Source code for mindspore.nn.wrap.cell_wrapper

# Copyright 2020 Huawei Technologies Co., Ltd
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"""Cell_wrapper."""
from types import FunctionType, MethodType

from mindspore import log as logger
from mindspore.parallel._utils import (_get_device_num, _get_gradients_mean,
                                       _get_parallel_mode, _get_enable_parallel_optimizer)
from mindspore.context import ParallelMode
from mindspore._checkparam import Validator as validator
from mindspore import ops, nn
from ...common import dtype as mstype
from ...common.parameter import Parameter, ParameterTuple
from ...ops.primitive import constexpr
from ...ops import composite as C
from ...ops import functional as F
from ...ops import operations as P
from ...ops.operations.comm_ops import _VirtualDataset
from ..cell import Cell
from .grad_reducer import DistributedGradReducer

_get_datatype = C.MultitypeFuncGraph("_get_datatype")


@_get_datatype.register("Tensor")
def _tensors_get_datatype(param):
    """
    Acquire parameter datatype.

    Args:
        param (Tensor): The parameter before operation.

    Returns:
        mstype, the datatype of parameter.
    """
    return F.dtype(param)


_cast_datatype = C.MultitypeFuncGraph("_cast_datatype")


@_cast_datatype.register("TypeType", "Tensor")
def _tensors_cast_datatype(datatype, param):
    """
    Cast gradient to datatype.

    Args:
        datatype (mstype): the destination datatype of parameter.
        param (Tensor): The parameter before operation.

    Returns:
        Tensor, the parameter after operation.
    """
    return F.cast(param, datatype)


