diff --git a/dnn/src/common/algo_base.h b/dnn/src/common/algo_base.h
index 11724a96a87bfcf52322137f25df006aba929270..e0f3202bf1d65b63539cebb274619d5f39e7fe29 100644
--- a/dnn/src/common/algo_base.h
+++ b/dnn/src/common/algo_base.h
@@ -14,6 +14,7 @@
 
 #include <functional>
 #include <string>
+#include <tuple>
 
 #include "megdnn/oprs/base.h"
 #include "src/common/utils.h"
@@ -83,6 +84,29 @@ public:
     }
 };
 
+template <std::size_t I = 0, typename Opr, typename... Tp>
+inline typename std::enable_if<I == sizeof...(Tp), void>::type
+set_sub_execution_policy(const Opr*, std::tuple<Tp...>&) {}
+
+template <std::size_t I = 0, typename Opr, typename... Tp>
+        inline typename std::enable_if <
+        I<sizeof...(Tp), void>::type set_sub_execution_policy(
+                const Opr* opr, std::tuple<Tp...>& t) {
+    std::get<I>(t)->execution_policy() = opr->execution_policy().sub_policy[I];
+    set_sub_execution_policy<I + 1, Tp...>(opr, t);
+}
+
+template <typename Opr, typename... SubOpr>
+void set_execution_policy(const Opr* opr, SubOpr... sub_oprs) {
+    if (opr->execution_policy().algo.valid() &&
+        !opr->execution_policy().sub_policy.empty()) {
+        megdnn_assert(opr->execution_policy().sub_policy.size() ==
+                      sizeof...(sub_oprs));
+        auto&& sub = std::make_tuple(sub_oprs...);
+        set_sub_execution_policy<sizeof...(sub_oprs), Opr, SubOpr...>(opr, sub);
+    }
+}
+
 }  // namespace megdnn
 
 namespace std {
diff --git a/dnn/src/cuda/batched_matrix_mul/brute_force.cpp b/dnn/src/cuda/batched_matrix_mul/brute_force.cpp
index 62da5cc75aed977b00148cf3b5704fe56e762b33..96f03c20a09b4134bed584f9b1f3eed316377381 100644
--- a/dnn/src/cuda/batched_matrix_mul/brute_force.cpp
+++ b/dnn/src/cuda/batched_matrix_mul/brute_force.cpp
@@ -8,9 +8,12 @@
  * software distributed under the License is distributed on an
  * "AS IS" BASIS, WITHOUT ARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  */
+#include <algorithm>
+#include <memory>
 #include "./algo.h"
 #include "megdnn/opr_param_defs.h"
 #include "src/common/algo_chooser.h"
+#include "src/common/algo_base.h"
 #include "src/cuda/handle.h"
 #include "src/cuda/utils.h"
 
@@ -27,6 +30,20 @@ std::pair<TensorLayoutArray, MatrixMulForward::Param> sub_opr_config(
 
     return {{mm_layout_a, mm_layout_b, mm_layout_c}, opr->param()};
 }
+
+std::pair<TensorLayoutArray, std::unique_ptr<MatrixMulForward>> prepare_sub_opr(
+        const BatchedMatrixMulForwardImpl::AlgoBase::SizeArgs& args) {
+    auto matmul_opr = args.opr->handle()->create_operator<MatrixMulForward>();
+    set_execution_policy<BatchedMatrixMulForward, MatrixMulForward*>(
+            args.opr, matmul_opr.get());
+
+    auto&& config = sub_opr_config(args.layout_a, args.layout_b, args.layout_c,
+                                   args.opr);
+    matmul_opr->param() = config.second;
+
+    return {config.first, std::move(matmul_opr)};
+}
+
 }  // namespace
 
 std::vector<Algorithm::SearchItem>
@@ -43,51 +60,23 @@ BatchedMatrixMulForwardImpl::AlgoBruteForce::get_subopr_list(
 
 bool BatchedMatrixMulForwardImpl::AlgoBruteForce::is_available(
         const SizeArgs& args) const {
-    auto matmul_opr = args.opr->handle()->create_operator<MatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid() &&
-        !args.opr->execution_policy().sub_policy.empty()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        matmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
+    auto config = prepare_sub_opr(args);
 
-    auto&& config = sub_opr_config(args.layout_a, args.layout_b, args.layout_c,
-                                   args.opr);
-    matmul_opr->param() = config.second;
-
-    return get_algorithm(static_cast<MatrixMulForwardImpl*>(matmul_opr.get()),
-                         config.first[0], config.first[1], config.first[2]);
+    return get_algorithm(
+            static_cast<MatrixMulForwardImpl*>(config.second.get()),
+            config.first[0], config.first[1], config.first[2]);
 }
 size_t BatchedMatrixMulForwardImpl::AlgoBruteForce::get_workspace_in_bytes(
         const SizeArgs& args) const {
-    auto matmul_opr = args.opr->handle()->create_operator<MatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid() &&
-        !args.opr->execution_policy().sub_policy.empty()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        matmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config = sub_opr_config(args.layout_a, args.layout_b, args.layout_c,
-                                   args.opr);
-    matmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
-    return matmul_opr->get_workspace_in_bytes(config.first[0], config.first[1],
-                                              config.first[2]);
+    return config.second->get_workspace_in_bytes(
+            config.first[0], config.first[1], config.first[2]);
 }
 void BatchedMatrixMulForwardImpl::AlgoBruteForce::exec(
         const ExecArgs& args) const {
     auto N = args.layout_a.shape[0];
-    auto matmul_opr = args.opr->handle()->create_operator<MatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        matmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config = sub_opr_config(args.layout_a, args.layout_b, args.layout_c,
-                                   args.opr);
-    matmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     rep(n, N) {
         TensorND A_, B_, C_;
@@ -100,6 +89,6 @@ void BatchedMatrixMulForwardImpl::AlgoBruteForce::exec(
         tensor_n_from_batch(args.tensor_a, A_);
         tensor_n_from_batch(args.tensor_b, B_);
         tensor_n_from_batch(args.tensor_c, C_);
-        matmul_opr->exec(A_, B_, C_, args.workspace);
+        config.second->exec(A_, B_, C_, args.workspace);
     }
 }
diff --git a/dnn/src/cuda/conv_bias/batched_matmul.cpp b/dnn/src/cuda/conv_bias/batched_matmul.cpp
index 0bee59852ab0ff653092a544bb4e44aee2982cc1..543e88b8bee00ce11199255c0ec083ce14da5594 100644
--- a/dnn/src/cuda/conv_bias/batched_matmul.cpp
+++ b/dnn/src/cuda/conv_bias/batched_matmul.cpp
@@ -11,6 +11,7 @@
  */
 
 #include "src/common/algo_chooser.h"
+#include "src/common/algo_base.h"
 #include "src/common/conv_bias.h"
 #include "src/cuda/batched_matrix_mul/algo.h"
 #include "src/cuda/conv_bias/algo.h"
@@ -51,6 +52,19 @@ std::pair<TensorLayoutArray, MatrixMulForward::Param> sub_opr_config(
 
     return {{A, B, C}, param};
 }
+
+std::pair<TensorLayoutArray, std::unique_ptr<BatchedMatrixMulForward>>
+prepare_sub_opr(const ConvBiasForwardImpl::AlgoBase::SizeArgs& args) {
+    auto bmatmul_opr = args.handle->create_operator<BatchedMatrixMulForward>();
+    set_execution_policy<ConvBiasForward, BatchedMatrixMulForward*>(
+            args.opr, bmatmul_opr.get());
+    auto&& config =
+            sub_opr_config(args.filter_meta, *args.src_layout,
+                           *args.filter_layout, *args.dst_layout, args.opr);
+    bmatmul_opr->param() = config.second;
+
+    return {config.first, std::move(bmatmul_opr)};
+}
 }  // namespace
 
 std::vector<Algorithm::SearchItem>
@@ -74,18 +88,7 @@ bool ConvBiasForwardImpl::AlgoBatchedMatmul::is_available(
     if (args.z_layout->ndim > 0)
         return false;
 
