ColossalAI/colossalai/shardformer/modeling/t5.py

590 lines
29 KiB
Python

import warnings
from typing import Dict, List, Optional, Tuple, Union
import torch
from torch.nn import CrossEntropyLoss
from torch.utils.checkpoint import checkpoint
from transformers.modeling_outputs import (
BaseModelOutput,
BaseModelOutputWithPastAndCrossAttentions,
Seq2SeqLMOutput,
Seq2SeqModelOutput,
)
from transformers.models.t5.modeling_t5 import T5EncoderModel, T5ForConditionalGeneration, T5Model, T5Stack
from transformers.utils import logging
from colossalai.pipeline.stage_manager import PipelineStageManager
class T5PipelineForwards:
'''
This class serves as a micro library for forward function substitution of
T5 models under pipeline setting.
'''
@staticmethod
def t5_stack_forward(
self: T5Stack,
input_ids: Optional[torch.LongTensor] = None,
attention_mask: Optional[torch.FloatTensor] = None,
encoder_hidden_states: Optional[torch.Tensor] = None,
encoder_attention_mask: Optional[torch.FloatTensor] = None,
inputs_embeds: Optional[torch.FloatTensor] = None,
head_mask: Optional[torch.FloatTensor] = None,
cross_attn_head_mask: Optional[torch.Tensor] = None,
past_key_values: Optional[Tuple[Tuple[torch.FloatTensor]]] = None,
use_cache: Optional[bool] = False,
output_attentions: Optional[bool] = False,
output_hidden_states: Optional[bool] = False,
return_dict: Optional[bool] = None,
stage_manager: Optional[PipelineStageManager] = None,
hidden_states: Optional[torch.FloatTensor] = None,
position_bias: Optional[torch.Tensor] = None,
encoder_decoder_position_bias: Optional[torch.Tensor] = None,
stage_index: Optional[List[int]] = None,
decoder_starting_stage: Optional[int] = None,
) -> Union[Dict, Tuple, BaseModelOutputWithPastAndCrossAttentions]:
# This function is modified on the basis of transformers.models.t5.modeling_t5.T5Stack.forward.
# Please refer to original code of transformers for more details.
logger = logging.get_logger(__name__)
# TODO: left the recording kv-value tensors as () or None type, this feature may be added in the future.
if past_key_values:
logger.warning_once('Non-empty past_key_values is not supported for pipeline models at the moment.')
past_key_values = None
if output_attentions:
logger.warning_once('output_attentions=True is not supported for pipeline models at the moment.')
output_attentions = False
if output_hidden_states:
logger.warning_once('output_hidden_states=True is not supported for pipeline models at the moment.')
output_hidden_states = False
if use_cache:
logger.warning_once('use_cache=True is not supported for pipeline models at the moment.')
use_cache = False
if use_cache is True:
if not in_decoder:
raise ValueError(f"`use_cache` can only be set to `True` if {self} is used as a decoder")
if self.gradient_checkpointing and self.training:
if use_cache:
logger.warning_once(
"`use_cache=True` is incompatible with gradient checkpointing. Setting `use_cache=False`...")
use_cache = False
stage = stage_manager.stage
in_decoder = self.is_decoder
if in_decoder != (stage >= decoder_starting_stage):
raise ValueError("Config in T5Stack is not aligned with pipeline setting.")
# at_first_stage: current stage is the first stage of encoder/decoder, taking input_ids/input_embedds
# at_last_stage: current stage is the last stage of encoder/decoder, making outputs the same form as huggingface
at_first_stage = (stage == 0) or (stage == decoder_starting_stage)
at_last_stage = (stage == decoder_starting_stage - 1) or (stage == stage_manager.num_stages - 1)