[docs]class WithLossCell(Cell): r""" Cell with loss function. Wraps the network with loss function. This Cell accepts data and label as inputs and the computed loss will be returned. Args: backbone (Cell): The backbone network to wrap. loss_fn (Cell): The loss function used to compute loss. Inputs: - **data** (Tensor) - Tensor of shape :math:`(N, \ldots)`. - **label** (Tensor) - Tensor of shape :math:`(N, \ldots)`. Outputs: Tensor, a tensor means the loss value, the shape of which is usually :math:`()`. Raises: TypeError: If dtype of `data` or `label` is neither float16 nor float32. Supported Platforms: ``Ascend`` ``GPU`` ``CPU`` Examples: >>> net = Net() >>> loss_fn = nn.SoftmaxCrossEntropyWithLogits(sparse=False) >>> net_with_criterion = nn.WithLossCell(net, loss_fn) >>> >>> batch_size = 2 >>> data = Tensor(np.ones([batch_size, 1, 32, 32]).astype(np.float32) * 0.01) >>> label = Tensor(np.ones([batch_size, 10]).astype(np.float32)) >>> >>> output_data = net_with_criterion(data, label) """ def __init__(self, backbone, loss_fn): super(WithLossCell, self).__init__(auto_prefix=False) self._backbone = backbone self._loss_fn = loss_fn def construct(self, data, label): out = self._backbone(data) return self._loss_fn(out, label) @property def backbone_network(self): """ Get the backbone network. Returns: Cell, the backbone network. """ return self._backbone
[docs]class WithGradCell(Cell): r""" Cell that returns the gradients. Wraps the network with backward cell to compute gradients. A network with a loss function is necessary as argument. If loss function in None, the network must be a wrapper of network and loss function. This Cell accepts '\*inputs' as inputs and returns gradients for each trainable parameter. Note: Run in PyNative mode. Args: network (Cell): The target network to wrap. The network only supports single output. loss_fn (Cell): Primitive loss function used to compute gradients. Default: None. sens (Union[None, Tensor, Scalar, Tuple ...]): The sensitive for backpropagation, the type and shape must be same as the `network` output. If None, we will fill one to a same type shape of output value. Default: None. Inputs: - **(\*inputs)** (Tuple(Tensor)) - Tuple of input tensors with shape :math:`(N, \ldots)`. Outputs: list, a list of Tensors with identical shapes as trainable weights. Raises: TypeError: If `sens` is not one of None, Tensor, Scalar or Tuple. Supported Platforms: ``Ascend`` ``GPU`` ``CPU`` Examples: >>> # For a defined network Net without loss function >>> net = Net() >>> loss_fn = nn.SoftmaxCrossEntropyWithLogits() >>> grad_net = nn.WithGradCell(net, loss_fn) >>> >>> # For a network wrapped with loss function >>> net = Net() >>> net_with_criterion = nn.WithLossCell(net, loss_fn) >>> grad_net = nn.WithGradCell(net_with_criterion) """ def __init__(self, network, loss_fn=None, sens=None): super(WithGradCell, self).__init__(auto_prefix=False) self.network = network self.loss_fn = loss_fn self.weights = ParameterTuple(network.trainable_params()) self.grad = C.GradOperation(get_by_list=True, sens_param=(sens is not None)) self.sens = sens if loss_fn is None: self.network_with_loss = network else: self.network_with_loss = WithLossCell(self.network, self.loss_fn) self.network_with_loss.set_train() def construct(self, *inputs): weights = self.weights if self.sens is None: grads = self.grad(self.network_with_loss, weights)(*inputs) else: grads = self.grad(self.network_with_loss, weights)(*inputs, self.sens) return grads
[docs]class ForwardValueAndGrad(Cell): r""" Encapsulate training network. Including the network and a gradient function. The resulting Cell is trained with input '\*inputs'. The backward graph will be created in the gradient function to calculating gradient. Args: network (Cell): The training network. weights (ParameterTuple): The parameters of the training network that need to calculate the gradient. Default: None. get_all (bool): If True, get all the gradients with respect to inputs. Default: False. get_by_list (bool): If True, get all the gradients with respect to Parameter variables. If get_all and get_by_list are both False, get the gradient with respect to first input. If get_all and get_by_list are both True, get the gradients with respect to inputs and Parameter variables at the same time in the form of ((gradients with respect to inputs), (gradients with respect to parameters)). Default: False. sens_param (bool): Whether to append sensitivity (gradient with respect to output) as