-    auto bmatmul_opr = args.handle->create_operator<BatchedMatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid() &&
-        !args.opr->execution_policy().sub_policy.empty()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        bmatmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config =
-            sub_opr_config(args.filter_meta, *args.src_layout,
-                           *args.filter_layout, *args.dst_layout, args.opr);
-    bmatmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     auto&& fm = args.filter_meta;
     return fm.format == Param::Format::NCHW &&
@@ -95,9 +98,9 @@ bool ConvBiasForwardImpl::AlgoBatchedMatmul::is_available(
            fm.dilation[1] == 1 && fm.spatial[0] == 1 && fm.spatial[1] == 1 &&
            fm.padding[0] == 0 && fm.padding[1] == 0 && fm.stride[0] == 1 &&
            fm.stride[1] == 1 &&
-           get_algorithm(
-                   static_cast<BatchedMatrixMulForwardImpl*>(bmatmul_opr.get()),
-                   config.first[0], config.first[1], config.first[2]);
+           get_algorithm(static_cast<BatchedMatrixMulForwardImpl*>(
+                                 config.second.get()),
+                         config.first[0], config.first[1], config.first[2]);
 }
 
 WorkspaceBundle ConvBiasForwardImpl::AlgoBatchedMatmul::get_workspace_bundle(
@@ -115,21 +118,10 @@ WorkspaceBundle ConvBiasForwardImpl::AlgoBatchedMatmul::get_workspace_bundle(
     SizeArgs conv_args = args;
     conv_args.dst_layout = &dst_layout;
 
-    auto bmatmul_opr = args.handle->create_operator<BatchedMatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid() &&
-        !args.opr->execution_policy().sub_policy.empty()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        bmatmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config =
-            sub_opr_config(args.filter_meta, *args.src_layout,
-                           *args.filter_layout, *args.dst_layout, args.opr);
-    bmatmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     sizes.insert(sizes.begin(),
-                 args.handle->batched_matrix_mul()->get_workspace_in_bytes(
+                 config.second->get_workspace_in_bytes(
                          config.first[0], config.first[1], config.first[2]));
     return {ptr, std::move(sizes)};
 }
@@ -154,23 +146,12 @@ void ConvBiasForwardImpl::AlgoBatchedMatmul::exec(const ExecArgs& args) const {
     conv_args.dst_tensor = &conv_dst_tensor;
     conv_args.dst_layout = &conv_dst_tensor.layout;
     {
-        auto bmatmul_opr =
-                args.handle->create_operator<BatchedMatrixMulForward>();
-        if (args.opr->execution_policy().algo.valid()) {
-            megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-            bmatmul_opr->execution_policy() =
-                    args.opr->execution_policy().sub_policy[0];
-        }
-
-        auto&& config =
-                sub_opr_config(args.filter_meta, *args.src_layout,
-                               *args.filter_layout, *args.dst_layout, args.opr);
-        bmatmul_opr->param() = config.second;
+        auto config = prepare_sub_opr(args);
 
         TensorND A{args.filter_tensor->raw_ptr, config.first[0]},
                 B{args.src_tensor->raw_ptr, config.first[1]},
                 C{args.dst_tensor->raw_ptr, config.first[2]};
-        bmatmul_opr->exec(A, B, C, bundle.get_workspace(0));
+        config.second->exec(A, B, C, bundle.get_workspace(0));
     }
     handle_bias_and_nonlinear(args.handle, args.nonlinear_mode,
                               &conv_dst_tensor, args.dst_tensor,
diff --git a/dnn/src/cuda/conv_bias/bfloat16.cpp b/dnn/src/cuda/conv_bias/bfloat16.cpp
index 10c45434dab2426e96b4f13e8347300e9ba0383b..60567edbe1175d9f4dbfad8156c39698a852f3cb 100644
--- a/dnn/src/cuda/conv_bias/bfloat16.cpp
+++ b/dnn/src/cuda/conv_bias/bfloat16.cpp
@@ -14,6 +14,7 @@
 #include "src/cuda/handle.h"
 #include "src/cuda/utils.cuh"
 #include "src/cuda/utils.h"
+#include "src/common/algo_base.h"
 
 using namespace megdnn;
 using namespace cuda;
@@ -40,6 +41,18 @@ std::pair<TensorLayoutArray, ConvBiasForwardImpl::Param> sub_opr_config(
     ret.second.compute_mode = ConvBiasForwardImpl::Param::ComputeMode::DEFAULT;
     return ret;
 }
+
+std::pair<TensorLayoutArray, std::unique_ptr<ConvBiasForward>> prepare_sub_opr(
+        const ConvBiasForwardImpl::AlgoBase::SizeArgs& args) {
+    auto convbias_opr = args.handle->create_operator<ConvBias>();
+    auto&& config = sub_opr_config(
+            {*args.src_layout, *args.filter_layout, *args.bias_layout,
+             *args.z_layout, *args.dst_layout},
+            args.opr);
+    convbias_opr->param() = config.second;
+
+    return {config.first, std::move(convbias_opr)};
+}
 }  // namespace
 
 std::vector<Algorithm::SearchItem>
@@ -55,33 +68,18 @@ ConvBiasForwardImpl::AlgoBFloat16::get_subopr_list(
 
 bool ConvBiasForwardImpl::AlgoBFloat16::is_available(
         const SizeArgs& args) const {
-    auto convbias_opr = args.handle->create_operator<ConvBias>();
-    auto&& config = sub_opr_config(
-            {*args.src_layout, *args.filter_layout, *args.bias_layout,
-             *args.z_layout, *args.dst_layout},
-            args.opr);
-    convbias_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     return args.src_layout->dtype == args.filter_layout->dtype &&
            args.src_layout->dtype == dtype::BFloat16() &&
-           get_algorithm(static_cast<ConvBiasForwardImpl*>(convbias_opr.get()),
+           get_algorithm(static_cast<ConvBiasForwardImpl*>(config.second.get()),
                          config.first[0], config.first[1], config.first[2],
                          config.first[3], config.first[4]);
 }
 
 WorkspaceBundle ConvBiasForwardImpl::AlgoBFloat16::get_workspace_bundle(
         void* ptr, const SizeArgs& args) const {
-    auto convbias_opr = args.handle->create_operator<ConvBias>();
-    if (args.opr->execution_policy().algo.valid()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        convbias_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-    auto&& config = sub_opr_config(
-            {*args.src_layout, *args.filter_layout, *args.bias_layout,
-             *args.z_layout, *args.dst_layout},
-            args.opr);
-    convbias_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     SmallVector<size_t> sizes;
     auto get_workspace = [&sizes](const TensorLayout& src,
@@ -95,7 +93,7 @@ WorkspaceBundle ConvBiasForwardImpl::AlgoBFloat16::get_workspace_bundle(
     get_workspace(*args.bias_layout, config.first[2]);
     get_workspace(*args.z_layout, config.first[3]);
     get_workspace(*args.dst_layout, config.first[4]);
-    sizes.push_back(convbias_opr->get_workspace_in_bytes(
+    sizes.push_back(config.second->get_workspace_in_bytes(
             config.first[0], config.first[1], config.first[2], config.first[3],
             config.first[4], nullptr));
 
