[Feature] Split cross-entropy computation in SP (#5959)

* halfway

* fix cross-PP-stage position id length diff bug

* fix typo

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* unified cross entropy func for all shardformer models

* remove redundant lines

* add basic ring attn; debug cross entropy

* fwd bwd logic complete

* fwd bwd logic complete; add experimental triton rescale

* precision tests passed

* precision tests passed

* fix typos and remove misc files

* update softmax_lse shape by new interface

* change tester name

* remove buffer clone; support packed seq layout

* add varlen tests

* fix typo

* all tests passed

* add dkv_group; fix mask

* remove debug statements

* adapt chatglm, command-R, qwen

* debug

* halfway

* fix cross-PP-stage position id length diff bug

* fix typo

* fix typo

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* unified cross entropy func for all shardformer models

* remove redundant lines

* add basic ring attn; debug cross entropy

* fwd bwd logic complete

* fwd bwd logic complete; add experimental triton rescale

* precision tests passed

* precision tests passed

* fix typos and remove misc files

* add sp_mode to benchmark; fix varlen interface

* update softmax_lse shape by new interface

* add varlen tests

* fix typo

* all tests passed

* add dkv_group; fix mask

* remove debug statements

* add comments

* q1 index only once

* remove events to simplify stream sync

* simplify forward/backward logic

* 2d ring forward passed

* 2d ring backward passed

* fixes

* fix ring attn loss

* 2D ring backward + llama passed

* merge

* update logger

* fix typo

* rebase

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* fix typo

* remove typos

* fixes

* support GPT

---------

Co-authored-by: Edenzzzz <wtan45@wisc.edu>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
This commit is contained in:
Wenxuan Tan
2024-09-10 12:06:50 +08:00
committed by GitHub
parent b3db1058ec
commit 8fd25d6e09
25 changed files with 527 additions and 1173 deletions

