rm singleton

ppcls/arch/backbone/legendary_models/swin_transformer.py

@@ -73,25 +73,12 @@ def get_roll_index(H, W, shifts, place):
     return [index_fp, index_bp]
 
 
-def singleton(cls):
-    def wrapper_singleton(*args, **kwargs):
-        if not wrapper_singleton.instance:
-            wrapper_singleton.instance = cls(*args, **kwargs)
-        return wrapper_singleton.instance
-    wrapper_singleton.instance = None
-    return wrapper_singleton
-
-@singleton
-class RollWrapperSingleton():
+class NpuRollWithIndexSelect():
     def __init__(self):
         self.index_dict = {}
         self.roll_with_index_select = RollWithIndexSelect.apply
-        self.enable = True if 'npu' in paddle.device.get_all_custom_device_type() else False
 
     def __call__(self, x, shifts, axis):
-        if not self.enable:
-            return paddle.roll(x, shifts, axis)
-
         assert x.dim() == 4
         assert len(shifts) == 2
         assert len(axis) == 2
@@ -103,6 +90,18 @@ class RollWrapperSingleton():
         return self.roll_with_index_select(x, index_fp, index_bp)
 
 
+class RollWrapper(object):
+
+    _roll = None
+
+    @staticmethod
+    def roll(x, shifts, axis):
+        if RollWrapper._roll is None:
+            RollWrapper._roll = NpuRollWithIndexSelect() if 'npu' in paddle.device.get_all_custom_device_type() else paddle.roll
+
+        return RollWrapper._roll(x, shifts, axis)
+
+
 class Mlp(nn.Layer):
     def __init__(self,
                  in_features,
@@ -414,10 +413,9 @@ class SwinTransformerBlock(nn.Layer):
         x = self.norm1(x)
         x = x.reshape([B, H, W, C])
 
-        roll = RollWrapperSingleton()
         # cyclic shift
         if self.shift_size > 0:
-            shifted_x = roll(
+            shifted_x = RollWrapper.roll(
                 x, shifts=(-self.shift_size, -self.shift_size), axis=(1, 2))
         else:
             shifted_x = x
@@ -441,7 +439,7 @@ class SwinTransformerBlock(nn.Layer):
 
         # reverse cyclic shift
         if self.shift_size > 0:
-            x = roll(
+            x = RollWrapper.roll(
                 shifted_x,
                 shifts=(self.shift_size, self.shift_size),
                 axis=(1, 2))