# Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. from paddle.nn import functional as F from paddle.incubate.nn import functional as incubate_f from paddle.nn import Layer from paddle.framework import ParamAttr import paddle from paddle.nn.layer.transformer import _convert_attention_mask, _convert_param_attr_to_list from paddle.nn.initializer import Constant import collections # for distributed tensor model parallel def _set_var_distributed(var): if var is None: return var.is_distributed = True # NOTE: use current_block and find_var_recursive to support while_loop startup_block = paddle.static.default_startup_program().current_block() main_block = paddle.static.default_main_program().current_block() startup_block._find_var_recursive(var.name).is_distributed = True main_block._find_var_recursive(var.name).is_distributed = True class FusedMultiHeadAttention(Layer): """ Attention mapps queries and a set of key-value pairs to outputs, and Multi-Head Attention performs multiple parallel attention to jointly attending to information from different representation subspaces. Please refer to `Attention Is All You Need `_ for more details. Parameters: embed_dim (int): The expected feature size in the input and output. num_heads (int): The number of heads in multi-head attention. dropout_rate (float, optional): The dropout probability used on attention weights to drop some attention targets for the dropout after attention. 0 for no dropout. Default 0.5. attn_dropout_rate (float, optional): The dropout probability used on attention weights to drop some attention targets for the dropout in attention. 0 for no dropout. Default 0.5. kdim (int, optional): The feature size in key. If None, assumed equal to `embed_dim`. Default None. vdim (int, optional): The feature size in value. If None, assumed equal to `embed_dim`. Default None. normalize_before (bool, optional): Indicate whether it is pre_layer_norm (True) or post_layer_norm architecture (False). Default False. need_weights (bool, optional): Indicate whether to return the attention weights. Now, only False is supported. Default False. qkv_weight_attr(ParamAttr, optional): To specify the weight parameter property for QKV projection computation. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. qkv_bias_attr(ParamAttr|bool, optional): To specify the bias parameter property for QKV projection computation. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. linear_weight_attr(ParamAttr, optional): To specify the weight parameter property for linear projection computation. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. linear_bias_attr(ParamAttr|bool, optional): To specify the bias parameter property for linear projection computation. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. pre_ln_scale_attr(ParamAttr, optional): To specify the weight parameter property for pre_layer_norm computation. Otherwise, all layers both use it as `attr` to create parameters. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. pre_ln_bias_attr(ParamAttr|bool, optional): To specify the bias parameter property for pre_layer_norm computation. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. ln_scale_attr(ParamAttr, optional): To specify the weight parameter property for post_layer_norm computation. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. ln_bias_attr(ParamAttr|bool, optional): To specify the bias parameter property for post_layer_norm computation. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. epsilon (float, optional): The small value added to the variance to prevent division by zero. Default: 1e-05. nranks (int, optional): Distributed tensor model parallel nranks. Default is 1, means not using tensor parallel. ring_id (int, optional): For distributed tensor model parallel. Default is -1, means not using tensor parallel. Examples: .. code-block:: python # required: gpu import paddle # input: [batch_size, sequence_length, embed_dim] query = paddle.rand((2, 4, 128)) # self attention mask: [batch_size, num_heads, query_len, query_len] attn_mask = paddle.rand((2, 2, 4, 4)) multi_head_attn = paddle.incubate.nn.FusedMultiHeadAttention(128, 2) output = multi_head_attn(query, None, None, attn_mask=attn_mask) # [2, 4, 128] """ def __init__(self, embed_dim, num_heads, dropout_rate=0.5, attn_dropout_rate=0.5, kdim=None, vdim=None, normalize_before=False, need_weights=False, qkv_weight_attr=None, qkv_bias_attr=None, linear_weight_attr=None, linear_bias_attr=None, pre_ln_scale_attr=None, pre_ln_bias_attr=None, ln_scale_attr=None, ln_bias_attr=None, epsilon=1e-5, nranks=1, ring_id=-1, name=None): super(FusedMultiHeadAttention, self).