@@ -123,17 +121,10 @@ void ConvBiasForwardImpl::AlgoBFloat16::exec(const ExecArgs& args) const {
                 .src_to_comp_type(*args.dst_tensor, fdst_tensor);
     }
     {
-        auto convbias_opr = args.handle->create_operator<ConvBias>();
-        convbias_opr->param() = args.opr->param();
-        convbias_opr->param().compute_mode = Param::ComputeMode::DEFAULT;
-        if (args.opr->execution_policy().algo.valid()) {
-            megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-            convbias_opr->execution_policy() =
-                    args.opr->execution_policy().sub_policy[0];
-        }
+        auto config = prepare_sub_opr(args);
 
-        convbias_opr->exec(fsrc_tensor, ffilter_tensor, fbias_tensor, fz_tensor,
-                           fdst_tensor, nullptr, cvter.workspace());
+        config.second->exec(fsrc_tensor, ffilter_tensor, fbias_tensor,
+                            fz_tensor, fdst_tensor, nullptr, cvter.workspace());
     }
     { cvter.comp_to_dst_type(fdst_tensor, *args.dst_tensor); }
 }
diff --git a/dnn/src/cuda/conv_bias/matmul.cpp b/dnn/src/cuda/conv_bias/matmul.cpp
index 79f2e2fb160acfea5593bf90a4232d323d756ecb..709dc1131476d3b4c6ddb226e2d12f7972d2d79c 100644
--- a/dnn/src/cuda/conv_bias/matmul.cpp
+++ b/dnn/src/cuda/conv_bias/matmul.cpp
@@ -15,6 +15,7 @@
 #include "src/cuda/conv_bias/helper.h"
 #include "src/cuda/conv_bias/matmul/im2col.cuh"
 #include "src/cuda/utils.h"
+#include "src/common/algo_base.h"
 
 using namespace megdnn;
 using namespace cuda;
@@ -40,6 +41,19 @@ std::pair<TensorLayoutArray, MatrixMulForward::Param> sub_opr_config(
 
     return {{Al, Bl, Cl}, param};
 }
+
+std::pair<TensorLayoutArray, std::unique_ptr<MatrixMulForward>> prepare_sub_opr(
+        const ConvBiasForwardImpl::AlgoBase::SizeArgs& args) {
+    auto matmul_opr = args.handle->create_operator<MatrixMulForward>();
+    set_execution_policy<ConvBiasForward, MatrixMulForward*>(args.opr,
+                                                              matmul_opr.get());
+    auto&& config =
+            sub_opr_config(args.filter_meta, *args.src_layout,
+                           *args.filter_layout, *args.dst_layout, args.opr);
+    matmul_opr->param() = config.second;
+
+    return {config.first, std::move(matmul_opr)};
+}
 }  // namespace
 
 std::vector<Algorithm::SearchItem>
@@ -87,19 +101,8 @@ WorkspaceBundle ConvBiasForwardImpl::AlgoMatmul::get_workspace_bundle(
     conv_args.dst_layout = &dst_layout;
     SmallVector<size_t> matmul_sizes = matmul_get_workspace_bundle(conv_args);
 
-    auto matmul_opr = args.handle->create_operator<MatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid() &&
-        !args.opr->execution_policy().sub_policy.empty()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        matmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config =
-            sub_opr_config(args.filter_meta, *args.src_layout,
-                           *args.filter_layout, *args.dst_layout, args.opr);
-    matmul_opr->param() = config.second;
-    size_t mm_ws = matmul_opr->get_workspace_in_bytes(
+    auto config = prepare_sub_opr(args);
+    size_t mm_ws = config.second->get_workspace_in_bytes(
             config.first[0], config.first[1], config.first[2]);
     matmul_sizes.push_back(mm_ws);
 
@@ -162,17 +165,7 @@ void ConvBiasForwardImpl::AlgoMatmul::exec_internal(
                          args.src_layout->stride[0], IC, IH, IW, FH, FW, OH, OW,
                          PH, PW, SH, SW, DH, DW, stream);
 
-    auto matmul_opr = args.handle->create_operator<MatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        matmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config =
-            sub_opr_config(args.filter_meta, *args.src_layout,
-                           *args.filter_layout, *args.dst_layout, args.opr);
-    matmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     TensorND A(args.filter_tensor->ptr<T>(), config.first[0]),
             B(col, config.first[1]), C(dst_t, config.first[2]);
@@ -182,7 +175,7 @@ void ConvBiasForwardImpl::AlgoMatmul::exec_internal(
         matmul_ws_idx = 3;
     }
 
-    matmul_opr->exec(A, B, C, bundle.get_workspace(matmul_ws_idx));
+    config.second->exec(A, B, C, bundle.get_workspace(matmul_ws_idx));
 
     TensorLayout C2l({OC * OH * OW, N}, typename DTypeTrait<T>::dtype()),
             C3l = C2l;
diff --git a/dnn/src/cuda/convolution/backward_data/bfloat16.cpp b/dnn/src/cuda/convolution/backward_data/bfloat16.cpp
index 6e2e85b9c26307aa1f0c354fab64872ff9f13093..53830dbd27f405f59ab473c9b14fb3ddc1585ed9 100644
--- a/dnn/src/cuda/convolution/backward_data/bfloat16.cpp
+++ b/dnn/src/cuda/convolution/backward_data/bfloat16.cpp
@@ -10,6 +10,7 @@
  */
 
 #include "./algo.h"
+#include "src/common/algo_base.h"
 #include "src/cuda/convolution/chanwise/kern.cuh"
 #include "src/cuda/utils.h"
 
@@ -38,7 +39,19 @@ std::pair<TensorLayoutArray, ConvolutionBackwardDataImpl::Param> sub_opr_config(
             ConvolutionBackwardData::Param::ComputeMode::DEFAULT;
     return ret;
 }
+
+std::pair<TensorLayoutArray, std::unique_ptr<ConvolutionBackwardData>>
+prepare_sub_opr(const ConvolutionBackwardDataImpl::AlgoBase::SizeArgs& args) {
+    auto conv_back_data_opr =
+            args.handle->create_operator<ConvolutionBackwardData>();
+    auto&& config = sub_opr_config(
+            {*args.filter_layout, *args.diff_layout, *args.grad_layout},
+            args.opr);
+    conv_back_data_opr->param() = config.second;
+
+    return {config.first, std::move(conv_back_data_opr)};
 }
+}  // namespace
 
 std::vector<Algorithm::SearchItem>
 ConvolutionBackwardDataImpl::AlgoBFloat16::get_subopr_list(
@@ -54,33 +67,17 @@ ConvolutionBackwardDataImpl::AlgoBFloat16::get_subopr_list(
 
 bool ConvolutionBackwardDataImpl::AlgoBFloat16::is_available(
         const SizeArgs& args) const {
-    TensorLayout ffilter, fdiff, fgrad;
-    auto conv_back_data_opr =
-            args.handle->create_operator<ConvolutionBackwardData>();
-    auto&& config = sub_opr_config(
-            {*args.filter_layout, *args.diff_layout, *args.grad_layout},
-            args.opr);
-    conv_back_data_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
     return args.diff_layout->dtype == args.filter_layout->dtype &&
            args.diff_layout->dtype == dtype::BFloat16() &&
            get_algorithm(static_cast<ConvolutionBackwardDataImpl*>(
-                                 conv_back_data_opr.get()),
+                                 config.second.get()),
                          config.first[0], config.first[1], config.first[2]);
 }
 
