import warnings from functools import partial from typing import Callable, Dict, List, Union import torch.nn as nn from torch import Tensor from torch.nn import Module from colossalai.shardformer.layer import FusedRMSNorm, Linear1D_Col, Linear1D_Row, RMSNorm, VocabParallelEmbedding1D from ..modeling.llama import ( LlamaPipelineForwards, get_llama_flash_attention_forward, get_lm_forward_with_dist_cross_entropy, ) from .base_policy import ModulePolicyDescription, Policy, SubModuleReplacementDescription __all__ = ["LlamaPolicy", "LlamaForCausalLMPolicy", "LlamaForSequenceClassificationPolicy"] class LlamaPolicy(Policy): def config_sanity_check(self): pass def preprocess(self): if self.shard_config.enable_tensor_parallelism: # Resize embedding vocab_size = self.model.config.vocab_size world_size = self.shard_config.tensor_parallel_size if vocab_size % world_size != 0: new_vocab_size = vocab_size + world_size - vocab_size % world_size self.model.resize_token_embeddings(new_vocab_size) return self.model def module_policy(self) -> Dict[Union[str, nn.Module], ModulePolicyDescription]: from transformers.models.llama.modeling_llama import LlamaAttention, LlamaDecoderLayer, LlamaModel policy = {} if self.shard_config.enable_fused_normalization: norm_cls = FusedRMSNorm else: norm_cls = RMSNorm if self.shard_config.enable_sequence_parallelism: self.shard_config.enable_sequence_parallelism = False warnings.warn("Llama dosen't support sequence parallelism now, will ignore the sequence parallelism flag.") if self.shard_config.enable_tensor_parallelism: decoder_attribute_replacement = { "self_attn.hidden_size": self.model.config.hidden_size // self.shard_config.tensor_parallel_size, "self_attn.num_heads": self.model.config.num_attention_heads // self.shard_config.tensor_parallel_size, } if getattr(self.model.config, "num_key_value_heads", False): decoder_attribute_replacement["self_attn.num_key_value_heads"] = ( self.model.config.num_key_value_heads // self.shard_config.tensor_parallel_size ) policy[LlamaDecoderLayer] = ModulePolicyDescription( attribute_replacement=decoder_attribute_replacement, sub_module_replacement=[ SubModuleReplacementDescription( suffix="self_attn.q_proj", target_module=Linear1D_Col, ), SubModuleReplacementDescription( suffix="self_attn.k_proj", target_module=Linear1D_Col, ), SubModuleReplacementDescription( suffix="self_attn.v_proj", target_module=Linear1D_Col, ), SubModuleReplacementDescription( suffix="self_attn.o_proj", target_module=Linear1D_Row, ), SubModuleReplacementDescription( suffix="mlp.gate_proj", target_module=Linear1D_Col, ), SubModuleReplacementDescription( suffix="mlp.up_proj", target_module=Linear1D_Col, ), SubModuleReplacementDescription( suffix="mlp.down_proj", target_module=Linear1D_Row, ), ], ) self.append_or_create_submodule_replacement( description=SubModuleReplacementDescription( suffix="embed_tokens", target_module=VocabParallelEmbedding1D, ), policy=policy, target_key=LlamaModel, ) # optimization configuration self.append_or_create_submodule_replacement( description=[ SubModuleReplacementDescription( suffix="input_layernorm", target_module=norm_cls, ), SubModuleReplacementDescription( suffix="post_attention_layernorm", target_module=norm_cls, ), ], policy=policy, target_key=LlamaDecoderLayer, ) self.append_or_create_submodule_replacement( description=SubModuleReplacementDescription( suffix="norm", target_module=norm_cls, ), policy=policy, target_key=LlamaModel, ) # use flash attention if self.shard_config.enable_flash_attention: self.append_or_create_method_replacement( description={ "forward": get_llama_flash_attention_forward(), }, policy=policy, target_key=LlamaAttention, ) return policy def postprocess(self): return self.model def set_pipeline_forward(self, model_cls: nn.Module, new_forward: Callable, policy: Dict) -> None: """If under pipeline parallel setting, replacing the original forward method of huggingface to customized forward method, and add this changing to policy.""" if self.pipeline_stage_manager is None: return stage_manager = self.pipeline_stage_manager if self.model.__class__.__name__ == "LlamaModel": module = self.model else: module = self.model.model if stage_manager.is_interleave: layers_per_stage = self.distribute_layers( len(module.layers), stage_manager.num_stages * stage_manager.num_model_chunks ) stage_manager.stage_indices = Policy.get_stage_index( layers_per_stage, stage_manager.stage, num_model_chunks=stage_manager.num_model_chunks, num_stages=stage_manager.num_stages, ) method_replacement = { "forward": partial(new_forward, stage_manager=stage_manager, shard_config=self.shard_config) } else: layers_per_stage = Policy.distribute_layers(len(module.layers), stage_manager.num_stages) stage_index = Policy.get_stage_index(layers_per_stage, stage_manager.stage) method_replacement = { "forward": partial( new_forward, stage_manager=stage_manager, stage_index=stage_index, shard_config=self.shard_config ) } self.append_or_create_method_replacement( description=method_replacement, policy=policy, target_key=model_cls ) self.append_or_create_method_replacement(description=method_replacement, policy=policy, target_key=model_cls) def get_held_layers(self) -> List[Module]: """Get pipeline layers for current stage.""" assert self.pipeline_stage_manager is not None if self.model.