__init__() assert embed_dim > 0, ("Expected embed_dim to be greater than 0, " "but received {}".format(embed_dim)) assert num_heads > 0, ("Expected nhead to be greater than 0, " "but received {}".format(num_heads)) self.normalize_before = normalize_before self._dtype = self._helper.get_default_dtype() self._epsilon = epsilon self._ring_id = ring_id self.embed_dim = embed_dim self.num_heads = num_heads self.head_dim = embed_dim // num_heads self.kdim = kdim self.vdim = vdim self.need_weights = need_weights assert self.head_dim * num_heads == embed_dim, "embed_dim must be divisible by num_heads" assert need_weights is False, "Only support need_weight is False now." # tensor model parallel assert num_heads % nranks == 0 num_heads = num_heads // nranks self.qkv_weight = self.create_parameter( shape=[3, num_heads, self.head_dim, embed_dim], attr=qkv_weight_attr, dtype=self._dtype, is_bias=False) self.qkv_bias = self.create_parameter( shape=[3, num_heads, self.head_dim], attr=qkv_bias_attr, dtype=self._dtype, is_bias=True) self.linear_weight = self.create_parameter( shape=[num_heads * self.head_dim, embed_dim], attr=linear_weight_attr, dtype=self._dtype, is_bias=False) self.linear_bias = self.create_parameter( shape=[embed_dim], attr=linear_bias_attr, dtype=self._dtype, is_bias=True) # tensor model parallel if nranks > 1: assert ring_id != -1 # column parallel _set_var_distributed(self.qkv_weight) _set_var_distributed(self.qkv_bias) # row parallel _set_var_distributed(self.linear_weight) if normalize_before: self.pre_ln_scale = self.create_parameter( attr=pre_ln_scale_attr, shape=[embed_dim], default_initializer=Constant(value=1.0)) self.pre_ln_bias = self.create_parameter( attr=pre_ln_bias_attr, shape=[embed_dim], is_bias=True) self.ln_scale = None self.ln_bias = None else: self.pre_ln_scale = None self.pre_ln_bias = None self.ln_scale = self.create_parameter( attr=ln_scale_attr, shape=[embed_dim], default_initializer=Constant(value=1.0)) self.ln_bias = self.create_parameter( attr=ln_bias_attr, shape=[embed_dim], is_bias=True) self.dropout_rate = dropout_rate self.attn_dropout_rate = attn_dropout_rate self.name = name def forward(self, query, key=None, value=None, attn_mask=None, cache=None): """ Applies multi-head attention to map queries and a set of key-value pairs to outputs. Parameters: query (Tensor): The queries for multi-head attention. It is a tensor with shape `[batch_size, query_length, embed_dim]`. The data type should be float32 or float64. key (Tensor, optional): The keys for multi-head attention. It is a tensor with shape `[batch_size, key_length, kdim]`. The data type should be float32 or float64. If None, use `query` as `key`. Default None. value (Tensor, optional): The values for multi-head attention. It is a tensor with shape `[batch_size, value_length, vdim]`. The data type should be float32 or float64. If None, use `query` as `value`. Default None. attn_mask (Tensor, optional): A tensor used in multi-head attention to prevents attention to some unwanted positions, usually the paddings or the subsequent positions. It is a tensor with shape broadcasted to `[batch_size, n_head, sequence_length, sequence_length]`. When the data type is bool, the unwanted positions have `False` values and the others have `True` values. When the data type is int, the unwanted positions have 0 values and the others have 1 values. When the data type is float, the unwanted positions have `-INF` values and the others have 0 values. It can be None when nothing wanted or needed to be prevented attention to. Default None. cache (MultiHeadAttention.Cache|MultiHeadAttention.StaticCache, optional): Now, only None is supported. Default None. Returns: Tensor|tuple: It is a tensor that has the same shape and data type \ as `query`, representing attention output. """ if attn_mask is not None: # Support bool or int mask attn_mask = _convert_attention_mask(attn_mask, query.dtype) out = incubate_f.fused_multi_head_attention( x=query, qkv_weight=self.qkv_weight, linear_weight=self.linear_weight, pre_layer_norm=self.normalize_before, pre_ln_scale=self.pre_ln_scale, pre_ln_bias=self.pre_ln_bias, ln_scale=self.ln_scale, ln_bias=self.ln_bias, pre_ln_epsilon=self._epsilon, qkv_bias=self.qkv_bias, linear_bias=self.linear_bias, cache_kv=cache, attn_mask=attn_mask, dropout_rate=self.dropout_rate, attn_dropout_rate=self.attn_dropout_rate, ln_epsilon=self._epsilon, training=self.training, ring_id=self._ring_id, name=self.name) return out def extra_repr(self): name_str = ', name={}'.format(self.name) if self.name else '' return 'embed_dim={}, num_heads={}, dropout_rate={}, attn_dropout_rate={}, epsilon={}, kdim={}, vdim={}, normalize_before={}, need_weights={}, dtype={}{}'.format( self.embed_dim, self.num_heads, self.dropout_rate, self.attn_dropout_rate, self._epsilon, self.kdim, self.vdim, self.normalize_before, self.need_weights, self._dtype, name_str) class FusedFeedForward(Layer): """ Parameters: d_model (int): The expected feature size in the input and output. dim_feedforward (int): The hidden layer size. dropout_rate (float, optional): The dropout probability used in pre-process and post-precess. Default 0.1 epsilon (float, optional): he small value added to the variance to prevent division by zero. Default: 1e-05. activation (str, optional): The activation function. Default relu. act_dropout_rate (float, optional): The dropout probability after activition. If None, use the value of `dropout_rate`. Default None normalize_before (bool, optional): Indicate whether to put layer normalization into, preprocessing or postprocessing. Default False linear1_weight_attr(ParamAttr, optional): To specify the weight parameter property for FFN first linear. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. linear1_bias_attr(ParamAttr|bool, optional): To specify the bias parameter property for FFN first linear. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. linear2_weight_attr(ParamAttr, optional): To specify the weight parameter property for FFN second linear. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. linear2_bias_attr(ParamAttr|bool, optional): To specify the bias parameter property for FFN second linear. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. ln1_scale_attr(ParamAttr, optional): To specify the weight parameter property for FFN pre_layer_norm. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. ln1_bias_attr(ParamAttr|bool, optional): To specify the bias parameter property for FFN pre_layer_norm. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. ln2_scale_attr(ParamAttr, optional): To specify the weight parameter property for FFN post_layer_norm. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. ln2_bias_attr(ParamAttr|bool, optional): To specify the bias parameter property for FFN layer_norm. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. nranks (int, optional): Distributed tensor model parallel nranks. Default is 1, means not using tensor parallel. ring_id (int, optional): For distributed tensor model parallel. Default is -1, means not using tensor parallel. name (str, optional): The default value is None. Normally there is no need for user to set this property. For more information, please refer to :ref:`api_guide_Name`. Examples: .. code-block:: python # required: gpu import paddle from paddle.incubate.nn import FusedFeedForward fused_feedforward_layer = FusedFeedForward(8, 8) x = paddle.rand((1, 8, 8)) out = fused_feedforward_layer(x) print(out.numpy().shape) # (1, 8, 8) """ def __init__(self, d_model, dim_feedforward, dropout_rate=0.1, epsilon=1e-05, activation="relu", act_dropout_rate=None, normalize_before=False, linear1_weight_attr=None, linear1_bias_attr=None, linear2_weight_attr=None, linear2_bias_attr=None, ln1_scale_attr=None, ln1_bias_attr=None, ln2_scale_attr=None, ln2_bias_attr=None, nranks=1, ring_id=-1, name=None): super(FusedFeedForward, self).__init__() assert d_model > 0, ( "Expected d_model to be greater than 0, but received {}".format( d_model)) assert dim_feedforward > 0, ( "Expected dim_feedforward to be greater than 0, but received {}". format(dim_feedforward)) self._dtype = self._helper.get_default_dtype() self._d_model = d_model assert dim_feedforward % nranks == 0 dim_feedforward = dim_feedforward // nranks self._dim_feedforward = dim_feedforward self._dropout_rate = dropout_rate self._act_dropout_rate = dropout_rate if act_dropout_rate is None else act_dropout_rate self._act_method = activation self._normalize_before = normalize_before self._epsilon = epsilon self._ring_id = ring_id self._linear1_weight = self.create_parameter( shape=[d_model, dim_feedforward], attr=linear1_weight_attr, dtype=self._dtype, is_bias=False) self._linear1_bias = self.create_parameter( shape=[dim_feedforward], attr=linear1_bias_attr, dtype=self._dtype, is_bias=True) self._linear2_weight = self.create_parameter( shape=[dim_feedforward, d_model], attr=linear2_weight_attr, dtype=self._dtype, is_bias=False) self._linear2_bias = self.create_parameter( shape=[d_model], attr=linear2_bias_attr, dtype=self._dtype, is_bias=True) if nranks > 1: assert ring_id != -1 # column parallel _set_var_distributed(self._linear1_weight) _set_var_distributed(self._linear1_bias) _set_var_distributed(self._linear2_weight) if normalize_before: self._ln1_scale = self.create_parameter( shape=[d_model], attr=ln1_scale_attr, is_bias=False, default_initializer=Constant(1.0)) self._ln1_bias = self.create_parameter( shape=[d_model], attr=ln1_bias_attr, is_bias=True) self._ln2_scale = None self._ln2_bias = None else: self._ln1_scale = None self._ln1_bias = None self._ln2_scale = self.create_parameter( shape=[d_model], attr=ln2_scale_attr, is_bias=False, default_initializer=Constant(1.0)) self._ln2_bias = self.create_parameter( shape=[d_model], attr=ln2_bias_attr, is_bias=True) self.name = name def forward(self, src, cache=None): out = incubate_f.fused_feedforward( src, self._linear1_weight, self._linear2_weight, self._linear1_bias, self._linear2_bias, self._ln1_scale, self._ln1_bias, self._ln2_scale, self._ln2_bias, dropout1_rate=self._act_dropout_rate, dropout2_rate=self._dropout_rate, activation=self._act_method, ln1_epsilon=self._epsilon, ln2_epsilon=self._epsilon, pre_layer_norm=self._normalize_before, training=self.training, ring_id=self._ring_id, name=self.name) return out def extra_repr(self): name_str = ', name={}'.format(self.name) if self.name else '' return 'd_model={}, dim_feedforward={}, dropout_rate={}, epsilon={}, activation={}, act_dropout_rate={}, normalize_before={}, dtype={}{}'.format( self._d_model, self._dim_feedforward, self._dropout_rate, self._epsilon, self._act_method, self._act_dropout_rate, self._normalize_before, self._dtype, name_str) class FusedTransformerEncoderLayer(Layer): """ FusedTransformerEncoderLayer is composed of two sub-layers which are self (multi-head) attention and feedforward network. Before and after each sub-layer, pre-process and post-precess would be applied on the input and output accordingly. If `normalize_before` is True, pre-process is layer normalization and post-precess