# Process inputs if at the first stage of encoder/decoder.
if at_first_stage:
if input_ids is not None and inputs_embeds is not None:
err_msg_prefix = "decoder_" if in_decoder else ""
raise ValueError(
f"You cannot specify both {err_msg_prefix}input_ids and {err_msg_prefix}inputs_embeds at the same time"
)
elif input_ids is not None:
input_shape = input_ids.size()
input_ids = input_ids.view(-1, input_shape[-1])
elif inputs_embeds is not None:
input_shape = inputs_embeds.size()[:-1]
else:
err_msg_prefix = "decoder_" if in_decoder else ""
raise ValueError(
f"You have to specify either {err_msg_prefix}input_ids or {err_msg_prefix}inputs_embeds")
if inputs_embeds is None:
if self.embed_tokens is None:
raise ValueError("You have to initialize the model with valid token embeddings")
inputs_embeds = self.embed_tokens(input_ids)
batch_size, seq_length = input_shape
device = inputs_embeds.device
hidden_states = self.dropout(inputs_embeds)
else:
if hidden_states is None:
raise ValueError(
"hidden_states shouldn't be None for stages other than the first stage of encoder/decoder.")
input_shape = hidden_states.size()[:-1]
batch_size, seq_length = input_shape[0], input_shape[1]
device = hidden_states.device
# required mask seq length can be calculated via length of past
mask_seq_length = past_key_values[0][0].shape[2] + seq_length if past_key_values is not None else seq_length
if attention_mask is None:
attention_mask = torch.ones(batch_size, mask_seq_length, device=device)
if in_decoder and encoder_attention_mask is None and encoder_hidden_states is not None:
encoder_seq_length = encoder_hidden_states.shape[1]
encoder_attention_mask = torch.ones(batch_size, encoder_seq_length, device=device, dtype=torch.long)
# initialize past_key_values with `None` if past does not exist
if past_key_values is None:
past_key_values = [None] * len(self.block)
# We can provide a self-attention mask of dimensions [batch_size, from_seq_length, to_seq_length]
# ourselves in which case we just need to make it broadcastable to all heads.
extended_attention_mask = self.get_extended_attention_mask(attention_mask, input_shape)
# If a 2D or 3D attention mask is provided for the cross-attention
# we need to make broadcastable to [batch_size, num_heads, seq_length, seq_length]
if self.is_decoder and encoder_hidden_states is not None:
encoder_batch_size, encoder_sequence_length, _ = encoder_hidden_states.size()
encoder_hidden_shape = (encoder_batch_size, encoder_sequence_length)
if encoder_attention_mask is None:
encoder_attention_mask = torch.ones(encoder_hidden_shape, device=inputs_embeds.device)
encoder_extended_attention_mask = self.invert_attention_mask(encoder_attention_mask)
else:
encoder_extended_attention_mask = None
# Prepare head mask if needed
head_mask = self.get_head_mask(head_mask, self.config.num_layers)
cross_attn_head_mask = self.get_head_mask(cross_attn_head_mask, self.config.num_layers)