input. If sens_param is False, a 'ones_like(outputs)' sensitivity will be attached automatically. Default: False. If the sens_param is True, a sensitivity (gradient with respect to output) needs to be transferred through the input parameter. Inputs: - **(\*inputs)** (Tuple(Tensor...)) - Tuple of inputs with shape :math:`(N, \ldots)`. - **(sens)** - A sensitivity (gradient with respect to output) as the input of backpropagation. If network has single output, the sens is a tensor. If network has multiple outputs, the sens is the tuple(tensor). Outputs: - **forward value** - The result of network forward running. - **gradients** (tuple(tensor)) - The gradients of network parameters and inputs. Supported Platforms: ``Ascend`` ``GPU`` ``CPU`` Examples: >>> import numpy as np >>> from mindspore import Tensor, nn, common, ops, ParameterTuple, Parameter >>> >>> class Net(nn.Cell): ... def __init__(self): ... super(Net, self).__init__() ... self.weight = Parameter(Tensor(np.ones([2, 2]).astype(np.float32)), name="weight") ... self.matmul = ops.MatMul() ... ... def construct(self, x): ... out = self.matmul(x, self.weight) ... return out ... >>> net = Net() >>> criterion = nn.SoftmaxCrossEntropyWithLogits() >>> net_with_criterion = nn.WithLossCell(net, criterion) >>> weight = ParameterTuple(net.trainable_params()) >>> train_network = nn.ForwardValueAndGrad(net_with_criterion, weights=weight, get_all=True, get_by_list=True) >>> inputs = Tensor(np.ones([1, 2]).astype(np.float32)) >>> labels = Tensor(np.zeros([1, 2]).astype(np.float32)) >>> result = train_network(inputs, labels) >>> print(result) (Tensor(shape=[1], dtype=Float32, value= [ 0.00000000e+00]), ((Tensor(shape=[1, 2], dtype=Float32, value= [[ 1.00000000e+00, 1.00000000e+00]]), Tensor(shape=[1, 2], dtype=Float32, value= [[ 0.00000000e+00, 0.00000000e+00]])), (Tensor(shape=[2, 2], dtype=Float32, value= [[ 5.00000000e-01, 5.00000000e-01], [ 5.00000000e-01, 5.00000000e-01]]),))) """ def __init__(self, network, weights=None, get_all=False, get_by_list=False, sens_param=False): super(ForwardValueAndGrad, self).__init__(auto_prefix=False) if not isinstance(network, (Cell, FunctionType, MethodType)): raise TypeError(f"For 'ForwardValueAndGrad', " f"the argument 'network' should be cell, function type or method type, " f"but got '{type(network)}'") if not isinstance(get_all, bool): raise TypeError(f"For 'ForwardValueAndGrad', " f"the type of 'get_all' should be bool, but got '{type(get_all)}'") if not isinstance(get_by_list, bool): raise TypeError(f"For 'ForwardValueAndGrad', " f"the type of 'get_by_list' should be bool, but got '{type(get_by_list)}'") if get_by_list and not isinstance(weights, ParameterTuple): raise TypeError(f"For 'ForwardValueAndGrad', " f"when 'get_by_list' is set to True, the argument 'weights' should be " f"ParameterTuple type, but got '{type(weights)}'") self.network = network if isinstance(network, Cell): self.network.set_grad() self.weights = weights self.get_all = get_all self.get_by_list = get_by_list self.sens_param = sens_param self.grad = C.GradOperation(get_all=self.get_all, get_by_list=self.get_by_list, sens_param=self.sens_param) def construct(self, *inputs): grad_inputs = inputs if self.sens_param: inputs = inputs[:-1] loss = self.network(*inputs) if self.get_by_list: grads = self.grad(self.network, self.weights)(*grad_inputs) else: grads = self.grad(self.network)(*grad_inputs) return loss, grads
[docs]class TrainOneStepCell(Cell): r""" Network training package class. Wraps the `network` with the `optimizer`. The resulting Cell is trained with input '\*inputs'. The backward graph will be created in the construct function to update the parameter. Different parallel modes are available for training. Args: network (Cell): The training network. The network only supports single output. optimizer (Union[Cell]): Optimizer for updating the network parameters. sens (numbers.Number): The scaling number to be filled as the input of backpropagation. Default value is 1.0. Inputs: - **(\*inputs)** (Tuple(Tensor)) - Tuple of input tensors with shape :math:`(N, \ldots)`. Outputs: Tensor, a tensor means the loss value, the shape of which is usually :math:`()`. Raises: TypeError: If `sens` is not a numbers.Number. Supported Platforms: ``Ascend`` ``GPU`` ``CPU`` Examples: >>> net = Net() >>> loss_fn = nn.SoftmaxCrossEntropyWithLogits() >>> optim = nn.Momentum(net.trainable_params(), learning_rate=0.1, momentum=0.9) >>> #1) Using the WithLossCell provided by MindSpore >>> loss_net = nn.WithLossCell(net, loss_fn) >>> train_net = nn.TrainOneStepCell(loss_net, optim) >>> >>> #2) Using user-defined WithLossCell >>> class MyWithLossCell(Cell): ... def __init__(self, backbone, loss_fn): ... super(MyWithLossCell, self).