diff --git a/lite/kernels/arm/conv_winograd.cc b/lite/kernels/arm/conv_winograd.cc
index 90fe63662bd4ff7ea147707ae2e91ffbaff4478d..e433a3f4bb4a7aa553fbb1193ff82779d9af3242 100644
--- a/lite/kernels/arm/conv_winograd.cc
+++ b/lite/kernels/arm/conv_winograd.cc
@@ -35,7 +35,8 @@ void WinogradConv<PRECISION(kFloat), PRECISION(kFloat)>::ReInitWhenNeeded() {
   if (last_shape_ == x_dims) {
     return;
   }
-
+  last_shape_ = x_dims;
+  //! update workspace size
   int ic = x_dims[1];
   int ih = x_dims[2];
   int iw = x_dims[3];
@@ -43,6 +44,20 @@ void WinogradConv<PRECISION(kFloat), PRECISION(kFloat)>::ReInitWhenNeeded() {
   int oh = o_dims[2];
   int ow = o_dims[3];
   int tile_block = 8;
+  auto pad = *(param.paddings);
+  int pad_h = pad[0];
+  int pad_w = pad[2];
+  int oc_pad = (oc + 3) / 4 * 4;
+  int ic_pad = (ic + 3) / 4 * 4;
+  const int new_input_size =
+      (ic + 3) / 4 * 4 * (ih + pad_h * 2) * (iw + pad_w * 2);
+  const int temp_size =
+      (tile_block * ((ic + 3) / 4 + (oc + 3) / 4) * 4 * wino_iw * wino_iw +
+       8 * wino_iw * wino_iw) *
+      threads;
+  workspace_size_ = (temp_size + new_input_size) * sizeof(float);
+
+  //! update trans weights impl
   choose_small_ = ow * oh / (tile_block * threads) < 36 ? true : false;
   if (choose_small_) {
     wino_iw = 4;
@@ -58,18 +73,7 @@ void WinogradConv<PRECISION(kFloat), PRECISION(kFloat)>::ReInitWhenNeeded() {
     }
     last_function_ = 1;
   }
-  auto pad = *(param.paddings);
-  int pad_h = pad[0];
-  int pad_w = pad[2];
-  int oc_pad = (oc + 3) / 4 * 4;
-  int ic_pad = (ic + 3) / 4 * 4;
-  const int new_input_size =
-      (ic + 3) / 4 * 4 * (ih + pad_h * 2) * (iw + pad_w * 2);
-  const int temp_size =
-      (tile_block * ((ic + 3) / 4 + (oc + 3) / 4) * 4 * wino_iw * wino_iw +
-       8 * wino_iw * wino_iw) *
-      threads;
-  workspace_size_ = (temp_size + new_input_size) * sizeof(float);
+
   weights_.Resize({1, 1, 1, wino_iw * wino_iw * oc_pad * ic_pad});
   void* trans_tmp_ptr = malloc(sizeof(float) * wino_iw * wino_iw * oc * ic);
   auto weights_data_ = weights_.mutable_data<float>();
@@ -81,8 +85,6 @@ void WinogradConv<PRECISION(kFloat), PRECISION(kFloat)>::ReInitWhenNeeded() {
         weights_data_, param.filter->data<float>(), ic, oc, trans_tmp_ptr);
   }
   free(trans_tmp_ptr);
-
-  last_shape_ = x_dims;
 }
 
 template <>