View File

@@ -25,7 +25,6 @@ from transformers.models.llama.modeling_llama import (
from transformers.utils import logging
from colossalai.pipeline.stage_manager import PipelineStageManager
from colossalai.shardformer.layer import AttnMaskType
from colossalai.shardformer.layer._operation import all_to_all_comm, gather_sp_output, split_forward_gather_backward
from colossalai.shardformer.layer.utils import is_share_sp_tp, split_batch_zigzag
from colossalai.shardformer.shard import ShardConfig
@@ -58,10 +57,7 @@ class LlamaPipelineForwards:
hidden_states: Optional[torch.FloatTensor] = None,
stage_index: Optional[List[int]] = None,
shard_config: ShardConfig = None,
# Split output only when computing cross entropy using llama_for_causal_lm_forward
# or get_lm_forward_with_dist_cross_entropy
# Default to True to avoid bug when calling classification forward from huggingface
force_sp_output_gather: bool = True,
force_sp_gather: bool = True, # Set to false only when computing cross entropy
):
logger = logging.get_logger(__name__)
@@ -78,8 +74,9 @@ class LlamaPipelineForwards:
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
disable_pp = stage_manager is None
# retrieve input_ids and inputs_embeds
if stage_manager.is_first_stage():
if disable_pp or stage_manager.is_first_stage():
if input_ids is not None and inputs_embeds is not None:
raise ValueError("You cannot specify both input_ids and inputs_embeds at the same time")
elif input_ids is not None:
@@ -88,10 +85,10 @@ class LlamaPipelineForwards:
batch_size, seq_length, _ = inputs_embeds.shape[:2]
else:
raise ValueError("You have to specify either input_ids or inputs_embeds")
device = input_ids.device if input_ids is not None else inputs_embeds.device
if inputs_embeds is None:
inputs_embeds = self.embed_tokens(input_ids)
hidden_states = inputs_embeds
device = hidden_states.device
else:
input_shape = hidden_states.shape[:-1]
batch_size, seq_length = input_shape
@@ -101,8 +98,8 @@ class LlamaPipelineForwards:
sp_mode = shard_config.sequence_parallelism_mode
sp_group = shard_config.sequence_parallel_process_group
sp_size = shard_config.sequence_parallel_size
if sp_mode == "all_to_all" and not stage_manager.is_first_stage():
# For generating full positions ids, as the states will be gather along the seq dim in the attention layer later.
# Generating full positions ids for modes that gather sequence before attn
if stage_manager and (sp_mode != "ring_attn" and not stage_manager.is_first_stage()):
seq_length *= sp_size
past_seen_tokens = 0
@@ -117,7 +114,6 @@ class LlamaPipelineForwards:
seq_length_with_past = seq_length + past_seen_tokens
# TODO(jianghai): left the recording kv-value tensors as () or None type, this feature may be added in the future.
if output_attentions:
logger.warning_once("output_attentions=True is not supported for pipeline models at the moment.")
output_attentions = False
@@ -130,14 +126,13 @@ class LlamaPipelineForwards:
if position_ids is None:
position_ids = cache_position.unsqueeze(0)
# embed positions, for the first stage, hidden_states is the input embeddings,
# for the other stages, hidden_states is the output of the previous stage
if not stage_manager.is_first_stage() and sp_mode == "ring_attn":
no_split_input = disable_pp or not stage_manager.is_first_stage()
if no_split_input and sp_mode == "ring_attn":
_, attn_kwargs, _ = RingAttention.prepare_varlen_batch(attention_mask, sp_group)
elif shard_config.enable_flash_attention:
# in this case, attention_mask is a dict rather than a tensor
mask_shape = (batch_size, 1, seq_length_with_past, seq_length_with_past)
attn_kwargs = ColoAttention.prepare_attn_kwargs(
attn_kwargs: dict = ColoAttention.prepare_attn_kwargs(
mask_shape,
hidden_states.dtype,
hidden_states.device,
@@ -146,15 +141,15 @@ class LlamaPipelineForwards:
invert=(sp_mode != "ring_attn"),
)
else:
attn_kwargs = self._update_causal_mask(attention_mask, hidden_states, cache_position)
attn_kwargs: torch.Tensor = self._update_causal_mask(attention_mask, hidden_states, cache_position)
# Support SP + PP
# TODO: support padded casual cu_seqlens across stages
if stage_manager.is_first_stage():
# Support SP + PP. Later stages have already received the split input.
split_input = disable_pp or stage_manager.is_first_stage()
if split_input:
# Ring Attention zigzag batch processing
if sp_mode == "ring_attn":
assert shard_config.enable_flash_attention, "Ring Attention inherently requires Flash Attention."
if attn_kwargs["attention_mask_type"] == AttnMaskType.PADDED_CAUSAL:
if not attention_mask.bool().all():
hidden_states, attn_kwargs, position_ids = RingAttention.prepare_varlen_batch(
attention_mask, sp_group, hidden_states, position_ids
)
@@ -181,8 +176,8 @@ class LlamaPipelineForwards:
all_hidden_states = () if output_hidden_states else None
all_self_attns = () if output_attentions else None
next_decoder_cache = None
start_idx, end_idx = (0, len(self.layers)) if disable_pp else (stage_index[0], stage_index[1])
start_idx, end_idx = stage_index[0], stage_index[1]
num_ckpt_layers = 0
if self.gradient_checkpointing and self.training:
num_ckpt_layers = end_idx - start_idx
@@ -228,18 +223,16 @@ class LlamaPipelineForwards:
if output_attentions:
all_self_attns += (layer_outputs[1],)
if stage_manager.is_last_stage():
if disable_pp or stage_manager.is_last_stage():
hidden_states = self.norm(hidden_states)