__init__(auto_prefix=False) ... self._backbone = backbone ... self._loss_fn = loss_fn ... ... def construct(self, x, y, label): ... out = self._backbone(x, y) ... return self._loss_fn(out, label) ... ... @property ... def backbone_network(self): ... return self._backbone ... >>> loss_net = MyWithLossCell(net, loss_fn) >>> train_net = nn.TrainOneStepCell(loss_net, optim) """ def __init__(self, network, optimizer, sens=1.0): super(TrainOneStepCell, self).__init__(auto_prefix=False) self.network = network self.network.set_grad() self.optimizer = optimizer self.weights = self.optimizer.parameters self.grad = C.GradOperation(get_by_list=True, sens_param=True) self.sens = sens self.reducer_flag = False self.grad_reducer = F.identity self.parallel_mode = _get_parallel_mode() self.reducer_flag = self.parallel_mode in (ParallelMode.DATA_PARALLEL, ParallelMode.HYBRID_PARALLEL) if self.reducer_flag: self.mean = _get_gradients_mean() self.degree = _get_device_num() if isinstance(self.optimizer, (nn.AdaSumByGradWrapCell, nn.AdaSumByDeltaWeightWrapCell)): from mindspore.communication.management import get_group_size, create_group, get_rank group_number = get_group_size() // 8 self.degree = int(self.degree / group_number) group_list = [list(range(x * self.degree, (x + 1) * self.degree)) for x in range(group_number)] current_index = get_rank() // 8 server_group_name = "allreduce_" + str(current_index) create_group(server_group_name, group_list[current_index]) self.grad_reducer = DistributedGradReducer(self.weights, self.mean, self.degree, group=server_group_name) else: self.grad_reducer = DistributedGradReducer(self.weights, self.mean, self.degree) def construct(self, *inputs): loss = self.network(*inputs) sens = F.fill(loss.dtype, loss.shape, self.sens) grads = self.grad(self.network, self.weights)(*inputs, sens) grads = self.grad_reducer(grads) loss = F.depend(loss, self.optimizer(grads)) return loss
[docs]class GetNextSingleOp(Cell): """ Cell to run for getting the next operation. For detailed information, refer to `mindspore.ops.GetNext`. Args: dataset_types (list[:class:`mindspore.dtype`]): The types of dataset. dataset_shapes (list[tuple[int]]): The shapes of dataset. queue_name (str): Queue name to fetch the data. Outputs: tuple[Tensor], the data get from Dataset. Supported Platforms: ``Ascend`` ``GPU`` Examples: >>> import mindspore >>> from mindspore import ops, nn >>> from mindspore import dataset as ds >>> from mindspore.common import dtype as mstype >>> >>> data_path = "/path/to/MNIST_Data/train/" >>> train_dataset = ds.MnistDataset(data_path, num_samples=10) >>> dataset_helper = mindspore.DatasetHelper(train_dataset, dataset_sink_mode=True) >>> dataset = dataset_helper.iter.dataset >>> dataset_types, dataset_shapes = dataset_helper.types_shapes() >>> queue_name = dataset.__transfer_dataset__.queue_name >>> get_next_single_op_net = nn.GetNextSingleOp(dataset_types, dataset_shapes, queue_name) >>> data, label = get_next_single_op_net() >>> relu = ops.ReLU() >>> result = relu(data.astype(mstype.float32)) >>> print(result.shape) (28, 28, 1) """ def __init__(self, dataset_types, dataset_shapes, queue_name): super(GetNextSingleOp, self).__init__() self.get_next = P.GetNext(dataset_types, dataset_shapes, len(dataset_types), queue_name) def construct(self): return self.get_next()
class _VirtualDatasetCell(Cell): """ Wrap the network with virtual dataset to convert data parallel layout to model parallel layout. _VirtualDataset is a virtual Primitive, it does not exist in the final executing graph. Inputs and outputs of _VirtualDataset are distributed in data parallel pattern, tensor redistribution Primitives is inserted dynamically during the graph compile process. Note: Only used in semi auto parallel and auto parallel mode. Args: backbone (Cell): The target network to wrap. Examples: >>> net = Net() >>> net = _VirtualDatasetCell(net) """ def __init__(self, backbone): super(_VirtualDatasetCell, self).