add dropout primtive

mindspore/nn/layer/basic.py

@@ -25,6 +25,7 @@ from mindspore.ops.operations import _inner_ops as inner
 from mindspore.common.parameter import Parameter
 from mindspore._extends import cell_attr_register
 from mindspore.common.api import ms_function
+from mindspore import context
 from ..cell import Cell
 from .activation import get_activation
 from ..._checkparam import Validator as validator
@@ -84,8 +85,19 @@ class Dropout(Cell):
         self.dropout_gen_mask = P.DropoutGenMask(Seed0=seed0, Seed1=seed1)
         self.dropout_do_mask = P.DropoutDoMask()
         self.cast = P.Cast()
+        self.is_gpu = context.get_context('device_target') in ["GPU"]
+
+        if self.is_gpu:
+            self.dropout = P.Dropout(keep_prob)
 
     def construct(self, x):
+        if not self.training:
+            return x
+
+        if self.is_gpu:
+            out, _ = self.dropout(x)
+            return out
+
         shape = self.get_shape(x)
         dtype = P.DType()(x)
         keep_prob = self.cast(self.keep_prob, dtype)

mindspore/ops/_grad/grad_nn_ops.py

@@ -643,3 +643,17 @@ def get_bprop_binary_cross_entropy(self):
         return dx, zeros_like(y), zeros_like(weight)
 
     return bprop
+
+
+@bprop_getters.register(P.Dropout)
+def get_bprop_dropout(self):
+    """Grad definition for `Dropout` operation."""
+    grad = P.DropoutGrad(self.drop_prob)
+
+    def bprop(x, out, dout):
+        _, mask = out
+        dy, _ = dout
+        dx = grad(dy, mask)
+        return (dx,)
+
+    return bprop

mindspore/ops/operations/__init__.py

@@ -52,7 +52,7 @@ from .random_ops import (RandomChoiceWithMask)
 from .nn_ops import (LSTM, SGD, Adam, ApplyMomentum, BatchNorm,
                      BiasAdd, Conv2D,
                      DepthwiseConv2dNative,
-                     DropoutDoMask,
+                     DropoutDoMask, DropoutGrad, Dropout,
                      DropoutGenMask, Flatten, FusedBatchNorm,
                      Gelu, Elu,
                      GetNext, L2Normalize, LayerNorm, L2Loss,
@@ -157,6 +157,8 @@ __all__ = [
     'Shape',
     'DropoutDoMask',
     'DropoutGenMask',
+    'DropoutGrad',
+    'Dropout',
     'Neg',
     'Slice',
     'DType',

mindspore/ops/operations/nn_ops.py

@@ -2762,3 +2762,68 @@ class ConfusionMulGrad(PrimitiveWithInfer):
         validator.check_subclass("input1_dtype", input1_dtype, mstype.tensor, self.name)
         validator.check_subclass("input2_dtype", input2_dtype, mstype.tensor, self.name)
         return input0_dtype, input1_dtype
+
+
+class Dropout(PrimitiveWithInfer):
+    """
+    During training, randomly zeroes some of the elements of the input tensor with probability.
+
+    Args:
+        drop_prob (float): probability of an element to be zeroed. Default: 0.
+
+    Inputs:
+        - **shape** (tuple[int]) - The shape of target mask.
+
+    Outputs:
+        Tensor, the value of generated mask for input shape.
+
+    Examples:
+        >>> dropout = P.Dropout(drop_prob=0.5)
+        >>> in = Tensor((20, 16, 50, 50))
+        >>> out = dropout(in)
+    """
+    @prim_attr_register
+    def __init__(self, drop_prob=0):
+        self.drop_prob = validator.check_number_range("drop_prob", drop_prob, 0, 1, Rel.INC_BOTH, self.name)
+
+    def infer_shape(self, x_shape):
+        validator.check_integer("x_shape", len(x_shape), 1, Rel.GE, self.name)
+        mask_shape = x_shape
+        return x_shape, mask_shape
+
+    def infer_dtype(self, x_dtype):
+        valid_types = (mstype.float16, mstype.float32)
+        validator.check_tensor_type_same({"x_dtype": x_dtype}, valid_types, self.name)
+        return x_dtype, x_dtype
+
+
+class DropoutGrad(PrimitiveWithInfer):
+    """
+    The gradient of Dropout. During training, randomly zeroes some of the elements
+    of the input tensor with probability.
+
+    Args:
+        drop_prob (float): probability of an element to be zeroed. Default: 0.
+
+    Inputs:
+        - **shape** (tuple[int]) - The shape of target mask.
+
+    Outputs:
+        Tensor, the value of generated mask for input shape.
+
+    Examples:
+        >>> dropout_grad = P.DropoutGrad(drop_prob=0.5)
+        >>> in = Tensor((20, 16, 50, 50))
+        >>> out = dropout_grad(in)
+    """
+    @prim_attr_register
+    def __init__(self, drop_prob=0):
+        self.drop_prob = validator.check_number_range("drop_prob", drop_prob, 0, 1, Rel.INC_BOTH, self.name)
+
+    def infer_shape(self, dy_shape, mask_shape):
+        return dy_shape
+
+    def infer_dtype(self, dy_dtype, mask_dtype):
+        valid_types = (mstype.float16, mstype.float32)
+        validator.check_tensor_type_same({"dy_dtype": dy_dtype}, valid_types, self.name)
+        return dy_dtype

tests/ut/python/nn/test_dropout.py

@@ -17,7 +17,9 @@ import numpy as np
 import pytest
 import mindspore.nn as nn
 from mindspore import Tensor
+from mindspore import context
 
+context.set_context(device_target="Ascend")
 
 def test_check_dropout_3():
     Tensor(np.ones([20, 16, 50]).astype(np.int32))

tests/ut/python/pynative_mode/nn/test_dropout.py

@@ -19,26 +19,26 @@ from mindspore.common.api import _executor
 import mindspore.nn as nn
 from mindspore import Tensor
 from mindspore import dtype as mstype
+from mindspore import context
+
+context.set_context(device_target="Ascend")
 
 def test_check_dropout_1():
     x = Tensor(np.ones([20, 16, 50]), mstype.float32)
     m = nn.Dropout(0.8)
-    with pytest.raises(NotImplementedError):
+    m(x)
-        m(x)
 
 
 def test_check_dropout_2():
     x = Tensor(np.ones([20, 16, 50]), mstype.float32)
     m = nn.Dropout(0.3, seed0=1)
-    with pytest.raises(NotImplementedError):
+    m(x)
-        m(x)
 
 
 def test_check_dropout_3():
     x = Tensor(np.ones([20, 16, 50]), mstype.float32)
     m = nn.Dropout(0.3, seed0=1, seed1=1)
-    with pytest.raises(NotImplementedError):
+    m(x)
-        m(x)
 
 
 class Net_Dropout(nn.Cell):