 WorkspaceBundle ConvolutionBackwardDataImpl::AlgoBFloat16::get_workspace_bundle(
         void* ptr, const SizeArgs& args) const {
-    auto conv_back_data_opr =
-            args.handle->create_operator<ConvolutionBackwardData>();
-    if (args.opr->execution_policy().algo.valid()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        conv_back_data_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-    auto&& config = sub_opr_config(
-            {*args.filter_layout, *args.diff_layout, *args.grad_layout},
-            args.opr);
-    conv_back_data_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
     SmallVector<size_t> sizes;
     auto get_workspace = [&sizes](const TensorLayout& src,
                                   const TensorLayout& dst) {
@@ -92,7 +89,7 @@ WorkspaceBundle ConvolutionBackwardDataImpl::AlgoBFloat16::get_workspace_bundle(
     get_workspace(*args.diff_layout, config.first[1]);
     get_workspace(*args.grad_layout, config.first[2]);
 
-    sizes.push_back(conv_back_data_opr->get_workspace_in_bytes(
+    sizes.push_back(config.second->get_workspace_in_bytes(
             config.first[0], config.first[1], config.first[2]));
     return {ptr, std::move(sizes)};
 }
@@ -115,17 +112,9 @@ void ConvolutionBackwardDataImpl::AlgoBFloat16::exec(
                 .src_to_comp_type(*args.grad_tensor, fgrad_tensor);
     }
     {
-        auto conv_back_data_opr =
-                args.handle->create_operator<ConvolutionBackwardData>();
-        if (args.opr->execution_policy().algo.valid()) {
-            megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-            conv_back_data_opr->execution_policy() =
-                    args.opr->execution_policy().sub_policy[0];
-        }
-        conv_back_data_opr->param() = args.opr->param();
-        conv_back_data_opr->param().compute_mode = Param::ComputeMode::DEFAULT;
-        conv_back_data_opr->exec(ffilter_tensor, fdiff_tensor, fgrad_tensor,
-                                 cvter.workspace());
+        auto config = prepare_sub_opr(args);
+        config.second->exec(ffilter_tensor, fdiff_tensor, fgrad_tensor,
+                            cvter.workspace());
     }
     { cvter.comp_to_dst_type(fgrad_tensor, *args.grad_tensor); }
 }
diff --git a/dnn/src/cuda/convolution/backward_data/matmul.cpp b/dnn/src/cuda/convolution/backward_data/matmul.cpp
index d2cfea0adb276a17a2492b4a4aaaaa72ef23654e..e4059d4252c02756b9baa9c381d1a98546519b93 100644
--- a/dnn/src/cuda/convolution/backward_data/matmul.cpp
+++ b/dnn/src/cuda/convolution/backward_data/matmul.cpp
@@ -11,6 +11,7 @@
  */
 
 #include "./algo.h"
+#include "src/common/algo_base.h"
 #include "src/cuda/convolution/helper.h"
 #include "src/cuda/convolution/im2col.cuh"
 #include "src/cuda/matrix_mul/opr_impl.h"
@@ -43,6 +44,19 @@ std::pair<TensorLayoutArray, MatrixMulForward::Param> sub_opr_config(
     param.transposeA = true;
     return {{Al, Cl, Bl}, param};
 }
+
+std::pair<TensorLayoutArray, std::unique_ptr<MatrixMulForward>> prepare_sub_opr(
+        const ConvolutionBackwardDataImpl::AlgoBase::SizeArgs& args) {
+    auto matmul_opr = args.handle->create_operator<MatrixMulForward>();
+    set_execution_policy<ConvolutionBackwardData, MatrixMulForward*>(
+            args.opr, matmul_opr.get());
+    auto&& config =
+            sub_opr_config(args.filter_meta, *args.filter_layout,
+                           *args.diff_layout, *args.grad_layout, args.opr);
+    matmul_opr->param() = config.second;
+
+    return {config.first, std::move(matmul_opr)};
+}
 }  // namespace
 
 std::vector<Algorithm::SearchItem>
@@ -57,8 +71,7 @@ ConvolutionBackwardDataImpl::AlgoMatmul::get_subopr_list(
 
     std::string param_str;
     Algorithm::serialize_write_pod(config.second, param_str);
-    return {{Algorithm::OprType::MATRIX_MUL_FORWARD, param_str,
-             config.first}};
+    return {{Algorithm::OprType::MATRIX_MUL_FORWARD, param_str, config.first}};
 }
 
 bool ConvolutionBackwardDataImpl::AlgoMatmul::is_available(
@@ -75,22 +88,10 @@ bool ConvolutionBackwardDataImpl::AlgoMatmul::is_available(
 
 size_t ConvolutionBackwardDataImpl::AlgoMatmul::get_workspace_in_bytes(
         const SizeArgs& args) const {
-    auto matmul_opr =
-            args.handle->create_operator<MatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid() &&
-        !args.opr->execution_policy().sub_policy.empty()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        matmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config =
-            sub_opr_config(args.filter_meta, *args.filter_layout,
-                           *args.diff_layout, *args.grad_layout, args.opr);
-    matmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     auto&& sizes = matmul_get_workspace_bundle(args.as_fwd_args());
-    sizes.push_back(matmul_opr->get_workspace_in_bytes(
+    sizes.push_back(config.second->get_workspace_in_bytes(
             config.first[0], config.first[1], config.first[2]));
     return WorkspaceBundle(nullptr, sizes).total_size_in_bytes();
 }
@@ -121,19 +122,10 @@ void ConvolutionBackwardDataImpl::AlgoMatmul::exec_internal(
            DW = fm.dilation[1];
     auto stream = cuda_stream(args.handle);
 
-    auto matmul_opr = args.handle->create_operator<MatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        matmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-    auto&& config =
-            sub_opr_config(args.filter_meta, *args.filter_layout,
-                           *args.diff_layout, *args.grad_layout, args.opr);
-    matmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     auto&& sizes = matmul_get_workspace_bundle(args.as_fwd_args());
-    sizes.push_back(matmul_opr->get_workspace_in_bytes(
+    sizes.push_back(config.second->get_workspace_in_bytes(
             config.first[0], config.first[1], config.first[2]));
     auto wbundle = WorkspaceBundle(args.workspace.raw_ptr, sizes);
 
@@ -159,9 +151,9 @@ void ConvolutionBackwardDataImpl::AlgoMatmul::exec_internal(
         if (fm.should_flip) {
             convolution::flip_filter(args.as_fwd_args(),
                                      wbundle.get_workspace(2), A.raw_ptr);
-            matmul_opr->exec(A, C, B, wbundle.get_workspace(3));
+            config.second->exec(A, C, B, wbundle.get_workspace(3));
         } else {
-            matmul_opr->exec(A, C, B, wbundle.get_workspace(2));
+            config.second->exec(A, C, B, wbundle.get_workspace(2));
         }
     }
     {
diff --git a/dnn/src/cuda/convolution/backward_filter/bfloat16.cpp b/dnn/src/cuda/convolution/backward_filter/bfloat16.cpp
index 818987952e15f272f5374b67aeac5246d515df0c..bbd4ac1f10f105cef1693e4588a6c071a068293e 100644
--- a/dnn/src/cuda/convolution/backward_filter/bfloat16.cpp
+++ b/dnn/src/cuda/convolution/backward_filter/bfloat16.cpp
@@ -11,6 +11,7 @@
  */
 
 #include "./algo.h"
+#include "src/common/algo_base.h"
 #include "src/cuda/convolution/chanwise/kern.cuh"
 #include "src/cuda/utils.h"
 