if (not shard_config.parallel_output) or force_sp_output_gather or is_share_sp_tp(sp_mode):
hidden_states = gather_sp_output(
hidden_states, sp_group, sp_mode, fp8_communication=shard_config.fp8_communication
)
if (not shard_config.parallel_output) or force_sp_gather or is_share_sp_tp(sp_mode): # noqa
hidden_states = gather_sp_output(hidden_states, shard_config)
# add hidden states from the last decoder layer
if output_hidden_states:
all_hidden_states += (hidden_states,)
next_cache = next_decoder_cache if use_cache else None
if stage_manager.is_last_stage():
if disable_pp or stage_manager.is_last_stage():
if not return_dict:
return tuple(
v
@@ -257,7 +250,7 @@ class LlamaPipelineForwards:
hidden_states=all_hidden_states,
attentions=all_self_attns,
)
# always return dict for imediate stage
# always return dict for intermediate stage
return {"hidden_states": hidden_states}
@staticmethod
@@ -323,7 +316,7 @@ class LlamaPipelineForwards:
# Split labels in a zigzag fashion too
sp_group = shard_config.sequence_parallel_process_group
if attention_mask.bool().all():
labels = split_batch_zigzag(labels, sp_group, seq_dim=1)
labels = split_batch_zigzag(labels, sp_group, seq_dim=1, is_label=True)
else:
# [B, max_seqlen // sp_size]
labels, _, _ = RingAttention.prepare_varlen_batch(attention_mask, sp_group, labels, is_label=True)
@@ -345,16 +338,17 @@ class LlamaPipelineForwards:
hidden_states=hidden_states,
stage_index=stage_index,
shard_config=shard_config,
force_sp_output_gather=False,
force_sp_gather=False,
)
past_key_values = None
if stage_manager.is_last_stage():
disable_pp = stage_manager is None
if disable_pp or stage_manager.is_last_stage():
hidden_states = outputs[0]
logits = self.lm_head(hidden_states)
loss = dist_cross_entropy(
labels, logits, shard_config, self.lm_head.out_features, self.config.vocab_size, self.model.dtype
)
loss = None
if labels is not None:
loss = dist_cross_entropy(labels, logits, shard_config, self.lm_head.out_features, self.model.dtype)
if not return_dict:
output = (logits,) + outputs[1:]
@@ -629,263 +623,3 @@ def get_llama_flash_attention_forward(shard_config: ShardConfig, sp_mode=None, s
return attn_output, attn_weights, past_key_value
return forward
def get_llama_flash_attention_model_forward(shard_config: ShardConfig, sp_mode=None, sp_size=None, sp_group=None):
logger = logging.get_logger(__name__)
def forward(
self,
input_ids: torch.LongTensor = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.LongTensor] = None,
past_key_values: Optional[List[torch.FloatTensor]] = None,
inputs_embeds: Optional[torch.FloatTensor] = None,
use_cache: Optional[bool] = None,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
cache_position: Optional[torch.LongTensor] = None,
# Split output only when computing cross entropy using llama_for_causal_lm_forward
# or get_lm_forward_with_dist_cross_entropy
# Default to True to avoid bug when calling classification forward from huggingface
force_sp_output_gather: bool = True,
) -> Union[Tuple, BaseModelOutputWithPast]:
output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
output_hidden_states = (
output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
)
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
# retrieve input_ids and inputs_embeds
if (input_ids is None) ^ (inputs_embeds is not None):
raise ValueError(
"You cannot specify both input_ids and inputs_embeds at the same time, and must specify either one"
)
if (self.gradient_checkpointing or sp_mode in ["ring", "all_to_all"]) and self.training:
if use_cache:
logger.warning_once(
"`use_cache=True` is incompatible with gradient checkpointing. Setting `use_cache=False`..."
)
use_cache = False
if inputs_embeds is None:
inputs_embeds = self.embed_tokens(input_ids)
past_seen_tokens = 0
seq_len = inputs_embeds.shape[1]
batch_size = inputs_embeds.shape[0]
if use_cache: # kept for BC (cache positions)
if not isinstance(past_key_values, StaticCache):
past_key_values = DynamicCache.from_legacy_cache(past_key_values)
past_seen_tokens = past_key_values.get_seq_length()
if cache_position is None:
if isinstance(past_key_values, StaticCache):
raise ValueError("cache_position is a required argument when using StaticCache.")
cache_position = torch.arange(past_seen_tokens, past_seen_tokens + seq_len, device=inputs_embeds.device)
if position_ids is None:
position_ids = cache_position.unsqueeze(0)
if shard_config.enable_flash_attention:
mask_shape = (batch_size, 1, seq_len, past_seen_tokens + seq_len)
attn_kwargs: dict = ColoAttention.prepare_attn_kwargs(
mask_shape,
inputs_embeds.dtype,
inputs_embeds.device,
q_padding_mask=attention_mask,
is_causal=True,
invert=(sp_mode != "ring_attn"),
)
else:
attn_kwargs: torch.Tensor = self._update_causal_mask(attention_mask, inputs_embeds, cache_position)
# Ring Attention zigzag batch processing
if sp_mode == "ring_attn":
assert shard_config.enable_flash_attention, "Ring Attention inherently requires Flash Attention."
if attn_kwargs["attention_mask_type"] == AttnMaskType.PADDED_CAUSAL:
inputs_embeds, attn_kwargs, position_ids = RingAttention.prepare_varlen_batch(
attention_mask, sp_group, inputs_embeds, position_ids
)
else:
inputs_embeds, position_ids = split_batch_zigzag([inputs_embeds, position_ids], sp_group)
attn_kwargs = {"attention_mask_type": attn_kwargs["attention_mask_type"]} # drop redundant tensors
elif is_share_sp_tp(sp_mode):
