276 lines
11 KiB
Python

# SPDX-License-Identifier: Apache-2.0
"""PyTorch MAMBA model."""
from typing import Iterable, Optional, Set, Tuple
import torch
from torch import nn
from transformers import MambaConfig
from vllm.config import CacheConfig, VllmConfig
from vllm.distributed import get_tensor_model_parallel_world_size
from vllm.distributed.parallel_state import get_pp_group
from vllm.model_executor.layers.layernorm import RMSNorm
from vllm.model_executor.layers.logits_processor import LogitsProcessor
from vllm.model_executor.layers.mamba.mamba_mixer import MambaMixer
from vllm.model_executor.layers.quantization.base_config import (
QuantizationConfig)
from vllm.model_executor.layers.sampler import SamplerOutput, get_sampler
from vllm.model_executor.layers.vocab_parallel_embedding import (
DEFAULT_VOCAB_PADDING_SIZE, ParallelLMHead, VocabParallelEmbedding)
from vllm.model_executor.model_loader.weight_utils import default_weight_loader
from vllm.model_executor.models.interfaces import (HasInnerState,
IsAttentionFree, SupportsPP)
from vllm.model_executor.models.mamba_cache import (MambaCacheManager,
MambaCacheParams)
from vllm.model_executor.sampling_metadata import SamplingMetadata
from vllm.sequence import IntermediateTensors
from vllm.utils import LayerBlockType
from .utils import (is_pp_missing_parameter,
make_empty_intermediate_tensors_factory, make_layers,
maybe_prefix)
KVCache = Tuple[torch.Tensor, torch.Tensor]
class MambaDecoderLayer(nn.Module):
def __init__(self,
config: MambaConfig,
cache_config: Optional[CacheConfig] = None,
quant_config: Optional[QuantizationConfig] = None,
is_lora_enabled: Optional[bool] = False) -> None:
super().__init__()
self.config = config
self.is_falcon_mamba = config.model_type == "falcon_mamba"
self.is_lora_enabled = is_lora_enabled
mixer_rms_eps = config.mixer_rms_eps if self.is_falcon_mamba else None
self.mixer = MambaMixer(hidden_size=config.hidden_size,
ssm_state_size=config.state_size,
conv_kernel_size=config.conv_kernel,
intermediate_size=config.intermediate_size,
time_step_rank=config.time_step_rank,
use_conv_bias=config.use_conv_bias,
use_bias=config.use_bias,
use_rms_norm=self.is_falcon_mamba,
rms_norm_has_weight=not self.is_falcon_mamba,
rms_norm_eps=mixer_rms_eps,
activation=config.hidden_act,
is_lora_enabled=self.is_lora_enabled)
self.norm = RMSNorm(config.hidden_size, eps=config.layer_norm_epsilon)
def forward(
self,
hidden_states: torch.Tensor,
residual: Optional[torch.Tensor],
mamba_cache_params: MambaCacheParams,
**kwargs,
):
if residual is None:
residual = hidden_states
hidden_states = self.norm(hidden_states)
else:
hidden_states, residual = self.norm(hidden_states, residual)
hidden_states = self.mixer(hidden_states, mamba_cache_params)
return hidden_states, residual
class MambaModel(nn.Module):
def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""):
super().__init__()
config = vllm_config.model_config.hf_config
cache_config = vllm_config.cache_config
quant_config = vllm_config.quant_config
lora_config = vllm_config.lora_config
is_lora_enabled = bool(lora_config)
self.config = config
self.padding_idx = config.pad_token_id
lora_vocab = ((lora_config.lora_extra_vocab_size *
(lora_config.max_loras or 1)) if lora_config else 0)
self.vocab_size = config.vocab_size + lora_vocab
self.org_vocab_size = config.vocab_size
self.embeddings = VocabParallelEmbedding(
self.vocab_size,
config.hidden_size,
org_num_embeddings=config.vocab_size,
)
self.start_layer, self.end_layer, self.layers = make_layers(
config.num_hidden_layers,
lambda prefix: MambaDecoderLayer(config,
cache_config=cache_config,
quant_config=quant_config,
is_lora_enabled=is_lora_enabled),
prefix=f"{prefix}.layers")
self.norm_f = RMSNorm(config.hidden_size,
eps=config.layer_norm_epsilon)
self.make_empty_intermediate_tensors = (
make_empty_intermediate_tensors_factory(
["hidden_states", "residual"], config.hidden_size))
def get_input_embeddings(self, input_ids: torch.Tensor) -> torch.Tensor:
return self.embeddings(input_ids)
def forward(
self,
input_ids: torch.Tensor,
positions: torch.Tensor,
mamba_cache_params: MambaCacheParams,
intermediate_tensors: Optional[IntermediateTensors] = None,
inputs_embeds: Optional[torch.Tensor] = None,
) -> torch.Tensor:
if get_pp_group().is_first_rank:
if inputs_embeds is not None:
hidden_states = inputs_embeds
else:
hidden_states = self.get_input_embeddings(input_ids)
residual = None
else:
assert intermediate_tensors is not None
hidden_states = intermediate_tensors["hidden_states"]
residual = intermediate_tensors["residual"]
for i in range(self.start_layer, self.end_layer):
layer = self.layers[i]
hidden_states, residual = layer(
positions=positions,
hidden_states=hidden_states,
residual=residual,
mamba_cache_params=mamba_cache_params.at_layer_idx(
i - self.start_layer))
if not get_pp_group().is_last_rank:
return IntermediateTensors({
"hidden_states": hidden_states,
"residual": residual
})
hidden_states, _ = self.norm_f(hidden_states, residual)
return hidden_states
class MambaForCausalLM(nn.Module, HasInnerState, IsAttentionFree, SupportsPP):
def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""):
config = vllm_config.model_config.hf_config
cache_config = vllm_config.cache_config
lora_config = vllm_config.lora_config
self.scheduler_config = vllm_config.scheduler_config
assert not cache_config.enable_prefix_caching, \
"Mamba does not support prefix caching"
super().__init__()
self.config = config
self.vllm_config = vllm_config
self.model_config = vllm_config.model_config
self.backbone = MambaModel(vllm_config=vllm_config,
prefix=maybe_prefix(prefix, "backbone"))
self.unpadded_vocab_size = config.vocab_size
if lora_config:
self.unpadded_vocab_size += lora_config.lora_extra_vocab_size
if config.tie_word_embeddings:
self.lm_head = self.backbone.embeddings
else:
self.lm_head = ParallelLMHead(
self.unpadded_vocab_size,
config.hidden_size,
org_num_embeddings=config.vocab_size,
padding_size=DEFAULT_VOCAB_PADDING_SIZE
# We need bigger padding if using lora for kernel
# compatibility
if not lora_config else lora_config.lora_vocab_padding_size,
)
# Used to track and store by the Mamba cache between steps.
self.mamba_cache: Optional[MambaCacheManager] = None
self.logits_processor = LogitsProcessor(self.unpadded_vocab_size,
config.vocab_size)
self.sampler = get_sampler()
self.make_empty_intermediate_tensors = (
self.backbone.make_empty_intermediate_tensors)
def get_input_embeddings(self, input_ids: torch.Tensor) -> torch.Tensor:
return self.backbone.get_input_embeddings(input_ids)
def forward(self,
input_ids: torch.Tensor,
positions: torch.Tensor,
intermediate_tensors: Optional[IntermediateTensors] = None,
inputs_embeds: Optional[torch.Tensor] = None,
**kwargs):
if self.mamba_cache is None:
num_mamba_layers = self.model_config.get_num_layers_by_block_type(
self.vllm_config.parallel_config, LayerBlockType.mamba)
self.mamba_cache = MambaCacheManager(
self.vllm_config, self.lm_head.weight.dtype, num_mamba_layers,
*self._get_mamba_cache_shape())
mamba_cache_params = self.mamba_cache.current_run_tensors(**kwargs)
hidden_states = self.backbone(input_ids, positions, mamba_cache_params,
intermediate_tensors, inputs_embeds)
return hidden_states
def copy_inputs_before_cuda_graphs(self, input_buffers, **kwargs):
return self.mamba_cache.copy_inputs_before_cuda_graphs(
input_buffers, **kwargs)
def get_seqlen_agnostic_capture_inputs(self, batch_size: int):
return self.mamba_cache.get_seqlen_agnostic_capture_inputs(batch_size)
def _get_mamba_cache_shape(
self) -> Tuple[Tuple[int, int], Tuple[int, int]]:
world_size = get_tensor_model_parallel_world_size()
conv_state_shape = (
self.config.intermediate_size // world_size,
self.config.conv_kernel - 1,
)
temporal_state_shape = (
self.config.intermediate_size // world_size,
self.config.state_size,
)
return conv_state_shape, temporal_state_shape
def compute_logits(self, hidden_states: torch.Tensor,
sampling_metadata: SamplingMetadata) -> torch.Tensor:
logits = self.logits_processor(self.lm_head, hidden_states,
sampling_metadata)
return logits
def sample(
self,
logits: Optional[torch.Tensor],
sampling_metadata: SamplingMetadata,
) -> Optional[SamplerOutput]:
next_tokens = self.sampler(logits, sampling_metadata)
return next_tokens
def load_weights(self, weights: Iterable[Tuple[str,
torch.Tensor]]) -> Set[str]:
params_dict = dict(self.named_parameters())
loaded_params: Set[str] = set()
for name, loaded_weight in weights:
if "A_log" in name:
name = name.replace("A_log", "A")
# Skip loading extra bias for GPTQ models.
if name.endswith(".bias") and name not in params_dict:
continue
if is_pp_missing_parameter(name, self):
continue
param = params_dict[name]
weight_loader = getattr(param, "weight_loader",
default_weight_loader)
weight_loader(param, loaded_weight)
loaded_params.add(name)
return loaded_params