present_key_value_states = () if use_cache else None
all_hidden_states = () if output_hidden_states else None
all_attentions = () if output_attentions else None
all_cross_attentions = () if (output_attentions and self.is_decoder) else None
# Going through held blocks.
start_idx, end_idx = stage_index[0], stage_index[1]
for i in range(start_idx, end_idx):
past_key_value = past_key_values[i]
layer_module = self.block[i]
layer_head_mask = head_mask[i]
cross_attn_layer_head_mask = cross_attn_head_mask[i]
torch.cuda.set_device(hidden_states.device)
if self.gradient_checkpointing and self.training:
def create_custom_forward(module):
def custom_forward(*inputs):
return tuple(module(*inputs, use_cache, output_attentions))
return custom_forward
layer_outputs = checkpoint(
create_custom_forward(layer_module),
hidden_states,
extended_attention_mask,
position_bias,
encoder_hidden_states,
encoder_extended_attention_mask,
encoder_decoder_position_bias,
layer_head_mask,
cross_attn_layer_head_mask,
None, # past_key_value is always None with gradient checkpointing
)
else:
layer_outputs = layer_module(
hidden_states,
attention_mask=extended_attention_mask,
position_bias=position_bias,
encoder_hidden_states=encoder_hidden_states,
encoder_attention_mask=encoder_extended_attention_mask,
encoder_decoder_position_bias=encoder_decoder_position_bias,
layer_head_mask=layer_head_mask,
cross_attn_layer_head_mask=cross_attn_layer_head_mask,
past_key_value=past_key_value,
use_cache=use_cache,
output_attentions=output_attentions,
)
# layer_outputs is a tuple with:
# hidden-states, key-value-states, (self-attention position bias), (self-attention weights), (cross-attention position bias), (cross-attention weights)
if use_cache is False or use_cache is None:
layer_outputs = layer_outputs[:1] + (None,) + layer_outputs[1:]
hidden_states, present_key_value_state = layer_outputs[:2]
# We share the position biases between the layers - the first layer store them
# layer_outputs = hidden-states, key-value-states (self-attention position bias), (self-attention weights),
# (cross-attention position bias), (cross-attention weights)
position_bias = layer_outputs[2]
if in_decoder and encoder_hidden_states is not None:
encoder_decoder_position_bias = layer_outputs[4 if output_attentions else 3]
# append next layer key value states
if use_cache:
present_key_value_states = present_key_value_states + (present_key_value_state,)
# last layer
if at_last_stage:
hidden_states = self.final_layer_norm(hidden_states)
hidden_states = self.dropout(hidden_states)
if not return_dict:
return tuple(v for v in [
hidden_states,
present_key_value_states,
all_hidden_states,
all_attentions,
all_cross_attentions,
] if v is not None)
return BaseModelOutputWithPastAndCrossAttentions(
last_hidden_state=hidden_states,
past_key_values=present_key_value_states,
hidden_states=all_hidden_states,
attentions=all_attentions,
cross_attentions=all_cross_attentions,
)
else:
return {
'hidden_states': hidden_states,
'position_bias': position_bias,
'encoder_decoder_position_bias': encoder_decoder_position_bias
}
@staticmethod
def t5_model_forward(
self: T5Model,
input_ids: Optional[torch.LongTensor] = None,
attention_mask: Optional[torch.FloatTensor] = None,
decoder_input_ids: Optional[torch.LongTensor] = None,
decoder_attention_mask: Optional[torch.BoolTensor] = None,
head_mask: Optional[torch.FloatTensor] = None,
decoder_head_mask: Optional[torch.FloatTensor] = None,
cross_attn_head_mask: Optional[torch.Tensor] = None,
encoder_outputs: Optional[Tuple[Tuple[torch.FloatTensor]]] = None,
past_key_values: Optional[Tuple[Tuple[torch.FloatTensor]]] = None,
inputs_embeds: Optional[torch.Tensor] = None,
decoder_inputs_embeds: Optional[torch.Tensor] = None,
use_cache: Optional[bool] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
stage_manager: Optional[PipelineStageManager] = None,
hidden_states: Optional[torch.FloatTensor] = None,
position_bias: Optional[torch.Tensor] = None,
encoder_decoder_position_bias: Optional[torch.Tensor] = None,
stage_index: Optional[List[int]] = None,
decoder_starting_stage: Optional[int] = None,
) -> Union[Tuple[torch.FloatTensor], Seq2SeqModelOutput]:
# This function is modified on the basis of transformers.models.t5.modeling_t5.T5Model.forward.
# Please refer to original code of transformers for more details.
__HEAD_MASK_WARNING_MSG = """
The input argument `head_mask` was split into two arguments `head_mask` and `decoder_head_mask`. Currently,
`decoder_head_mask` is set to copy `head_mask`, but this feature is deprecated and will be removed in future versions.
If you do not want to use any `decoder_head_mask` now, please set `decoder_head_mask = torch.ones(num_layers,
num_heads)`.