__class__.__name__ == "LlamaModel": module = self.model else: module = self.model.model stage_manager = self.pipeline_stage_manager held_layers = [] if stage_manager.is_interleave: assert stage_manager.num_model_chunks is not None layers_per_stage = self.distribute_layers( len(module.layers), stage_manager.num_stages * stage_manager.num_model_chunks ) stage_indices = Policy.get_stage_index( layers_per_stage, stage_manager.stage, num_model_chunks=stage_manager.num_model_chunks, num_stages=stage_manager.num_stages, ) if stage_manager.is_first_stage(ignore_chunk=True): held_layers.append(module.embed_tokens) for start_idx, end_idx in stage_indices: held_layers.extend(module.layers[start_idx:end_idx]) if stage_manager.is_last_stage(ignore_chunk=True): held_layers.append(module.norm) else: layers_per_stage = self.distribute_layers(len(module.layers), stage_manager.num_stages) if stage_manager.is_first_stage(): held_layers.append(module.embed_tokens) start_idx, end_idx = self.get_stage_index(layers_per_stage, stage_manager.stage) held_layers.extend(module.layers[start_idx:end_idx]) if stage_manager.is_last_stage(): held_layers.append(module.norm) return held_layers class LlamaModelPolicy(LlamaPolicy): def module_policy(self): policy = super().module_policy() from transformers.models.llama.modeling_llama import LlamaModel if self.pipeline_stage_manager: # set None as default self.set_pipeline_forward( model_cls=LlamaModel, new_forward=LlamaPipelineForwards.llama_model_forward, policy=policy ) return policy def get_held_layers(self) -> List[Module]: """Get pipeline layers for current stage.""" held_layers = super().get_held_layers() return held_layers def get_shared_params(self) -> List[Dict[int, Tensor]]: """No shared params in llama model""" return [] class LlamaForCausalLMPolicy(LlamaPolicy): def module_policy(self): from transformers import LlamaForCausalLM policy = super().module_policy() if self.shard_config.enable_tensor_parallelism: # add a new item for casual lm new_item = { LlamaForCausalLM: ModulePolicyDescription( sub_module_replacement=[ SubModuleReplacementDescription(suffix="lm_head", target_module=Linear1D_Col) ], method_replacement={"forward": get_lm_forward_with_dist_cross_entropy(self.shard_config)}, ) } policy.update(new_item) if self.pipeline_stage_manager: # set None as default self.set_pipeline_forward( model_cls=LlamaForCausalLM, new_forward=LlamaPipelineForwards.llama_for_causal_lm_forward, policy=policy ) return policy def get_held_layers(self) -> List[Module]: """Get pipeline layers for current stage.""" stage_manager = self.pipeline_stage_manager held_layers = super().get_held_layers() if stage_manager.is_last_stage(ignore_chunk=True): held_layers.append(self.model.lm_head) return held_layers def get_shared_params(self) -> List[Dict[int, Tensor]]: llama_model = self.model.model if self.pipeline_stage_manager and self.pipeline_stage_manager.num_stages > 1: if ( id(llama_model.embed_tokens.weight) == id(self.model.lm_head.weight) and self.pipeline_stage_manager.num_stages > 1 ): # tie weights return [ { 0: llama_model.embed_tokens.weight, self.pipeline_stage_manager.num_stages - 1: self.model.lm_head.weight, } ] return [] class LlamaForSequenceClassificationPolicy(LlamaPolicy): def module_policy(self): from transformers import LlamaForSequenceClassification policy = super().module_policy() if self.shard_config.enable_tensor_parallelism: # add a new item for sequence classification new_item = { LlamaForSequenceClassification: ModulePolicyDescription( sub_module_replacement=[ SubModuleReplacementDescription( suffix="score", target_module=Linear1D_Col, kwargs=dict(gather_output=True) ) ] ) } policy.update(new_item) # to be confirmed if self.pipeline_stage_manager: # set None as default self.set_pipeline_forward( model_cls=LlamaForSequenceClassification, new_forward=LlamaPipelineForwards.llama_for_sequence_classification_forward, policy=policy, ) return policy def get_held_layers(self) -> List[Module]: """Get pipeline layers for current stage.""" stage_manager = self.pipeline_stage_manager held_layers = super().get_held_layers() if stage_manager.is_last_stage(ignore_chunk=True): held_layers.append(self.model.score) return held_layers def get_shared_params(self) -> List[Dict[int, Tensor]]: """No shared params in llama for sequence classification model""" return []