@@ -39,6 +40,18 @@ sub_opr_config(const TensorLayoutArray& layouts,
             ConvolutionBackwardFilter::Param::ComputeMode::DEFAULT;
     return ret;
 }
+
+std::pair<TensorLayoutArray, std::unique_ptr<ConvolutionBackwardFilter>>
+prepare_sub_opr(const ConvolutionBackwardFilterImpl::AlgoBase::SizeArgs& args) {
+    auto conv_back_filter_opr =
+            args.handle->create_operator<ConvolutionBackwardFilter>();
+
+    auto&& config = sub_opr_config(
+            {*args.src_layout, *args.diff_layout, *args.grad_layout}, args.opr);
+    conv_back_filter_opr->param() = config.second;
+
+    return {config.first, std::move(conv_back_filter_opr)};
+}
 }  // namespace
 
 std::vector<Algorithm::SearchItem>
@@ -55,36 +68,18 @@ ConvolutionBackwardFilterImpl::AlgoBFloat16::get_subopr_list(
 
 bool ConvolutionBackwardFilterImpl::AlgoBFloat16::is_available(
         const SizeArgs& args) const {
-    TensorLayout fsrc, fdiff, fgrad;
-    auto conv_back_filter_opr =
-            args.handle->create_operator<ConvolutionBackwardFilter>();
-
-    auto&& config = sub_opr_config(
-            {*args.src_layout, *args.diff_layout, *args.grad_layout},
-            args.opr);
-    conv_back_filter_opr->param() =  config.second;
+    auto config = prepare_sub_opr(args);
     return args.src_layout->dtype == args.diff_layout->dtype &&
            args.src_layout->dtype == dtype::BFloat16() &&
            get_algorithm(static_cast<ConvolutionBackwardFilterImpl*>(
-                                 conv_back_filter_opr.get()),
+                                 config.second.get()),
                          config.first[0], config.first[1], config.first[2]);
 }
 
 WorkspaceBundle
 ConvolutionBackwardFilterImpl::AlgoBFloat16::get_workspace_bundle(
         void* ptr, const SizeArgs& args) const {
-    auto conv_back_filter_opr =
-            args.handle->create_operator<ConvolutionBackwardFilter>();
-    if (args.opr->execution_policy().algo.valid()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        conv_back_filter_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-    auto&& config = sub_opr_config(
-            {*args.src_layout, *args.diff_layout, *args.grad_layout},
-            args.opr);
-
-    conv_back_filter_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
     SmallVector<size_t> sizes;
     auto get_workspace = [&sizes](const TensorLayout& src,
                                   const TensorLayout& dst) {
@@ -96,7 +91,7 @@ ConvolutionBackwardFilterImpl::AlgoBFloat16::get_workspace_bundle(
     get_workspace(*args.src_layout, config.first[0]);
     get_workspace(*args.diff_layout, config.first[1]);
     get_workspace(*args.grad_layout, config.first[2]);
-    sizes.push_back(conv_back_filter_opr->get_workspace_in_bytes(
+    sizes.push_back(config.second->get_workspace_in_bytes(
             config.first[0], config.first[1], config.first[2]));
     auto ret = WorkspaceBundle{ptr, std::move(sizes)};
     return ret;
@@ -120,19 +115,9 @@ void ConvolutionBackwardFilterImpl::AlgoBFloat16::exec(
                 .src_to_comp_type(*args.grad_tensor, fgrad_tensor);
     }
     {
-        auto conv_back_filter_opr =
-                args.handle->create_operator<ConvolutionBackwardFilter>();
-        conv_back_filter_opr->param() = args.opr->param();
-        conv_back_filter_opr->param().compute_mode =
-                Param::ComputeMode::DEFAULT;
-
-        if (args.opr->execution_policy().algo.valid()) {
-            megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-            conv_back_filter_opr->execution_policy() =
-                    args.opr->execution_policy().sub_policy[0];
-        }
-        conv_back_filter_opr->exec(fsrc_tensor, fdiff_tensor, fgrad_tensor,
-                                   cvter.workspace());
+        auto config = prepare_sub_opr(args);
+        config.second->exec(fsrc_tensor, fdiff_tensor, fgrad_tensor,
+                            cvter.workspace());
     }
     { cvter.comp_to_dst_type(fgrad_tensor, *args.grad_tensor); }
 }
diff --git a/dnn/src/cuda/convolution/backward_filter/matmul.cpp b/dnn/src/cuda/convolution/backward_filter/matmul.cpp
index 5b2f3b64b2c93798a5e307ee902a3da5ad81171e..b5977e7d074e1d316890fd109dab04433d899660 100644
--- a/dnn/src/cuda/convolution/backward_filter/matmul.cpp
+++ b/dnn/src/cuda/convolution/backward_filter/matmul.cpp
@@ -11,6 +11,7 @@
  */
 
 #include "./algo.h"
+#include "src/common/algo_base.h"
 #include "src/cuda/convolution/helper.h"
 #include "src/cuda/convolution/im2col.cuh"
 #include "src/cuda/utils.h"
@@ -42,6 +43,20 @@ std::pair<TensorLayoutArray, MatrixMulForward::Param> sub_opr_config(
     param.transposeB = true;
     return {{Cl, Bl, Al}, param};
 }
+
+std::pair<TensorLayoutArray, std::unique_ptr<MatrixMulForward>> prepare_sub_opr(
+        const ConvolutionBackwardFilterImpl::AlgoBase::SizeArgs& args) {
+    auto matmul_opr = args.handle->create_operator<MatrixMulForward>();
+    set_execution_policy<ConvolutionBackwardFilter, MatrixMulForward*>(
+            args.opr, matmul_opr.get());
+
+    auto&& config =
+            sub_opr_config(args.grad_filter_meta, *args.src_layout,
+                           *args.diff_layout, *args.grad_layout, args.opr);
+    matmul_opr->param() = config.second;
+
+    return {config.first, std::move(matmul_opr)};
+}
 }  // namespace
 
 std::vector<Algorithm::SearchItem>
@@ -56,11 +71,9 @@ ConvolutionBackwardFilterImpl::AlgoMatmul::get_subopr_list(
 
     std::string param_str;
     Algorithm::serialize_write_pod(config.second, param_str);
-    return {{Algorithm::OprType::MATRIX_MUL_FORWARD, param_str,
-             config.first}};
+    return {{Algorithm::OprType::MATRIX_MUL_FORWARD, param_str, config.first}};
 }
 
-
 bool ConvolutionBackwardFilterImpl::AlgoMatmul::is_available(
         const SizeArgs& args) const {
     if (args.src_layout->dtype == args.diff_layout->dtype &&
@@ -75,21 +88,10 @@ bool ConvolutionBackwardFilterImpl::AlgoMatmul::is_available(
 
 size_t ConvolutionBackwardFilterImpl::AlgoMatmul::get_workspace_in_bytes(
         const SizeArgs& args) const {
-    auto matmul_opr = args.handle->create_operator<MatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid() &&
-        !args.opr->execution_policy().sub_policy.empty()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        matmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config =
-            sub_opr_config(args.grad_filter_meta, *args.src_layout,
-                           *args.diff_layout, *args.grad_layout, args.opr);
-    matmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     auto&& sizes = matmul_get_workspace_bundle(args.as_fwd_args());
-    sizes.push_back(matmul_opr->get_workspace_in_bytes(
+    sizes.push_back(config.second->get_workspace_in_bytes(
             config.first[0], config.first[1], config.first[2]));
     return WorkspaceBundle(nullptr, sizes).total_size_in_bytes();
 }
@@ -121,19 +123,10 @@ void ConvolutionBackwardFilterImpl::AlgoMatmul::exec_internal(
            DW = fm.dilation[1];
     auto stream = cuda_stream(args.handle);
 
-    auto matmul_opr = args.handle->create_operator<MatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        matmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-    auto&& config =
-            sub_opr_config(args.grad_filter_meta, *args.src_layout,
-                           *args.diff_layout, *args.grad_layout, args.opr);
-    matmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     auto&& sizes = matmul_get_workspace_bundle(args.as_fwd_args());
-    sizes.push_back(matmul_opr->get_workspace_in_bytes(
+    sizes.push_back(config.second->get_workspace_in_bytes(
             config.first[0], config.first[1], config.first[2]));
     auto wbundle = WorkspaceBundle(args.workspace.raw_ptr, sizes);
 
