diff --git a/sgl-kernel/csrc/cpu/interface.cpp b/sgl-kernel/csrc/cpu/interface.cpp
index 969a6bad4ed..9057a50f4a2 100644
--- a/sgl-kernel/csrc/cpu/interface.cpp
+++ b/sgl-kernel/csrc/cpu/interface.cpp
@@ -47,71 +47,26 @@ void initialize(int64_t size, int64_t rank) {
   }
 }
 
-void shm_allreduce(
-    torch::Tensor& data, c10::intrusive_ptr<c10d::ProcessGroup> process_group, c10::intrusive_ptr<c10d::ReduceOp> op) {
+void shm_allreduce(torch::Tensor& data, int64_t op) {
   RECORD_FUNCTION("sgl-kernel::shm_allreduce", std::vector<c10::IValue>({data}));
 
   TORCH_CHECK(op == c10d::ReduceOp::SUM, "Only torch.distributed.ReduceOp.SUM is supported");
 
   auto numel = data.numel();
-
-  int data_size = 0;
-  bool data_type_fallback = false;
-
-  switch (data.scalar_type()) {
-    case c10::ScalarType::BFloat16:
-      data_size = numel * 2;
-      break;
-    case c10::ScalarType::Float:
-      data_size = numel * 4;
-      break;
-    default:
-      data_type_fallback = true;
-  }
-
-  if (data_type_fallback || !all_ranks_local_p) {
-    // Fallback to torch distributed allreduce
-    std::vector<torch::Tensor> tensors = {data};
-    process_group->allreduce(tensors)->wait();
-  } else {
-    all_reduce_outer_loop(data, numel, data_size);
-  }
+  int data_size = numel * data.element_size();
+  all_reduce_outer_loop(data, numel, data_size);
 
   return;
 }
 
-torch::Tensor shm_allgather(torch::Tensor& data, c10::intrusive_ptr<c10d::ProcessGroup> process_group, int64_t dim) {
+torch::Tensor shm_allgather(torch::Tensor& data, int64_t dim) {
   RECORD_FUNCTION("sgl-kernel::shm_allgather", std::vector<c10::IValue>({data}));
 
   auto numel = data.numel();
-
-  int data_size = 0;
-  bool data_type_fallback = false;
-
-  switch (data.scalar_type()) {
-    case c10::ScalarType::BFloat16:
-      data_size = numel * 2;
-      break;
-    case c10::ScalarType::Float:
-      data_size = numel * 4;
-      break;
-    default:
-      data_type_fallback = true;
-  }
+  int data_size = numel * data.element_size();
   if (dim < 0) {
     dim += data.dim();
   }
-  if (data_type_fallback || !all_ranks_local_p) {
-    // Fallback to torch distributed allreduce
-    std::vector<std::vector<torch::Tensor>> output_tensors(1);
-    auto world_size = process_group->getSize();
-    for (int i = 0; i < world_size; i++) {
-      output_tensors[0].push_back(torch::empty_like(data));
-    }
-    std::vector<torch::Tensor> input_tensors = {data};
-    process_group->allgather(output_tensors, input_tensors)->wait();
-    return torch::cat(output_tensors[0], dim).contiguous();
-  }
   std::vector<int64_t> result_shape = data.sizes().vec();
   result_shape[dim] *= world_size;
   torch::Tensor result_tensor = torch::empty(result_shape, data.options());
diff --git a/sgl-kernel/csrc/cpu/torch_extension_cpu.cpp b/sgl-kernel/csrc/cpu/torch_extension_cpu.cpp
index 17e2f824c8f..4dc4f704f24 100644
--- a/sgl-kernel/csrc/cpu/torch_extension_cpu.cpp
+++ b/sgl-kernel/csrc/cpu/torch_extension_cpu.cpp
@@ -212,11 +212,10 @@ std::tuple<at::Tensor, at::Tensor, at::Tensor> qkv_proj_with_rope_fused_weight(
 void initialize(int64_t size, int64_t rank);
 
 // shared mmeory all_reduce
-void shm_allreduce(
-    at::Tensor& data, c10::intrusive_ptr<c10d::ProcessGroup> process_group, c10::intrusive_ptr<c10d::ReduceOp> op);
+void shm_allreduce(at::Tensor& data, int64_t op);
 
 // shared memory all_gather
-at::Tensor shm_allgather(at::Tensor& data, c10::intrusive_ptr<c10d::ProcessGroup> process_group, int64_t dim);
+at::Tensor shm_allgather(at::Tensor& data, int64_t dim);
 
 // rope
 std::tuple<at::Tensor, at::Tensor> rotary_embedding_cpu(
@@ -344,11 +343,9 @@ TORCH_LIBRARY_FRAGMENT(sgl_kernel, m) {
   // all reduce
   m.def("initialize(int size, int rank) -> ()");
   m.impl("initialize", torch::kCPU, &initialize);
-  m.def(
-      "shm_allreduce(Tensor data, __torch__.torch.classes.c10d.ProcessGroup process_group, "
-      "__torch__.torch.classes.c10d.ReduceOp reduce_op) -> ()");
+  m.def("shm_allreduce(Tensor data, int reduce_op) -> ()");
   m.impl("shm_allreduce", torch::kCPU, &shm_allreduce);
-  m.def("shm_allgather(Tensor data, __torch__.torch.classes.c10d.ProcessGroup process_group, int dim) -> Tensor");
+  m.def("shm_allgather(Tensor data, int dim) -> Tensor");
   m.impl("shm_allgather", torch::kCPU, &shm_allgather);
 
   // rope