"""
use_cache = use_cache if use_cache is not None else self.config.use_cache
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
logger = logging.get_logger(__name__)
# TODO: left the recording kv-value tensors as () or None type, this feature may be added in the future.
if past_key_values:
logger.warning_once('Non-empty past_key_values is not supported for pipeline models at the moment.')
past_key_values = None
if output_attentions:
logger.warning_once('output_attentions=True is not supported for pipeline models at the moment.')
output_attentions = False
if output_hidden_states:
logger.warning_once('output_hidden_states=True is not supported for pipeline models at the moment.')
output_hidden_states = False
if use_cache:
logger.warning_once('use_cache=True is not supported for pipeline models at the moment.')
use_cache = False
# FutureWarning: head_mask was separated into two input args - head_mask, decoder_head_mask
if head_mask is not None and decoder_head_mask is None:
if self.config.num_layers == self.config.num_decoder_layers:
warnings.warn(__HEAD_MASK_WARNING_MSG, FutureWarning)
decoder_head_mask = head_mask
in_decoder = stage_manager.stage >= decoder_starting_stage
# Stage is in encoder, directly return the output of t5_stack_forward
if not in_decoder:
encoder_outputs = T5PipelineForwards.t5_stack_forward(
self.encoder,
input_ids=input_ids,
attention_mask=attention_mask,
inputs_embeds=inputs_embeds,
head_mask=head_mask,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
stage_manager=stage_manager,
hidden_states=hidden_states,
position_bias=position_bias,
encoder_decoder_position_bias=encoder_decoder_position_bias,
stage_index=stage_index,
decoder_starting_stage=decoder_starting_stage)
if stage_manager.stage == decoder_starting_stage - 1:
# last stage of encoder
return {'encoder_outputs': encoder_outputs}
else:
return encoder_outputs
at_last_decoder_stage = stage_manager.is_last_stage()
at_first_decoder_stage = stage_manager.stage == decoder_starting_stage
if encoder_outputs is None:
raise ValueError("Non-empty encoder_outputs should be passed in at decoder stages.")
encoder_hidden_states = encoder_outputs[0]
if return_dict and not isinstance(encoder_outputs, BaseModelOutput):
encoder_outputs = BaseModelOutput(
last_hidden_state=encoder_outputs[0],
hidden_states=encoder_outputs[1] if len(encoder_outputs) > 1 else None,
attentions=encoder_outputs[2] if len(encoder_outputs) > 2 else None,
)
# Stage is in decoder, we assume that the outputs of last stage of encoder will be passed in.
if not at_first_decoder_stage and hidden_states is None:
raise ValueError("If not at the first layer of decoder, non-empty hidden_states must be provided.")
# Decode
decoder_outputs = T5PipelineForwards.t5_stack_forward(
self.decoder,
input_ids=decoder_input_ids,
attention_mask=decoder_attention_mask,
inputs_embeds=decoder_inputs_embeds,
past_key_values=past_key_values,
encoder_hidden_states=encoder_hidden_states,
encoder_attention_mask=attention_mask,
head_mask=decoder_head_mask,
cross_attn_head_mask=cross_attn_head_mask,
use_cache=use_cache,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
hidden_states=hidden_states,
position_bias=position_bias,
encoder_decoder_position_bias=encoder_decoder_position_bias,
stage_index=stage_index,
decoder_starting_stage=decoder_starting_stage)