includes dropout, residual connection. Otherwise, no pre-process and post-precess includes dropout, residual connection, layer normalization. Parameters: d_model (int): The expected feature size in the input and output. nhead (int): The number of heads in multi-head attention(MHA). dim_feedforward (int): The hidden layer size in the feedforward network(FFN). dropout_rate (float, optional): The dropout probability used in pre-process and post-precess of MHA and FFN sub-layer. Default 0.1 activation (str, optional): The activation function in the feedforward network. Default relu. attn_dropout_rate (float, optional): The dropout probability used in MHA to drop some attention target. If None, use the value of `dropout`. Default None act_dropout_rate (float, optional): The dropout probability used after FFN activition. If None, use the value of `dropout`. Default None normalize_before (bool, optional): Indicate whether to put layer normalization into preprocessing of MHA and FFN sub-layers. If True, pre-process is layer normalization and post-precess includes dropout, residual connection. Otherwise, no pre-process and post-precess includes dropout, residual connection, layer normalization. Default False weight_attr(ParamAttr|list|tuple, optional): To specify the weight parameter property. If it is a list/tuple, `weight_attr[0]` would be used as `weight_attr` for MHA, and `weight_attr[1]` would be used as `weight_attr` for linear in FFN. Otherwise, MHA and FFN both use it as `weight_attr` to create parameters. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr` . bias_attr (ParamAttr|list|tuple|bool, optional): To specify the bias parameter property. If it is a list/tuple, `bias_attr[0]` would be used as `bias_attr` for MHA, and `bias_attr[1]` would be used as `bias_attr` for linear in FFN. Otherwise, MHA and FFN both use it as `bias_attr` to create parameters. The `False` value means the corresponding layer would not have trainable bias parameter. See usage for details in :code:`ParamAttr` . Default: None, which means the default bias parameter property is used. Examples: .. code-block:: python # required: gpu import paddle from paddle.incubate.nn import FusedTransformerEncoderLayer # encoder input: [batch_size, src_len, d_model] enc_input = paddle.rand((2, 4, 128)) # self attention mask: [batch_size, n_head, src_len, src_len] attn_mask = paddle.rand((2, 2, 4, 4)) encoder_layer = FusedTransformerEncoderLayer(128, 2, 512) enc_output = encoder_layer(enc_input, attn_mask) # [2, 4, 128] """ def __init__(self, d_model, nhead, dim_feedforward, dropout_rate=0.1, activation="relu", attn_dropout_rate=None, act_dropout_rate=None, normalize_before=False, weight_attr=None, bias_attr=None): self._config = locals() self._config.pop("self") self._config.pop("__class__", None) # py3 super(FusedTransformerEncoderLayer, self).__init__() assert d_model > 0, ("Expected d_model to be greater than 0, " "but received {}".format(d_model)) assert nhead > 0, ("Expected nhead to be greater than 0, " "but received {}".format(nhead)) assert dim_feedforward > 0, ( "Expected dim_feedforward to be greater than 0, " "but received {}".format(dim_feedforward)) attn_dropout_rate = dropout_rate if attn_dropout_rate is None else attn_dropout_rate act_dropout_rate = dropout_rate if act_dropout_rate is None else act_dropout_rate self.normalize_before = normalize_before weight_attrs = _convert_param_attr_to_list(weight_attr, 2) bias_attrs = _convert_param_attr_to_list(bias_attr, 2) self.fused_attn = FusedMultiHeadAttention( d_model, nhead, dropout_rate=dropout_rate, attn_dropout_rate=attn_dropout_rate, normalize_before=self.normalize_before, qkv_weight_attr=weight_attrs[0], qkv_bias_attr=bias_attrs[0], linear_weight_attr=weight_attrs[0], linear_bias_attr=bias_attrs[0], pre_ln_scale_attr=weight_attrs[0], pre_ln_bias_attr=bias_attrs[0], ln_scale_attr=weight_attrs[0], ln_bias_attr=bias_attrs[0]) self.ffn = FusedFeedForward( d_model, dim_feedforward, dropout_rate=dropout_rate, activation=activation, act_dropout_rate=act_dropout_rate, normalize_before=self.normalize_before, linear1_weight_attr=weight_attrs[1], linear1_bias_attr=bias_attrs[1], linear2_weight_attr=weight_attrs[1], linear2_bias_attr=bias_attrs[1]) def forward(self, src, src_mask=None, cache=None): """ Applies a Transformer encoder layer on the input. Parameters: src (Tensor): The input of Transformer encoder layer. It is a tensor with shape `[batch_size, sequence_length, d_model]`. The data type should be float32 or float64. src_mask (Tensor, optional): A tensor used in multi-head attention to prevents attention to some unwanted positions, usually the paddings or the subsequent positions. It is a tensor with shape broadcasted to `[batch_size, n_head, sequence_length, sequence_length]`. When the data type is bool, the unwanted positions have `False` values and the others have `True` values. When the data type is int, the unwanted positions have 0 values and the others have 1 values. When the data type is float, the unwanted positions have `-INF` values and the others have 0 values. It can be None when nothing wanted or needed to be prevented attention to. Default None. cache (Tensor, optional): It is an instance of `MultiHeadAttention.Cache`. See `TransformerEncoderLayer.gen_cache` for more details. It is only used for inference and should be None for training. Default None. Returns: Tensor|tuple: It is a tensor that has the same shape and data type \ as `enc_input`, representing the output of Transformer encoder \ layer. Or a tuple if `cache` is not None, except for encoder \ layer output, the tuple includes the new cache which is same \ as input `cache` argument but `incremental_cache` has an \ incremental length. See `MultiHeadAttention.gen_cache` and \ `MultiHeadAttention.forward` for more details. """ src_mask = _convert_attention_mask(src_mask, src.dtype) if cache is None: attn_out = self.fused_attn(src, attn_mask=src_mask) else: attn_out, incremental_cache = self.fused_attn( src, attn_mask=src_mask, cache=cache) ffn_out = self.ffn(attn_out) return ffn_out if cache is None else (ffn_out, incremental_cache) class FusedTransformer(Layer): """ A Transformer model composed of an instance of `TransformerEncoder` and an instance of `TransformerDecoder`. While the embedding layer and output layer are not included. Please refer to `Attention is all you need `_ , and see `TransformerEncoder` and `TransformerDecoder` for more details. Users can configurate the model architecture with corresponding parameters. Note the usage of `normalize_before` representing where to apply layer normalization (in pre-process or post-precess of multi-head attention or FFN), and some transformer like models are different on this, such as `BERT `_ and `GPT2 `_ . The default architecture here places layer normalization in post-process and applies another layer normalization on the output of last encoder/decoder layer. Parameters: d_model (int, optional): The expected feature size in the encoder/decoder input and output. Default 512 nhead (int, optional): The number of heads in multi-head attention(MHA). Default 8 num_encoder_layers (int, optional): The number of layers in encoder. Default 6 num_decoder_layers (int, optional): The number of layers in decoder. Default 6 dim_feedforward (int, optional): The hidden layer size in the feedforward network(FFN). Default 2048 dropout (float, optional): The dropout probability used in pre-process and post-precess of MHA and FFN sub-layer. Default 0.1 activation (str, optional): The activation function in the feedforward network. Default relu. attn_dropout (float, optional): The dropout probability used in MHA to drop some attention target. If None, use the value of `dropout`. Default None act_dropout (float, optional): The dropout probability used after FFN activition. If None, use the value of `dropout`. Default None normalize_before (bool, optional): Indicate whether to put layer normalization into preprocessing of MHA and FFN sub-layers. If True, pre-process is layer normalization and post-precess includes dropout, residual connection. Otherwise, no pre-process and post-precess includes dropout, residual connection, layer normalization. Default False weight_attr(ParamAttr|list|tuple, optional): To specify the weight parameter property. If it is a list/tuple, the length of `weight_attr` could be 1, 2 or 3. If it is 3, `weight_attr[0]` would be used as `weight_attr` for self attention, `weight_attr[1]` would be used as `weight_attr` for cross attention of `TransformerDecoder`, and `weight_attr[2]` would be used as `weight_attr` for linear in FFN. If it is 2, `weight_attr[0]` would be used as `weight_attr` both for self attention and cross attntion and `weight_attr[1]` would be used as `weight_attr` for linear in FFN. If it is 1, `weight_attr[0]` would be used as `weight_attr` for self attention, cross attention and linear in FFN. Otherwise, the three sub-layers all uses it as `weight_attr` to create parameters. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr` . bias_attr (ParamAttr|list|tuple|bool, optional): To specify the bias parameter property. If it is a list/tuple, the length of `bias_attr` could be 1, 2 or 3. If it is 3, `bias_attr[0]` would be used as `bias_attr` for self attention, `bias_attr[1]` would be used as `bias_attr` for cross attention of `TransformerDecoder`, and `bias_attr[2]` would be used as `bias_attr` for linear in FFN. If it is 2, `bias_attr[0]` would be used as `bias_attr` both for self attention and cross attntion and `bias_attr[1]` would be used as `bias_attr` for linear in FFN. If it is 1, `bias_attr[0]` would be used as `bias_attr` for self attention, cross attention and linear in FFN. Otherwise, the three sub-layers all uses it as `bias_attr` to create parameters. The `False` value means the corresponding layer would not have trainable bias parameter. See usage for details in :code:`ParamAttr` . Default: None,which means the default bias parameter property is used. custom_encoder (Layer, optional): If custom encoder is provided, use it as the encoder. Default None custom_decoder (Layer, optional): If custom decoder is provided, use it as the decoder. Default None Examples: .. code-block:: python import paddle from paddle.nn import Transformer # src: [batch_size, tgt_len, d_model] enc_input = paddle.rand((2, 4, 128)) # tgt: [batch_size, src_len, d_model] dec_input = paddle.rand((2, 6, 128)) # src_mask: [batch_size, n_head, src_len, src_len] enc_self_attn_mask = paddle.rand((2, 2, 4, 4)) # tgt_mask: [batch_size, n_head, tgt_len, tgt_len] dec_self_attn_mask = paddle.rand((2, 2, 6, 6)) # memory_mask: [batch_size, n_head, tgt_len, src_len] cross_attn_mask = paddle.rand((2, 2, 6, 4)) transformer = Transformer(128, 2, 4, 4, 512) output = transformer(enc_input, dec_input, enc_self_attn_mask, dec_self_attn_mask, cross_attn_mask) # [2, 6, 128] """ def __init__(self, d_model=512, nhead=8, num_encoder_layers=6, num_decoder_layers=6, dim_feedforward=2048, dropout=0.1, activation="relu", attn_dropout=None, act_dropout=None, normalize_before=False, weight_attr=None, bias_attr=None, custom_encoder=None, custom_decoder=None): super(fusedTransformer, self).