor index, at::Tensor out,
                       at::Tensor arg, int64_t dim) {
-  cudaSetDevice(src.get_device());
   AT_DISPATCH_ALL_TYPES(src.scalar_type(), "scatter_min_kernel", [&] {
     auto src_info = at::cuda::detail::getTensorInfo<scalar_t, int64_t>(src);
     auto index_info = at::cuda::detail::getTensorInfo<int64_t, int64_t>(index);