@@ -164,14 +157,14 @@ void ConvolutionBackwardFilterImpl::AlgoMatmul::exec_internal(
         TensorND A(args.grad_tensor->ptr<T>(), Al), B(col, Bl), C(diff_t, Cl);
         if (fm.should_flip) {
             A.raw_ptr = wbundle.get(2);
-            matmul_opr->exec(C, B, A, wbundle.get_workspace(3));
+            config.second->exec(C, B, A, wbundle.get_workspace(3));
             convolution::flip_filter(
                     args.as_fwd_args(),
                     {static_cast<dt_byte*>(args.grad_tensor->raw_ptr),
                      wbundle.get_size(2)},
                     A.raw_ptr);
         } else {
-            matmul_opr->exec(C, B, A, wbundle.get_workspace(2));
+            config.second->exec(C, B, A, wbundle.get_workspace(2));
         }
     }
 }
diff --git a/dnn/src/cuda/convolution/forward/algos.cpp b/dnn/src/cuda/convolution/forward/algos.cpp
index 3891bb7e13c04b2f986acd598b8fe2a03f23d7d6..161a8df1d27cbdc7198e37a96ccd9cf9e7c65843 100644
--- a/dnn/src/cuda/convolution/forward/algos.cpp
+++ b/dnn/src/cuda/convolution/forward/algos.cpp
@@ -65,6 +65,20 @@ std::pair<TensorLayoutArray, ConvBiasForward::Param> sub_opr_config(
     return ret;
 }
 
+std::pair<TensorLayoutArray, std::unique_ptr<ConvBiasForward>> prepare_sub_opr(
+        const ConvolutionForwardImpl::AlgoBase::SizeArgs& args) {
+    auto conv_bias_opr = args.opr->handle()->create_operator<ConvBiasForward>();
+    set_execution_policy<ConvolutionForward, ConvBiasForward*>(
+            args.opr, conv_bias_opr.get());
+
+    auto&& config = sub_opr_config(
+            *args.layout_src, *args.layout_filter, *args.layout_dst,
+            args.opr);
+    conv_bias_opr->param() = config.second;
+
+    return {config.first, std::move(conv_bias_opr)};
+}
+
 }  // namespace
 
 ConvolutionForwardImpl::AlgoPack::AlgoPack() {
@@ -121,13 +135,8 @@ ConvolutionForwardImpl::AlgoDefault::get_subopr_list(
 
 bool ConvolutionForwardImpl::AlgoDefault::is_available(
         const SizeArgs& args) const {
-    auto conv_bias_opr =
-            args.opr->handle()->create_operator<ConvBiasForward>();
-    auto&& config = sub_opr_config(
-            *args.layout_src, *args.layout_filter, *args.layout_dst,
-            args.opr);
-    conv_bias_opr->param() = config.second;
-    return get_algorithm(static_cast<ConvBiasForwardImpl*>(conv_bias_opr.get()),
+    auto config = prepare_sub_opr(args);
+    return get_algorithm(static_cast<ConvBiasForwardImpl*>(config.second.get()),
                          *args.layout_src, *args.layout_filter, config.first[0],
                          config.first[1], *args.layout_dst);
 }
@@ -135,36 +144,15 @@ bool ConvolutionForwardImpl::AlgoDefault::is_available(
 
 size_t ConvolutionForwardImpl::AlgoDefault::get_workspace_in_bytes(
         const SizeArgs& args) const {
-    auto conv_bias_opr = args.opr->handle()->create_operator<ConvBiasForward>();
-    if (args.opr->execution_policy().algo.valid() &&
-        !args.opr->execution_policy().sub_policy.empty()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        conv_bias_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config = sub_opr_config(
-            *args.layout_src, *args.layout_filter, *args.layout_dst,
-            args.opr);
-    conv_bias_opr->param() = config.second;
-    return conv_bias_opr->get_workspace_in_bytes(
+    auto config = prepare_sub_opr(args);
+    return config.second->get_workspace_in_bytes(
             *args.layout_src, *args.layout_filter, config.first[0],
             config.first[1], *args.layout_dst, nullptr);
 }
 
 void ConvolutionForwardImpl::AlgoDefault::exec(const ExecArgs& args) const {
-    auto conv_bias_opr = args.opr->handle()->create_operator<ConvBiasForward>();
-    if (args.opr->execution_policy().algo.valid()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        conv_bias_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config = sub_opr_config(
-            *args.layout_src, *args.layout_filter, *args.layout_dst,
-            args.opr);
-    conv_bias_opr->param() = config.second;
-    conv_bias_opr->exec(args.tensor_src, args.tensor_filter,
+    auto config = prepare_sub_opr(args);
+    config.second->exec(args.tensor_src, args.tensor_filter,
                         {nullptr, config.first[0]}, {nullptr, config.first[1]},
                         args.tensor_dst, nullptr, args.workspace);
 }
diff --git a/dnn/src/cuda/deformable_conv/bwd_data/algo_matmul.cpp b/dnn/src/cuda/deformable_conv/bwd_data/algo_matmul.cpp
index e1befc39551a6d5d92fb951e26e45863a1dc2bdf..32579cd989754559550f57b977d5bb309792a1d3 100644
--- a/dnn/src/cuda/deformable_conv/bwd_data/algo_matmul.cpp
+++ b/dnn/src/cuda/deformable_conv/bwd_data/algo_matmul.cpp
@@ -14,6 +14,7 @@
 #include "src/cuda/deformable_conv/bwd_data/algo.h"
 #include "src/cuda/deformable_conv/kimpl/deformable_conv.cuh"
 #include "src/cuda/deformable_conv/opr_impl.h"
+#include "src/common/algo_base.h"
 
 using namespace megdnn;
 using namespace cuda;
@@ -79,15 +80,28 @@ std::pair<TensorLayoutArray, BatchedMatrixMulForward::Param> sub_opr_config(
     return {{al, bl, cl}, param};
 }
 
+std::pair<TensorLayoutArray, std::unique_ptr<BatchedMatrixMulForward>>
+prepare_sub_opr(
+        const DeformableConvBackwardDataImpl::AlgoBase::SizeArgs& args) {
+    auto bmatmul_opr = args.handle->create_operator<BatchedMatrixMulForward>();
+    set_execution_policy<DeformableConvBackwardData, BatchedMatrixMulForward*>(
+            args.opr, bmatmul_opr.get());
+
+    auto&& config = sub_opr_config(args.filter_meta, args.im_layout,
+                                   args.out_grad_layout);
+    bmatmul_opr->param() = config.second;
+
+    return {config.first, std::move(bmatmul_opr)};
+}
+
 };  // anonymous namespace
 
-std::vector<Algorithm::SearchItem>
-Algo::get_subopr_list(
+std::vector<Algorithm::SearchItem> Algo::get_subopr_list(
         const TensorLayoutArray& layouts, const OperatorBase* opr) const {
     const DeformableConvBackwardDataImpl* deformable_conv =
             static_cast<const DeformableConvBackwardDataImpl*>(opr);
     CanonizedFilterMeta fm = deformable_conv->make_canonized_filter_meta(
-        layouts[0].ndim, layouts[1], layouts[2]);
+            layouts[0].ndim, layouts[1], layouts[2]);
     auto&& config = sub_opr_config(fm, layouts[0], layouts[4]);
 
     std::string param_str;
@@ -106,19 +120,9 @@ WorkspaceBundle Algo::get_bundle(const SizeArgs& args) {
            OC = args.out_grad_layout[1], OH = args.out_grad_layout[2],
            OW = args.out_grad_layout[3], FH = fm.spatial[0], FW = fm.spatial[1];
 