# Directly return outputs of overloaded T5Stack forward if not at last stage.
if not at_last_decoder_stage:
decoder_outputs['encoder_outputs'] = encoder_outputs # encoder_outputs should be passed to the next stage
return decoder_outputs
if not return_dict:
return decoder_outputs + encoder_outputs
return Seq2SeqModelOutput(
last_hidden_state=decoder_outputs.last_hidden_state,
past_key_values=decoder_outputs.past_key_values,
decoder_hidden_states=decoder_outputs.hidden_states,
decoder_attentions=decoder_outputs.attentions,
cross_attentions=decoder_outputs.cross_attentions,
encoder_last_hidden_state=encoder_outputs.last_hidden_state,
encoder_hidden_states=encoder_outputs.hidden_states,
encoder_attentions=encoder_outputs.attentions,
)
@staticmethod
def t5_for_conditional_generation_forward(
self: T5ForConditionalGeneration,
input_ids: Optional[torch.LongTensor] = None,
attention_mask: Optional[torch.FloatTensor] = None,
decoder_input_ids: Optional[torch.LongTensor] = None,
decoder_attention_mask: Optional[torch.BoolTensor] = None,
head_mask: Optional[torch.FloatTensor] = None,
decoder_head_mask: Optional[torch.FloatTensor] = None,
cross_attn_head_mask: Optional[torch.Tensor] = None,
encoder_outputs: Optional[Tuple[Tuple[torch.Tensor]]] = None,
past_key_values: Optional[Tuple[Tuple[torch.Tensor]]] = None,
inputs_embeds: Optional[torch.FloatTensor] = None,
decoder_inputs_embeds: Optional[torch.FloatTensor] = None,
labels: Optional[torch.LongTensor] = None,
use_cache: Optional[bool] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
stage_manager: Optional[PipelineStageManager] = None,
hidden_states: Optional[torch.FloatTensor] = None,
position_bias: Optional[torch.Tensor] = None,
encoder_decoder_position_bias: Optional[torch.Tensor] = None,
stage_index: Optional[List[int]] = None,
decoder_starting_stage: Optional[int] = None,
) -> Union[Tuple[torch.FloatTensor], Seq2SeqLMOutput]:
# This function is modified on the basis of transformers.models.t5.modeling_t5.T5ForConditionalGeneration.forward.
# Please refer to original code of transformers for more details.
__HEAD_MASK_WARNING_MSG = """
The input argument `head_mask` was split into two arguments `head_mask` and `decoder_head_mask`. Currently,
`decoder_head_mask` is set to copy `head_mask`, but this feature is deprecated and will be removed in future versions.
If you do not want to use any `decoder_head_mask` now, please set `decoder_head_mask = torch.ones(num_layers,
num_heads)`.
"""
use_cache = use_cache if use_cache is not None else self.config.use_cache
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
logger = logging.get_logger(__name__)
# TODO: left the recording kv-value tensors as () or None type, this feature may be added in the future.
if past_key_values:
logger.warning_once('Non-empty past_key_values is not supported for pipeline models at the moment.')
past_key_values = None
if output_attentions:
logger.warning_once('output_attentions=True is not supported for pipeline models at the moment.')
output_attentions = False
if output_hidden_states:
logger.warning_once('output_hidden_states=True is not supported for pipeline models at the moment.')
output_hidden_states = False
if use_cache:
logger.warning_once('use_cache=True is not supported for pipeline models at the moment.')
use_cache = False
# FutureWarning: head_mask was separated into two input args - head_mask, decoder_head_mask
if head_mask is not None and decoder_head_mask is None:
if self.config.num_layers == self.config.num_decoder_layers:
warnings.warn(__HEAD_MASK_WARNING_MSG, FutureWarning)
decoder_head_mask = head_mask
in_decoder = stage_manager.stage >= decoder_starting_stage
# Stage is in encoder, directly return the output of t5_stack_forward
if not in_decoder:
encoder_outputs = T5PipelineForwards.t5_stack_forward(
self.encoder,
input_ids=input_ids,
attention_mask=attention_mask,
inputs_embeds=inputs_embeds,
head_mask=head_mask,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
stage_manager=stage_manager,
hidden_states=hidden_states,
position_bias=position_bias,
encoder_decoder_position_bias=encoder_decoder_position_bias,
stage_index=stage_index,
decoder_starting_stage=decoder_starting_stage)
if stage_manager.stage == decoder_starting_stage - 1:
# last stage of encoder
return {'encoder_outputs': encoder_outputs}
else:
return encoder_outputs
at_last_decoder_stage = stage_manager.is_last_stage()
at_first_decoder_stage = stage_manager.stage == decoder_starting_stage
if encoder_outputs is None:
raise ValueError("Non-empty encoder_outputs should be passed in at decoder stages.")
encoder_hidden_states = encoder_outputs[0]
if return_dict and not isinstance(encoder_outputs, BaseModelOutput):
encoder_outputs = BaseModelOutput(
last_hidden_state=encoder_outputs[0],
hidden_states=encoder_outputs[1] if len(encoder_outputs) > 1 else None,
attentions=encoder_outputs[2] if len(encoder_outputs) > 2 else None,
)
# Stage is in decoder, we assume that the outputs of last stage of encoder will be passed in.
if not at_first_decoder_stage and hidden_states is None:
raise ValueError("If not at the first layer of decoder, non-empty hidden_states must be provided.")