__init__() raise NotImplementedError() def forward(self, src, tgt, src_mask=None, tgt_mask=None, memory_mask=None): raise NotImplementedError() class FusedMultiTransformer(Layer): """ FusedMultiTransformer is composed of multi transformer layers which contains two sub-layers which are self (multi-head) attention and feedforward network. The function of one transformer layer is consistent with the following pseudo code: .. code-block:: python if pre_layer_norm: out = layer_norm(x) out = qkv_linear(out) + qkv_bias else: out = qkv_linear(x) + qkv_bias out = transpose(out, perm=[2, 0, 3, 1, 4]) # extract q, k and v from out. q = out[0:1, ::] k = out[1:2, ::] v = out[2:3, ::] out = q * k^t out = attn_mask + out out = softmax(out) out = dropout(out) out = out * v out = transpose(out, perm=[0, 2, 1, 3]) out = linear(out) if pre_layer_norm: out = x + dropout(out + bias) else: out = layer_norm(x + dropout(out + bias)) residual = out; if pre_layer_norm: out = ffn_layer_norm(out) out = ffn1_linear(out) out = dropout(activation(out + ffn1_bias)) out = ffn2_linear(out) out = residual + dropout(out + ffn2_bias) if not pre_layer_norm: out = ffn_layer_norm(out) Parameters: embed_dim (int): The expected feature size in the input and output. num_heads (int): The number of heads in multi-head attention(MHA). dim_feedforward (int): The hidden layer size in the feedforward network(FFN). dropout_rate (float, optional): The dropout probability used in pre-process and post-precess of MHA and FFN sub-layer. Default 0.0 activation (str, optional): The activation function in the feedforward network. Default "gelu". normalize_before (bool, optional): Indicate whether to put layer normalization into preprocessing of MHA and FFN sub-layers. If True, pre-process is layer normalization and post-precess includes dropout, residual connection. Otherwise, no pre-process and post-precess includes dropout, residual connection, layer normalization. Default True ln_scale_attrs(ParamAttr|list|tuple, optional): To specify the weight parameter property for Attention layer_norm. For Attention layer_norm weight, if it is a list/tuple, `attrs[0]` would be used as `attr` for transformer layer 0, and `attrs[1]` would be used as `attr` for transformer layer 1，etc. Otherwise, all layers both use it as `attr` to create parameters. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. ln_bias_attrs(ParamAttr|list|tuple|bool, optional): To specify the bias parameter property for Attention layer_norm. For Attention layer_norm bias, if it is a list/tuple, `attrs[0]` would be used as `attr` for transformer layer 0, and `attrs[1]` would be used as `attr` for transformer layer 1，etc. Otherwise, all layers both use it as `attr` to create parameters. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. qkv_weight_attrs(ParamAttr|list|tuple, optional): To specify the weight parameter property for Attention qkv computation. For Attention qkv weight, if it is a list/tuple, `attrs[0]` would be used as `attr` for transformer layer 0, and `attrs[1]` would be used as `attr` for transformer layer 1，etc. Otherwise, all layers both use it as `attr` to create parameters. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. qkv_bias_attrs(ParamAttr|list|tuple|bool, optional): To specify the bias parameter property for Attention qkv computation. For Attention qkv bias, if it is a list/tuple, `attrs[0]` would be used as `attr` for transformer layer 0, and `attrs[1]` would be used as `attr` for transformer layer 1，etc. Otherwise, all layers both use it as `attr` to create parameters. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. linear_weight_attrs(ParamAttr|list|tuple, optional): To specify the weight parameter property for Attention linear. For Attention linear weight, if it is a list/tuple, `attrs[0]` would be used as `attr` for transformer layer 0, and `attrs[1]` would be used as `attr` for transformer layer 1，etc. Otherwise, all layers both use it as `attr` to create parameters. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. linear_bias_attrs(ParamAttr|list|tuple|bool, optional): To specify the bias parameter property for Attention linear computation. For Attention linear bias, if it is a list/tuple, `attrs[0]` would be used as `attr` for transformer layer 0, and `attrs[1]` would be used as `attr` for transformer layer 1，etc. Otherwise, all layers both use it as `attr` to create parameters. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. ffn_ln_scale_attrs(ParamAttr|list|tuple, optional): To specify the weight parameter property for FFN layer_norm. For FFN layer_norm weight, if it is a list/tuple, `attrs[0]` would be used as `attr` for transformer layer 0, and `attrs[1]` would be used as `attr` for transformer layer 1，etc. Otherwise, all layers both use it as `attr` to create parameters. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. ffn_ln_bias_attrs(ParamAttr|list|tuple|bool, optional): To specify the bias parameter property for FFN layer_norm. For FFN layer_norm bias, if it is a list/tuple, `attrs[0]` would be used as `attr` for transformer layer 0, and `attrs[1]` would be used as `attr` for transformer layer 1，etc. Otherwise, all layers both use it as `attr` to create parameters. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. ffn1_weight_attrs(ParamAttr|list|tuple, optional): To specify the weight parameter property for FFN first linear. For FFN first linear weight, if it is a list/tuple, `attrs[0]` would be used as `attr` for transformer layer 0, and `attrs[1]` would be used as `attr` for transformer layer 1，etc. Otherwise, all layers both use it as `attr` to create parameters. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. ffn1_bias_attrs(ParamAttr|list|tuple|bool, optional): To specify the bias parameter property for FFN first linear. For FFN first linear bias, if it is a list/tuple, `attrs[0]` would be used as `attr` for transformer layer 0, and `attrs[1]` would be used as `attr` for transformer layer 1，etc. Otherwise, all layers both use it as `attr` to create parameters. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. ffn2_weight_attrs(ParamAttr|list|tuple, optional): To specify the weight parameter property for FFN second linear. For FFN second linear weight, if it is a list/tuple, `attrs[0]` would be used as `attr` for transformer layer 0, and `attrs[1]` would be used as `attr` for transformer layer 1，etc. Otherwise, all layers both use it as `attr` to create parameters. Default: None, which means the default weight parameter property is used. See usage for details in :code:`ParamAttr`. ffn2_bias_attrs(ParamAttr|list|tuple|bool, optional): To specify the bias parameter property for FFN second linear. For FFN second linear bias, if it is a list/tuple, `attrs[0]` would be used as `attr` for transformer layer 0, and `attrs[1]` would be used as `attr` for transformer layer 1，etc. Otherwise, all layers both use it as `attr` to create parameters. The `False` value means the corresponding layer would not have trainable bias parameter. Default: None, which means the default bias parameter property is used. See usage for details in :code:`ParamAttr`. epsilon (float, optional): Small float value added to denominator of the layer_norm to avoid dividing by zero. Default: 1e-05. num_layers (int, optional): The number of layers of the transformer. If `qkv_weight_attrs` is a list or tuple, the number of layers is obtained from `qkv_weight_attrs`. num_layers only takes effect when `qkv_weight_attrs` is not a list or tuple. Default: -1. nranks (int, optional): Distributed tensor model parallel nranks. Default is 1, means not using mp. ring_id (int, optional): For distributed tensor model parallel. Default is -1, means not using mp. name (str, optional): The default value is None. Normally there is no need for user to set this property. For more information, please refer to :ref:`api_guide_Name`. Examples: .. code-block:: python # required: gpu import paddle from paddle.incubate.nn import FusedMultiTransformer # encoder input: [batch_size, src_len, d_model] enc_input = paddle.rand((2, 4, 128)) # self attention mask: [batch_size, 1, src_len, src_len] attn_mask = paddle.rand((2, 1, 4, 4)) encoder_layers = FusedMultiTransformer(128, 2, 512, num_layers=1) enc_output = encoder_layers(enc_input, attn_mask) # [2, 4, 128] """ def __init__(self, embed_dim, num_heads, dim_feedforward, dropout_rate=0.0, activation="gelu", normalize_before=True, ln_scale_attrs=None, ln_bias_attrs=None, qkv_weight_attrs=None, qkv_bias_attrs=None, linear_weight_attrs=None, linear_bias_attrs=None, ffn_ln_scale_attrs=None, ffn_ln_bias_attrs=None, ffn1_weight_attrs=None, ffn1_bias_attrs=None, ffn2_weight_attrs=None, ffn2_bias_attrs=None, epsilon=1e-5, num_layers=-1, nranks=1, ring_id=-1, name=None): super(FusedMultiTransformer, self).__init__() assert embed_dim > 0, ("Expected embed_dim to be greater than 0, " "but received {}".format(embed_dim)) assert num_heads > 0, ("Expected nhead to be greater than 0, " "but received {}".format(num_heads)) assert dim_feedforward > 0, ( "Expected dim_feedforward to be greater than 0, but received {}". format(dim_feedforward)) self.normalize_before = normalize_before self._dtype = self._helper.get_default_dtype() self._epsilon = epsilon self._ring_id = ring_id self.embed_dim = embed_dim self.num_heads = num_heads self.head_dim = embed_dim // num_heads assert self.head_dim * num_heads == embed_dim, "embed_dim must be divisible by num_heads" # tensor model parallel if nranks > 1: assert ring_id != -1 assert num_heads % nranks == 0 assert dim_feedforward % nranks == 0 num_heads = num_heads // nranks dim_feedforward = dim_feedforward // nranks self._dim_feedforward = dim_feedforward if isinstance(qkv_weight_attrs, (list, tuple)): num_layers = len(qkv_weight_attrs) assert