-    auto bmatmul_opr = args.handle->create_operator<BatchedMatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid() &&
-        !args.opr->execution_policy().sub_policy.empty()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        bmatmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config = sub_opr_config(args.filter_meta, args.im_layout,
-                                   args.out_grad_layout);
-    bmatmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
-    size_t bmm_ws = bmatmul_opr->get_workspace_in_bytes(
+    size_t bmm_ws = config.second->get_workspace_in_bytes(
             config.first[0], config.first[1], config.first[2]);
     size_t result_ws = batch_sz * IC * FH * FW * OH * OW * sizeof(float);
     size_t relayout_ws1 = batch_sz * OC * OH * OW * sizeof(float);
@@ -183,24 +187,14 @@ void Algo::exec(const ExecArgs& args) const {
     // matmul [g, icpg, FH, FW, ocpg] * [g, ocpg, N, OH, OW] =>
     //        => [g, icpg, FH, FW, N, OH, OW]
     {
-        auto bmatmul_opr =
-                args.handle->create_operator<BatchedMatrixMulForward>();
-        if (args.opr->execution_policy().algo.valid()) {
-            megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-            bmatmul_opr->execution_policy() =
-                    args.opr->execution_policy().sub_policy[0];
-        }
-
-        auto&& config = sub_opr_config(args.filter_meta, args.im_layout,
-                                       args.out_grad_layout);
-        bmatmul_opr->param() = config.second;
+        auto config = prepare_sub_opr(args);
 
         TensorND A(static_cast<void*>(dev_filter), config.first[0]),
                 B(static_cast<void*>(relayout_ws1), config.first[1]),
                 C(static_cast<void*>(result_ws), config.first[2]);
 
         size_t bmm_ws_size = bundle.get_size(0);
-        bmatmul_opr->exec(
+        config.second->exec(
                 A, B, C,
                 Workspace(static_cast<megdnn::dt_byte*>(bmm_ws), bmm_ws_size));
     }
diff --git a/dnn/src/cuda/deformable_conv/bwd_flt/algo_matmul.cpp b/dnn/src/cuda/deformable_conv/bwd_flt/algo_matmul.cpp
index e011ebcc57c0247b1eafd8ecd6895f4d4f4d6999..7d8d303562be163b1f87922e36c2c4f9b0714a9e 100644
--- a/dnn/src/cuda/deformable_conv/bwd_flt/algo_matmul.cpp
+++ b/dnn/src/cuda/deformable_conv/bwd_flt/algo_matmul.cpp
@@ -15,6 +15,7 @@
 #include "src/cuda/deformable_conv/bwd_flt/algo.h"
 #include "src/cuda/deformable_conv/kimpl/deformable_conv.cuh"
 #include "src/cuda/deformable_conv/opr_impl.h"
+#include "src/common/algo_base.h"
 
 using namespace megdnn;
 using namespace cuda;
@@ -79,10 +80,23 @@ std::pair<TensorLayoutArray, BatchedMatrixMulForward::Param> sub_opr_config(
     return {{al, bl, cl}, param};
 }
 
+std::pair<TensorLayoutArray, std::unique_ptr<BatchedMatrixMulForward>>
+prepare_sub_opr(
+        const DeformableConvBackwardFilterImpl::AlgoBase::SizeArgs& args) {
+    auto bmatmul_opr = args.handle->create_operator<BatchedMatrixMulForward>();
+    set_execution_policy<DeformableConvBackwardFilter,
+                         BatchedMatrixMulForward*>(args.opr, bmatmul_opr.get());
+
+    auto&& config = sub_opr_config(args.filter_grad_meta, args.im_layout,
+                                   args.out_grad_layout);
+    bmatmul_opr->param() = config.second;
+
+    return {config.first, std::move(bmatmul_opr)};
+}
+
 };  // anonymous namespace
 
-std::vector<Algorithm::SearchItem>
-Algo::get_subopr_list(
+std::vector<Algorithm::SearchItem> Algo::get_subopr_list(
         const TensorLayoutArray& layouts, const OperatorBase* opr) const {
     const DeformableConvBackwardFilterImpl* deformable_conv =
             static_cast<const DeformableConvBackwardFilterImpl*>(opr);
@@ -107,21 +121,11 @@ WorkspaceBundle Algo::get_bundle(const SizeArgs& args) {
     size_t IC = fm.group * fm.icpg, OC = args.out_grad_layout[1];
     auto batch_sz = args.im_layout[0];
 
-    auto bmatmul_opr = args.handle->create_operator<BatchedMatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid() &&
-        !args.opr->execution_policy().sub_policy.empty()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        bmatmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config = sub_opr_config(args.filter_grad_meta, args.im_layout,
-                                   args.out_grad_layout);
-    bmatmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     size_t col_ws = batch_sz * IC * FH * FW * OH * OW * sizeof(float);
     size_t out_grad_ws = batch_sz * OC * OH * OW * sizeof(float);
-    size_t bmm_ws = bmatmul_opr->get_workspace_in_bytes(
+    size_t bmm_ws = config.second->get_workspace_in_bytes(
             config.first[0], config.first[1], config.first[2]);
 
     return {nullptr, {col_ws, out_grad_ws, bmm_ws}};
@@ -166,23 +170,14 @@ void Algo::exec(const ExecArgs& args) const {
 
     args.handle->relayout_opr()->exec(C2, C3);
     // matmul
-    auto bmatmul_opr = args.handle->create_operator<BatchedMatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        bmatmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config = sub_opr_config(args.filter_grad_meta, args.im_layout,
-                                   args.out_grad_layout);
-    bmatmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     TensorND A(static_cast<void*>(out_grad_ws), config.first[0]),
             B(static_cast<void*>(col_ws), config.first[1]),
             C(static_cast<void*>(dev_filter_grad), config.first[2]);
 
     size_t bmm_ws_size = bundle.get_size(2);
-    bmatmul_opr->exec(
+    config.second->exec(
             A, B, C,
             Workspace(static_cast<megdnn::dt_byte*>(bmm_ws), bmm_ws_size));
 }
diff --git a/dnn/src/cuda/deformable_conv/fwd/algo_matmul.cpp b/dnn/src/cuda/deformable_conv/fwd/algo_matmul.cpp
index d59fdb300b066ba30b5f062371500e7dabdb3c89..ce32a28f2481e54a3cce99d5cf0413c45b52eb56 100644
--- a/dnn/src/cuda/deformable_conv/fwd/algo_matmul.cpp
+++ b/dnn/src/cuda/deformable_conv/fwd/algo_matmul.cpp
@@ -14,6 +14,7 @@
 #include "src/cuda/batched_matrix_mul/algo.h"
 #include "src/cuda/deformable_conv/fwd/algo.h"
 #include "src/cuda/deformable_conv/kimpl/deformable_conv.cuh"
+#include "src/common/algo_base.h"
 
 using namespace megdnn;
 using namespace cuda;
@@ -78,15 +79,27 @@ std::pair<TensorLayoutArray, BatchedMatrixMulForward::Param> sub_opr_config(
     return {{al, bl, cl}, param};
 }
 
+std::pair<TensorLayoutArray, std::unique_ptr<BatchedMatrixMulForward>>
+prepare_sub_opr(const DeformableConvForwardImpl::AlgoBase::SizeArgs& args) {
+    auto bmatmul_opr = args.handle->create_operator<BatchedMatrixMulForward>();
+    set_execution_policy<DeformableConvForward, BatchedMatrixMulForward*>(
+            args.opr, bmatmul_opr.get());
+
+    auto&& config =
+            sub_opr_config(args.filter_meta, args.im_layout, args.dst_layout);
+    bmatmul_opr->param() = config.second;
+
+    return {config.first, std::move(bmatmul_opr)};
+}
+
 };  // anonymous namespace
 