# Decode
decoder_outputs = T5PipelineForwards.t5_stack_forward(
self.decoder,
input_ids=decoder_input_ids,
attention_mask=decoder_attention_mask,
inputs_embeds=decoder_inputs_embeds,
past_key_values=past_key_values,
encoder_hidden_states=encoder_hidden_states,
encoder_attention_mask=attention_mask,
head_mask=decoder_head_mask,
cross_attn_head_mask=cross_attn_head_mask,
use_cache=use_cache,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
hidden_states=hidden_states,
position_bias=position_bias,
encoder_decoder_position_bias=encoder_decoder_position_bias,
stage_index=stage_index,
decoder_starting_stage=decoder_starting_stage)
# Directly return outputs of overloaded T5Stack forward if not at last stage.
if not at_last_decoder_stage:
decoder_outputs['encoder_outputs'] = encoder_outputs # encoder_outputs should be passed to the next stage
return decoder_outputs
sequence_output = decoder_outputs[0]
if self.config.tie_word_embeddings:
# Rescale output before projecting on vocab
# See https://github.com/tensorflow/mesh/blob/fa19d69eafc9a482aff0b59ddd96b025c0cb207d/mesh_tensorflow/transformer/transformer.py#L586
sequence_output = sequence_output * (self.model_dim**-0.5)
lm_logits = self.lm_head(sequence_output)
loss = None
if labels is not None:
loss_fct = CrossEntropyLoss(ignore_index=-100)
# move labels to correct device to enable PP
labels = labels.to(lm_logits.device)
loss = loss_fct(lm_logits.view(-1, lm_logits.size(-1)), labels.view(-1))
if not return_dict:
output = (lm_logits,) + decoder_outputs[1:] + encoder_outputs
return ((loss,) + output) if loss is not None else output
return Seq2SeqLMOutput(
loss=loss,
logits=lm_logits,
past_key_values=decoder_outputs.past_key_values,
decoder_hidden_states=decoder_outputs.hidden_states,
decoder_attentions=decoder_outputs.attentions,
cross_attentions=decoder_outputs.cross_attentions,
encoder_last_hidden_state=encoder_outputs.last_hidden_state,
encoder_hidden_states=encoder_outputs.hidden_states,
encoder_attentions=encoder_outputs.attentions,
)
@staticmethod
def t5_encoder_model_forward(
self: T5EncoderModel,
input_ids: Optional[torch.LongTensor] = None,
attention_mask: Optional[torch.FloatTensor] = None,
head_mask: Optional[torch.FloatTensor] = None,
inputs_embeds: Optional[torch.FloatTensor] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
stage_manager: Optional[PipelineStageManager] = None,
hidden_states: Optional[torch.FloatTensor] = None,
position_bias: Optional[torch.Tensor] = None,
encoder_decoder_position_bias: Optional[torch.Tensor] = None,
stage_index: Optional[List[int]] = None,
decoder_starting_stage: Optional[int] = None,
) -> Union[Tuple[torch.FloatTensor], BaseModelOutput]:
r"""
This function is modified on the basis of transformers.models.t5.modeling_gpt2.T5EncoderModel.forward.
Please refer to original code of transformers for more details.
```"""
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
outputs = T5PipelineForwards.t5_stack_forward(self.encoder,
input_ids=input_ids,
attention_mask=attention_mask,
inputs_embeds=inputs_embeds,
head_mask=head_mask,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
stage_manager=stage_manager,
hidden_states=hidden_states,
position_bias=position_bias,
encoder_decoder_position_bias=encoder_decoder_position_bias,
stage_index=stage_index,
decoder_starting_stage=decoder_starting_stage)
return outputs