__init__(auto_prefix=False) self._backbone = backbone self._virtual_dataset = _VirtualDataset() def construct(self, *inputs): output = self._virtual_dataset(*inputs) return self._backbone(*output) @constexpr def _check_shape_value_on_axis_divided_by_target_value(input_shape, dim, param_name, cls_name, target_value): if input_shape[dim] % target_value != 0: raise ValueError(f"For MicroBatchInterleaved initialization, " f"{cls_name} {param_name} at {dim} shape should be divided by {target_value}, " f"but got {input_shape[dim]}") return True class _MicroBatch(Cell): """ transform mini-batch to micro-batch in pipeline parallel. Args: params (micro_size): The number of micro-batch. """ def __init__(self, micro_size): super(_MicroBatch, self).__init__() self.shape = P.Shape() self.micro_size = micro_size self.strided_slice = P.StridedSlice() def construct(self, i, *inputs): micro_inputs = () for each_input in inputs: input_shape = self.shape(each_input) _check_shape_value_on_axis_divided_by_target_value(input_shape, 0, "inputs", self.cls_name, self.micro_size) micro_batch_begin = i * input_shape[0] // self.micro_size micro_batch_end = (i + 1) * input_shape[0] // self.micro_size strided_slice_begin = (micro_batch_begin,) strided_slice_strides = (1,) for _ in range(len(input_shape) - 1): strided_slice_begin += (0,) strided_slice_strides += (1,) strided_slice_end = (micro_batch_end,) strided_slice_end += input_shape[1:] micro_input = self.strided_slice(each_input, strided_slice_begin, strided_slice_end, strided_slice_strides) micro_inputs += (micro_input,) return micro_inputs
[docs]class MicroBatchInterleaved(Cell): """ Wrap the network with Batch Size. Args: network (Cell): The target network to wrap. interleave_num (int): split num of batch size. Default: 2. Supported Platforms: ``Ascend`` ``GPU`` Examples: >>> net = Net() >>> net = MicroBatchInterleaved(net, 4) """ def __init__(self, network, interleave_num=2): super(MicroBatchInterleaved, self).__init__(auto_prefix=False) if not isinstance(interleave_num, int): raise TypeError("For 'MicroBatchInterleaved', the argument 'interleave_num' should be integer, " "but got the type : {}.".format(type(interleave_num))) if interleave_num <= 0: raise ValueError("For 'MicroBatchInterleaved', the argument 'interleave_num' should be greater than 0, " "but got {}.".format(interleave_num)) self.network = network self.interleave_num = interleave_num self.interleave_inputs = nn.CellList() for _ in range(interleave_num): interleave_data = _MicroBatch(interleave_num) interleave_data.strided_slice.add_prim_attr("strided_slice_flag", True) self.interleave_inputs.append(interleave_data) def construct(self, *inputs): output = 0.0 for i in range(self.interleave_num): interleave_input = self.interleave_inputs[i](i, *inputs) output += self.network(*interleave_input) return output
[docs]class PipelineCell(Cell): """ Wrap the network with Micro Batch. Note: micro_size must be greater or equal to pipeline stages. Args: network (Cell): The target network to wrap. micro_size (int): MicroBatch size. Supported Platforms: ``Ascend`` ``GPU`` Examples: >>> net = Net() >>> net = PipelineCell(net, 4) """ def __init__(self, network, micro_size): super(PipelineCell, self).__init__(auto_prefix=False) self.network = network self.micro_inputs = nn.CellList() self.micro_size = micro_size self.add_list = [] for i in range(micro_size): micro_input = _MicroBatch(micro_size) self.micro_inputs.append(micro_input) self.add = P.Add().add_prim_attr("pipeline_end", i) self.add_list.append(self.add) def construct(self, *inputs): ret = None for i in range(self.micro_size): micro_input = self.micro_inputs[i](i, *inputs) output = self.network(*micro_input) if ret is not None: ret = self.add_list[i](ret, output) else: ret = output return ret
def _pipeline_clear_grad(accu_grad, grad): accu_grad = F.depend(accu_grad, grad) zeros = F.tensor_mul(accu_grad, 0.0) return F.assign(accu_grad, zeros) class _TrainPipelineAccuStepCell(TrainOneStepCell): """ Wraps the network with an optimizer in pipeline mode. """ def __init__(self, network, optimizer, sens=1.0): super(_TrainPipelineAccuStepCell, self).