Harry Mellor 8fcaaf6a16
Update Optional[x] -> x | None and Union[x, y] to x | y (#26633)
Signed-off-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>
2025-10-12 09:51:31 -07:00

302 lines
11 KiB
Python

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
"""PyTorch MAMBA2 model."""
from collections.abc import Iterable
import torch
from torch import nn
from transformers import MambaConfig
from vllm.compilation.decorators import support_torch_compile
from vllm.config import CacheConfig, ModelConfig, VllmConfig
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_mixer2 import MambaMixer2
from vllm.model_executor.layers.mamba.mamba_utils import (
MambaStateDtypeCalculator,
MambaStateShapeCalculator,
)
from vllm.model_executor.layers.quantization import QuantizationConfig
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
from vllm.sequence import IntermediateTensors
from .utils import (
AutoWeightsLoader,
is_pp_missing_parameter,
make_empty_intermediate_tensors_factory,
make_layers,
maybe_prefix,
)
KVCache = tuple[torch.Tensor, torch.Tensor]
class Mamba2DecoderLayer(nn.Module):
def __init__(
self,
config: MambaConfig,
model_config: ModelConfig | None = None,
cache_config: CacheConfig | None = None,
quant_config: QuantizationConfig | None = None,
prefix: str = "",
) -> None:
super().__init__()
self.config = config
self.mixer = MambaMixer2(
hidden_size=config.hidden_size,
ssm_state_size=config.state_size,
conv_kernel_size=config.conv_kernel,
intermediate_size=getattr(
config, "intermediate_size", config.expand * config.hidden_size
),
use_conv_bias=config.use_conv_bias,
use_bias=config.use_bias,
n_groups=config.n_groups,
num_heads=config.num_heads,
head_dim=config.head_dim,
rms_norm_eps=config.layer_norm_epsilon,
activation=config.hidden_act,
model_config=model_config,
cache_config=cache_config,
quant_config=quant_config,
prefix=f"{prefix}.mixer",
)
self.norm = RMSNorm(config.hidden_size, eps=config.layer_norm_epsilon)
def forward(
self,
hidden_states: torch.Tensor,
residual: torch.Tensor | None,
**kwargs,
):
if residual is None:
residual = hidden_states
hidden_states = self.norm(hidden_states)
else:
hidden_states, residual = self.norm(hidden_states, residual)
output = torch.empty_like(hidden_states)
self.mixer(hidden_states, output)
return output, residual
@support_torch_compile
class Mamba2Model(nn.Module):
def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""):
super().__init__()
config = vllm_config.model_config.hf_config
model_config = vllm_config.model_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)
assert not is_lora_enabled
self.config = config
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: Mamba2DecoderLayer(
config,
model_config=model_config,
cache_config=cache_config,
quant_config=quant_config,
prefix=prefix,
),
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,
intermediate_tensors: IntermediateTensors | None = None,
inputs_embeds: torch.Tensor | None = 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, layer in enumerate(self.layers):
hidden_states, residual = layer(
positions=positions, hidden_states=hidden_states, residual=residual
)
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
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
class Mamba2ForCausalLM(nn.Module, HasInnerState, IsAttentionFree):
@classmethod
def get_mamba_state_dtype_from_config(
cls,
vllm_config: "VllmConfig",
) -> tuple[torch.dtype, torch.dtype]:
return MambaStateDtypeCalculator.mamba2_state_dtype(
vllm_config.model_config.dtype,
vllm_config.cache_config.mamba_cache_dtype,
vllm_config.cache_config.mamba_ssm_cache_dtype,
)
@classmethod
def get_mamba_state_shape_from_config(
cls,
vllm_config: "VllmConfig",
) -> tuple[tuple[int, int], tuple[int, int, int]]:
"""Calculate shapes for Mamba's convolutional and state caches.
Args:
vllm_config: vLLM config
Returns:
Tuple containing:
- conv_state_shape: Shape for convolutional state cache
- temporal_state_shape: Shape for state space model cache
"""
parallel_config = vllm_config.parallel_config
hf_config = vllm_config.model_config.hf_config
intermediate_size = hf_config.expand * hf_config.hidden_size
return MambaStateShapeCalculator.mamba2_state_shape(
intermediate_size=intermediate_size,
tp_world_size=parallel_config.tensor_parallel_size,
n_groups=hf_config.n_groups,
num_heads=hf_config.num_heads,
head_dim=hf_config.head_dim,
state_size=hf_config.state_size,
conv_kernel=hf_config.conv_kernel,
)
def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""):
config = vllm_config.model_config.hf_config
lora_config = vllm_config.lora_config
scheduler_config = vllm_config.scheduler_config
super().__init__()
self.config = config
self.vllm_config = vllm_config
self.scheduler_config = scheduler_config
self.model_config = vllm_config.model_config
self.backbone = Mamba2Model(
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
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,
prefix=maybe_prefix(prefix, "lm_head"),
)
if config.tie_word_embeddings:
self.lm_head = self.lm_head.tie_weights(self.backbone.embeddings)
self.logits_processor = LogitsProcessor(
self.unpadded_vocab_size, config.vocab_size
)
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: IntermediateTensors | None = None,
inputs_embeds: torch.Tensor | None = None,
**kwargs,
):
hidden_states = self.backbone(
input_ids, positions, 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 compute_logits(self, hidden_states: torch.Tensor) -> torch.Tensor:
logits = self.logits_processor(self.lm_head, hidden_states)
return logits
def load_weights(self, weights: Iterable[tuple[str, torch.Tensor]]) -> set[str]:
loader = AutoWeightsLoader(self)
return loader.load_weights(weights)