num_layers > 0 self.ln_scales, self.ln_biases = [], [] self.qkv_weights, self.qkv_biases = [], [] self.linear_weights, self.linear_biases = [], [] self.ffn_ln_scales, self.ffn_ln_biases = [], [] self.ffn1_weights, self.ffn1_biases = [], [] self.ffn2_weights, self.ffn2_biases = [], [] def get_attr(attrs, idx): if isinstance(attrs, (list, tuple)): assert len(attrs) == num_layers return attrs[idx] return attrs for i in range(num_layers): ln_scale_attr = get_attr(ln_scale_attrs, i) ln_bias_attr = get_attr(ln_bias_attrs, i) qkv_weight_attr = get_attr(qkv_weight_attrs, i) qkv_bias_attr = get_attr(qkv_bias_attrs, i) linear_weight_attr = get_attr(linear_weight_attrs, i) linear_bias_attr = get_attr(linear_bias_attrs, i) ffn_ln_scale_attr = get_attr(ffn_ln_scale_attrs, i) ffn_ln_bias_attr = get_attr(ffn_ln_bias_attrs, i) ffn1_weight_attr = get_attr(ffn1_weight_attrs, i) ffn1_bias_attr = get_attr(ffn1_bias_attrs, i) ffn2_weight_attr = get_attr(ffn2_weight_attrs, i) ffn2_bias_attr = get_attr(ffn2_bias_attrs, i) ln_scale = self.create_parameter( attr=ln_scale_attr, shape=[embed_dim], default_initializer=Constant(value=1.0)) ln_bias = self.create_parameter( attr=ln_bias_attr, shape=[embed_dim], is_bias=True) qkv_weight = self.create_parameter( shape=[3, num_heads, self.head_dim, embed_dim], attr=qkv_weight_attr, dtype=self._dtype, is_bias=False) qkv_bias = self.create_parameter( shape=[3, num_heads, self.head_dim], attr=qkv_bias_attr, dtype=self._dtype, is_bias=True) linear_weight = self.create_parameter( shape=[num_heads * self.head_dim, embed_dim], attr=linear_weight_attr, dtype=self._dtype, is_bias=False) linear_bias = self.create_parameter( shape=[embed_dim], attr=linear_bias_attr, dtype=self._dtype, is_bias=True) ffn_ln_scale = self.create_parameter( shape=[embed_dim], attr=ffn_ln_scale_attr, is_bias=False, default_initializer=Constant(1.0)) ffn_ln_bias = self.create_parameter( shape=[embed_dim], attr=ffn_ln_bias_attr, is_bias=True) ffn1_weight = self.create_parameter( shape=[embed_dim, dim_feedforward], attr=ffn1_weight_attr, dtype=self._dtype, is_bias=False) ffn1_bias = self.create_parameter( shape=[dim_feedforward], attr=ffn1_bias_attr, dtype=self._dtype, is_bias=True) ffn2_weight = self.create_parameter( shape=[dim_feedforward, embed_dim], attr=ffn2_weight_attr, dtype=self._dtype, is_bias=False) ffn2_bias = self.create_parameter( shape=[embed_dim], attr=ffn2_bias_attr, dtype=self._dtype, is_bias=True) # tensor model parallel if nranks > 1: # column parallel _set_var_distributed(qkv_weight) _set_var_distributed(qkv_bias) _set_var_distributed(ffn1_weight) _set_var_distributed(ffn1_bias) # row parallel _set_var_distributed(linear_weight) _set_var_distributed(ffn2_weight) self.ln_scales.append(ln_scale) self.ln_biases.append(ln_bias) self.qkv_weights.append(qkv_weight) self.qkv_biases.append(qkv_bias) self.linear_weights.append(linear_weight) self.linear_biases.append(linear_bias) self.ffn_ln_scales.append(ffn_ln_scale) self.ffn_ln_biases.append(ffn_ln_bias) self.ffn1_weights.append(ffn1_weight) self.ffn1_biases.append(ffn1_bias) self.ffn2_weights.append(ffn2_weight) self.ffn2_biases.append(ffn2_bias) self.dropout_rate = dropout_rate self.activation = activation self.name = name def forward(self, src, attn_mask=None, caches=None, time_step=None): """ Applies multi transformer layers on the input. Parameters: src (Tensor): The input of Transformer layers. It is a tensor with shape `[batch_size, sequence_length, d_model]`. The data type should be float16 or float32. attn_mask (Tensor, optional): A tensor used in multi-head attention to prevents attention to some unwanted positions, usually the paddings or the subsequent positions. It is a tensor with shape `[batch_size, 1, sequence_length, sequence_length]`. It can be None when nothing wanted or needed to be prevented attention to. Default None. caches (list(Tensor)|tuple(Tensor), optional): The cache structure tensors for the inference generation model. It is only used for inference and should be None for training. The shape is `[2, batch_size, num_head, max_seq_len, head_dim]`. Default None. time_step (Tensor, optional): The time step tensor for the generation model. Which used in decode stage, to represent the time step, that is, the real seq_len of CacheKV. The shape is `[1]`, must be in CPUPlace. Default None. Returns: Tensor|tuple: If `caches` is None, return a tensor that has the same shape and data type with `src`, representing the output of Transformer layers. If `caches` is not None, return the tuple (output, caches), which output is the output of Transformer layers, caches is inplace with input `caches`. """ if caches is not None: assert len(caches) == len(self.qkv_weights) out = incubate_f.fused_multi_transformer( src, self.ln_scales, self.ln_biases, self.qkv_weights, self.qkv_biases, self.linear_weights, self.linear_biases, self.ffn_ln_scales, self.ffn_ln_biases, self.ffn1_weights, self.ffn1_biases, self.ffn2_weights, self.ffn2_biases, pre_layer_norm=self.normalize_before, epsilon=self._epsilon, cache_kvs=caches, time_step=time_step, attn_mask=attn_mask, dropout_rate=self.dropout_rate, activation=self.activation, training=self.training, mode='upscale_in_train', ring_id=self._ring_id, name=self.name) return out