__init__(network, optimizer, sens) self.accu_grads = self.weights.clone(prefix="accu_grads", init="zeros") self.hyper_map = ops.HyperMap() self.opt_shard = _get_enable_parallel_optimizer() def construct(self, *inputs): weights = self.weights loss = self.network(*inputs) sens = ops.Fill()(ops.DType()(loss), ops.Shape()(loss), self.sens) grads = self.grad(self.network, weights)(*inputs, sens) accu_grads = ops.depend(self.accu_grads, grads) if self.opt_shard: succ = self.optimizer(grads) else: succ = self.optimizer(accu_grads) loss = ops.depend(loss, succ) clear = self.hyper_map(_pipeline_clear_grad, accu_grads, grads) loss = ops.depend(loss, clear) return loss class VirtualDatasetCellTriple(Cell): """ Wrap the network with virtual dataset to convert data parallel layout to model parallel layout. VirtualDatasetCellTriple is a virtual Primitive, it does not exist in the final executing graph. Inputs and outputs of VirtualDatasetCellTriple are distributed in data parallel pattern, tensor redistribution Primitives is inserted dynamically during the graph compile process. Note: Only used in semi auto parallel and auto parallel mode. There are three inputs, as contrary to two inputs in _VirtualDatasetCell. Args: backbone (Cell): The target network to wrap. Examples: >>> net = Net() >>> net = VirtualDatasetCellTriple(net) """ def __init__(self, backbone): super(VirtualDatasetCellTriple, self).__init__(auto_prefix=False) logger.warning("WARN_DEPRECATED: The usage of VirtualDatasetCellTriple is deprecated.") self._backbone = backbone def construct(self, a, b, c): return self._backbone(a, b, c)
[docs]class WithEvalCell(Cell): r""" Wraps the forward network with the loss function. It returns loss, forward output and label to calculate the metrics. Args: network (Cell): The forward network. loss_fn (Cell): The loss function. add_cast_fp32 (bool): Whether to adjust the data type to float32. Default: False. Inputs: - **data** (Tensor) - Tensor of shape :math:`(N, \ldots)`. - **label** (Tensor) - Tensor of shape :math:`(N, \ldots)`. Outputs: Tuple(Tensor), containing a scalar loss Tensor, a network output Tensor of shape :math:`(N, \ldots)` and a label Tensor of shape :math:`(N, \ldots)`. Raises: TypeError: If `add_cast_fp32` is not a bool. Supported Platforms: ``Ascend`` ``GPU`` ``CPU`` Examples: >>> # Forward network without loss function >>> net = Net() >>> loss_fn = nn.SoftmaxCrossEntropyWithLogits() >>> eval_net = nn.WithEvalCell(net, loss_fn) """ def __init__(self, network, loss_fn, add_cast_fp32=False): super(WithEvalCell, self).__init__(auto_prefix=False) self._network = network self._loss_fn = loss_fn self.add_cast_fp32 = validator.check_value_type("add_cast_fp32", add_cast_fp32, [bool], self.cls_name) def construct(self, data, label): outputs = self._network(data) if self.add_cast_fp32: label = F.mixed_precision_cast(mstype.float32, label) outputs = F.cast(outputs, mstype.float32) loss = self._loss_fn(outputs, label) return loss, outputs, label
[docs]class ParameterUpdate(Cell): """ Cell that updates parameter. With this Cell, one can manually update `param` with the input `Tensor`. Args: param (Parameter): The parameter to be updated manually. Inputs: - **x** (Tensor) - A tensor whose shape and type are the same with `param`. Outputs: Tensor, the input `x`. Raises: KeyError: If parameter with the specified name does not exist. Supported Platforms: ``Ascend`` ``GPU`` ``CPU`` Examples: >>> import numpy as np >>> import mindspore >>> from mindspore import nn, Tensor >>> network = nn.Dense(3, 4) >>> param = network.parameters_dict()['weight'] >>> update = nn.ParameterUpdate(param) >>> update.phase = "update_param" >>> weight = Tensor(np.arange(12).reshape((4, 3)), mindspore.float32) >>> output = update(weight) >>> print(output) [[ 0. 1. 2.] [ 3. 4. 5.] [ 6. 7. 8.] [ 9. 10. 11.]] """ def __init__(self, param): super(ParameterUpdate, self).__init__(auto_prefix=False) if not isinstance(param, Parameter): raise TypeError("For 'ParameterUpdate', 'param' must be 'Parameter', but got {}.".format(type(param))) self._param = param def construct(self, x): F.assign(self._param, x) return x
class _BroadCastCell(Cell): """ Broadcast the parameters from device 0 to other devices. Args: params (list): The parameters of Net. """ def __init__(self, params): super(_BroadCastCell, self).__init__() from mindspore.communication.management import get_group_size, create_group from mindspore import context self.map_ = C.Map() self.params = tuple(params) if context.get_context("device_target") == "Ascend" and context.get_context("mode") != context.PYNATIVE_MODE: rank_list = [id for id in range(0, get_group_size())] create_group("BroadcastWorldGroup", rank_list) self.broadcast = P.Broadcast(0, group="BroadcastWorldGroup") else: self.broadcast = P.Broadcast(0) def construct(self): datatypes = self.map_(F.partial(_get_datatype), self.params) params = self.map_(F.partial(_cast_datatype, mstype.float32), self.params) params = self.broadcast(params) new_params = self.map_(F.partial(_cast_datatype), datatypes, params) return new_params