-std::vector<Algorithm::SearchItem>
-Algo::get_subopr_list(
+std::vector<Algorithm::SearchItem> Algo::get_subopr_list(
         const TensorLayoutArray& layouts, const OperatorBase* opr) const {
     const DeformableConvForwardImpl* deformable_conv =
             static_cast<const DeformableConvForwardImpl*>(opr);
     CanonizedFilterMeta fm = deformable_conv->make_canonized_filter_meta(
-        layouts[0].ndim, layouts[1], layouts[2]);
+            layouts[0].ndim, layouts[1], layouts[2]);
     auto&& config = sub_opr_config(fm, layouts[0], layouts[4]);
 
     std::string param_str;
@@ -95,7 +108,6 @@ Algo::get_subopr_list(
              config.first}};
 }
 
-
 bool Algo::is_available(const SizeArgs&) const {
     return true;
 }
@@ -106,20 +118,10 @@ WorkspaceBundle Algo::get_bundle(const SizeArgs& args) {
            OC = args.dst_layout[1], OH = args.dst_layout[2],
            OW = args.dst_layout[3], FH = fm.spatial[0], FW = fm.spatial[1];
 
-    auto bmatmul_opr = args.handle->create_operator<BatchedMatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid() &&
-        !args.opr->execution_policy().sub_policy.empty()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        bmatmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config =
-            sub_opr_config(args.filter_meta, args.im_layout, args.dst_layout);
-    bmatmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     size_t col_ws = batch_sz * IC * FH * FW * OH * OW * sizeof(float);
-    size_t bmm_ws = bmatmul_opr->get_workspace_in_bytes(
+    size_t bmm_ws = config.second->get_workspace_in_bytes(
             config.first[0], config.first[1], config.first[2]);
     size_t result_ws = batch_sz * OC * OH * OW * sizeof(float);
 
@@ -154,16 +156,7 @@ void Algo::exec(const ExecArgs& args) const {
     deformable_conv::im2col(dev_im, dev_offset, dev_mask,
                             static_cast<float*>(col_ws), p);
 
-    auto bmatmul_opr = args.handle->create_operator<BatchedMatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        bmatmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-
-    auto&& config =
-            sub_opr_config(args.filter_meta, args.im_layout, args.dst_layout);
-    bmatmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     // matmul
     TensorND A(static_cast<void*>(dev_filter), config.first[0]),
@@ -171,7 +164,7 @@ void Algo::exec(const ExecArgs& args) const {
             C(static_cast<void*>(result_ws), config.first[2]);
 
     size_t bmm_ws_size = bundle.get_size(1);
-    bmatmul_opr->exec(
+    config.second->exec(
             A, B, C,
             Workspace(static_cast<megdnn::dt_byte*>(bmm_ws), bmm_ws_size));
     // relayout
diff --git a/dnn/src/cuda/matrix_mul/bfloat16.cpp b/dnn/src/cuda/matrix_mul/bfloat16.cpp
index 8c165e293f96f40d0574748ddd59d6e5d5c7ef18..329112ea1e64d4e0f603c92e4727082e5dd5f70a 100644
--- a/dnn/src/cuda/matrix_mul/bfloat16.cpp
+++ b/dnn/src/cuda/matrix_mul/bfloat16.cpp
@@ -14,6 +14,7 @@
 #include "src/cuda/matrix_mul/algos.h"
 #include "src/cuda/utils.h"
 #include "src/common/algo_chooser.h"
+#include "src/common/algo_base.h"
 
 using namespace megdnn;
 using namespace cuda;
@@ -37,6 +38,15 @@ std::pair<TensorLayoutArray, MatrixMulForwardImpl::Param> sub_opr_config(
     ret.second.compute_mode = MatrixMulForwardImpl::Param::ComputeMode::DEFAULT;
     return ret;
 }
+
+std::pair<TensorLayoutArray, std::unique_ptr<MatrixMulForward>> prepare_sub_opr(
+        const MatrixMulForwardImpl::AlgoBase::SizeArgs& args) {
+    auto&& config = sub_opr_config(
+            {args.layout_a, args.layout_b, args.layout_c}, args.opr);
+    auto matmul_opr = args.opr->handle()->create_operator<MatrixMulForward>();
+    matmul_opr->param() = config.second;
+    return {config.first, std::move(matmul_opr)};
+}
 }  // namespace
 
 std::vector<Algorithm::SearchItem>
@@ -52,27 +62,16 @@ MatrixMulForwardImpl::AlgoBFloat16::get_subopr_list(
 
 bool MatrixMulForwardImpl::AlgoBFloat16::is_available(
         const SizeArgs& args) const {
-    auto&& config = sub_opr_config(
-            {args.layout_a, args.layout_b, args.layout_c}, args.opr);
-    auto matmul_opr = args.opr->handle()->create_operator<MatrixMulForward>();
-    matmul_opr->param() = config.second;
-
+    auto config = prepare_sub_opr(args);
     return args.layout_a.dtype == dtype::BFloat16() &&
-           get_algorithm(static_cast<MatrixMulForwardImpl*>(matmul_opr.get()),
-                         config.first[0], config.first[1], config.first[2]);
+           get_algorithm(
+                   static_cast<MatrixMulForwardImpl*>(config.second.get()),
+                   config.first[0], config.first[1], config.first[2]);
 }
 
 WorkspaceBundle MatrixMulForwardImpl::AlgoBFloat16::get_workspace_bundle(
         void* ptr, const SizeArgs& args) const {
-    auto matmul_opr = args.opr->handle()->create_operator<MatrixMulForward>();
-    if (args.opr->execution_policy().algo.valid()) {
-        megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-        matmul_opr->execution_policy() =
-                args.opr->execution_policy().sub_policy[0];
-    }
-    auto&& config = sub_opr_config(
-            {args.layout_a, args.layout_b, args.layout_c}, args.opr);
-    matmul_opr->param() = config.second;
+    auto config = prepare_sub_opr(args);
 
     SmallVector<size_t> sizes;
     auto get_workspace = [&sizes](const TensorLayout& src,
@@ -85,7 +84,7 @@ WorkspaceBundle MatrixMulForwardImpl::AlgoBFloat16::get_workspace_bundle(
     get_workspace(args.layout_a, config.first[0]);
     get_workspace(args.layout_b, config.first[1]);
     get_workspace(args.layout_c, config.first[2]);
-    sizes.push_back(matmul_opr->get_workspace_in_bytes(
+    sizes.push_back(config.second->get_workspace_in_bytes(
             config.first[0], config.first[1], config.first[2]));
     return {ptr, std::move(sizes)};
 }
@@ -106,17 +105,8 @@ void MatrixMulForwardImpl::AlgoBFloat16::exec(const ExecArgs& args) const {
             .src_to_comp_type(args.tensor_b, b)
             .src_to_comp_type(args.tensor_c, c);
     {
-        auto matmul_opr =
-                args.opr->handle()->create_operator<MatrixMulForward>();
-        matmul_opr->param() = args.opr->param();
-        matmul_opr->param().compute_mode = Param::ComputeMode::DEFAULT;
-        if (args.opr->execution_policy().algo.valid()) {
-            megdnn_assert(args.opr->execution_policy().sub_policy.size() == 1);
-            matmul_opr->execution_policy() =
-                    args.opr->execution_policy().sub_policy[0];
-        }
-
-        matmul_opr->exec(a, b, c, ctypecvt.workspace());
+        auto config = prepare_sub_opr(args);
+        config.second->exec(a, b, c, ctypecvt.workspace());
     }
     ctypecvt.comp_to_dst_type(c, args.tensor_c);
 }