inputs_embeds = split_forward_gather_backward(
inputs_embeds, 1, sp_group, fp8_communication=shard_config.fp8_communication
)
elif sp_mode == "all_to_all":
inputs_embeds = split_forward_gather_backward(
inputs_embeds, 1, sp_group, 1 / sp_size, fp8_communication=shard_config.fp8_communication
)
hidden_states = inputs_embeds
# decoder layers
all_hidden_states = () if output_hidden_states else None
all_self_attns = () if output_attentions else None
next_decoder_cache = None
for decoder_layer in self.layers:
if output_hidden_states:
all_hidden_states += (hidden_states,)
if self.gradient_checkpointing and self.training:
layer_outputs = self._gradient_checkpointing_func(
decoder_layer.__call__,
hidden_states,
attn_kwargs,
position_ids,
past_key_values,
output_attentions,
use_cache,
cache_position,
)
else:
layer_outputs = decoder_layer(
hidden_states,
attention_mask=attn_kwargs,
position_ids=position_ids,
past_key_value=past_key_values,
output_attentions=output_attentions,
use_cache=use_cache,
cache_position=cache_position,
)
hidden_states = layer_outputs[0]
if use_cache:
next_decoder_cache = layer_outputs[2 if output_attentions else 1]
if output_attentions:
all_self_attns += (layer_outputs[1],)
hidden_states = self.norm(hidden_states)
# Cases that don't support parallelizing cross entropy computation along sequence
if (not shard_config.parallel_output) or is_share_sp_tp(sp_mode) or force_sp_output_gather:
hidden_states = gather_sp_output(
hidden_states, sp_group, sp_mode, fp8_communication=shard_config.fp8_communication
)
# add hidden states from the last decoder layer
if output_hidden_states:
all_hidden_states += (hidden_states,)
next_cache = None
if use_cache:
next_cache = (
next_decoder_cache.to_legacy_cache() if isinstance(next_decoder_cache, Cache) else next_decoder_cache
)
if not return_dict:
return tuple(v for v in [hidden_states, next_cache, all_hidden_states, all_self_attns] if v is not None)
return BaseModelOutputWithPast(
last_hidden_state=hidden_states,
past_key_values=next_cache,
hidden_states=all_hidden_states,
attentions=all_self_attns,
)
return forward
def get_lm_forward_with_dist_cross_entropy(shard_config: ShardConfig):
from transformers import LlamaForCausalLM
def forward(
self: LlamaForCausalLM,
input_ids: torch.LongTensor = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.LongTensor] = None,
past_key_values: Optional[List[torch.FloatTensor]] = None,
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,
cache_position: Optional[torch.LongTensor] = None,
) -> Union[Tuple, CausalLMOutputWithPast]:
r"""
Args:
labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
Labels for computing the masked language modeling loss. Indices should either be in `[0, ...,
config.vocab_size]` or -100 (see `input_ids` docstring). Tokens with indices set to `-100` are ignored
(masked), the loss is only computed for the tokens with labels in `[0, ..., config.vocab_size]`.
Returns:
Example:
```python
>>> from transformers import AutoTokenizer, LlamaForCausalLM
>>> model = LlamaForCausalLM.from_pretrained(PATH_TO_CONVERTED_WEIGHTS)
>>> tokenizer = AutoTokenizer.from_pretrained(PATH_TO_CONVERTED_TOKENIZER)
>>> prompt = "Hey, are you conscious? Can you talk to me?"
>>> inputs = tokenizer(prompt, return_tensors="pt")
>>> # Generate
>>> generate_ids = model.generate(inputs.input_ids, max_length=30)
>>> tokenizer.batch_decode(generate_ids, skip_special_tokens=True, clean_up_tokenization_spaces=False)[0]
"Hey, are you conscious? Can you talk to me?\nI'm not conscious, but I can talk to you."
```"""
output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
output_hidden_states = (
output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
)
return_dict = return_dict if return_dict is not None else self.config.use_return_dict
if shard_config.sequence_parallelism_mode == "ring_attn" and shard_config.parallel_output:
# Special processing: Split labels in a zigzag fashion too
sp_group = shard_config.sequence_parallel_process_group
if attention_mask.bool().all():
labels = split_batch_zigzag(labels, sp_group, seq_dim=1, is_label=True)
else:
# [B, max_seq_len // sp_size]
labels, _, _ = RingAttention.prepare_varlen_batch(attention_mask, sp_group, labels, is_label=True)
# decoder outputs consists of (dec_features, layer_state, dec_hidden, dec_attn)
outputs = self.model(
input_ids=input_ids,
attention_mask=attention_mask,
position_ids=position_ids,
past_key_values=past_key_values,
inputs_embeds=inputs_embeds,
use_cache=use_cache,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
cache_position=cache_position,
force_sp_output_gather=False,
)
hidden_states = outputs[0]
if self.config.pretraining_tp > 1:
lm_head_slices = self.lm_head.weight.split(self.vocab_size // self.config.pretraining_tp, dim=0)
logits = [F.linear(hidden_states, lm_head_slices[i]) for i in range(self.config.pretraining_tp)]
logits = torch.cat(logits, dim=-1)
else:
logits = self.lm_head(hidden_states)
logits = logits.float()
loss = dist_cross_entropy(
labels, logits, shard_config, self.lm_head.out_features, self.config.vocab_size, self.model.dtype
)
if not return_dict:
output = (logits,) + outputs[1:]
return (loss,) + output if loss is not None else output
return CausalLMOutputWithPast(
loss=loss,
logits=logits,
past_key_values=outputs.past_key_values,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
return forward