sglang0.4.5.post1/python/sglang/srt/models/olmo.py

377 lines
12 KiB
Python

# Copyright 2023-2024 SGLang Team
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ==============================================================================
# Adapted from
# https://github.com/vllm-project/vllm/blob/c7f2cf2b7f67bce5842fedfdba508440fe257375/vllm/model_executor/models/olmo.py#L1
"""Inference-only OLMo model compatible with HuggingFace weights."""
from typing import Iterable, Optional, Tuple
import torch
from torch import nn
from transformers import OlmoConfig
from sglang.srt.distributed import get_tensor_model_parallel_world_size
from sglang.srt.layers.activation import SiluAndMul
from sglang.srt.layers.linear import (
MergedColumnParallelLinear,
QKVParallelLinear,
RowParallelLinear,
)
from sglang.srt.layers.logits_processor import LogitsProcessor
from sglang.srt.layers.quantization.base_config import QuantizationConfig
from sglang.srt.layers.radix_attention import RadixAttention
from sglang.srt.layers.rotary_embedding import get_rope
from sglang.srt.layers.vocab_parallel_embedding import (
ParallelLMHead,
VocabParallelEmbedding,
)
from sglang.srt.model_executor.forward_batch_info import ForwardBatch
from sglang.srt.model_loader.weight_utils import default_weight_loader
from sglang.srt.utils import add_prefix, make_layers
class OlmoAttention(nn.Module):
"""
This is the attention block where the output is computed as
``Attention(LN(x))`` in ``MLP(LN(x + Attention(LN(x))))``
(plus another skip connection).
"""
def __init__(
self,
config: OlmoConfig,
layer_id: int = 0,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
):
super().__init__()
self.config = config
self.hidden_size = config.hidden_size
tensor_model_parallel_world_size = get_tensor_model_parallel_world_size()
self.total_num_heads = config.num_attention_heads
assert self.hidden_size % self.total_num_heads == 0
assert self.total_num_heads % tensor_model_parallel_world_size == 0
self.num_heads = self.total_num_heads // tensor_model_parallel_world_size
self.head_dim = self.hidden_size // self.total_num_heads
self.max_position_embeddings = config.max_position_embeddings
self.rope_theta = config.rope_theta
self.clip_qkv = config.clip_qkv
# Attention input projection. Projects x -> (q, k, v)
self.qkv_proj = QKVParallelLinear(
self.hidden_size,
self.head_dim,
self.total_num_heads,
bias=config.attention_bias,
prefix=add_prefix("qkv_proj", prefix),
)
# Rotary embeddings.
self.rotary_emb = get_rope(
self.head_dim,
rotary_dim=self.head_dim,
max_position=self.max_position_embeddings,
base=self.rope_theta,
)
self.scaling = self.head_dim**-0.5
self.attn = RadixAttention(
self.num_heads,
self.head_dim,
self.scaling,
num_kv_heads=self.num_heads,
layer_id=layer_id,
prefix=add_prefix("attn", prefix),
)
# Attention output projection.
self.o_proj = RowParallelLinear(
self.hidden_size,
self.hidden_size,
bias=config.attention_bias,
prefix=add_prefix("o_proj", prefix),
)
def forward(
self,
positions: torch.Tensor,
hidden_states: torch.Tensor,
forward_batch: ForwardBatch,
) -> torch.Tensor:
qkv, _ = self.qkv_proj(hidden_states)
if self.clip_qkv is not None:
qkv.clamp_(min=-self.clip_qkv, max=self.clip_qkv)
q, k, v = qkv.chunk(chunks=3, dim=-1)
q, k = self.rotary_emb(positions, q, k)
attn_output = self.attn(q, k, v, forward_batch)
output, _ = self.o_proj(attn_output)
return output
class OlmoMLP(nn.Module):
"""
This is the MLP block where the output is computed as
``MLP(LN(x))`` in ``MLP(LN(x + Attention(LN(x))))``
(plus another skip connection).
"""
def __init__(
self,
config: OlmoConfig,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
):
super().__init__()
self.config = config
self.hidden_size = config.hidden_size
self.intermediate_size = config.intermediate_size
# Feed-forward input projection.
self.gate_up_proj = MergedColumnParallelLinear(
self.hidden_size,
[self.intermediate_size] * 2,
bias=False,
quant_config=quant_config,
prefix=add_prefix("gate_up_proj", prefix),
)
# Activation function.
self.act_fn = SiluAndMul()
# Feed-forward output projection.
self.down_proj = RowParallelLinear(
self.intermediate_size,
self.hidden_size,
bias=False,
quant_config=quant_config,
prefix=add_prefix("down_proj", prefix),
)
def forward(
self,
x: torch.Tensor,
) -> torch.Tensor:
gate_up, _ = self.gate_up_proj(x)
x = self.act_fn(gate_up)
x, _ = self.down_proj(x)
return x
class OlmoDecoderLayer(nn.Module):
"""
This is a typical transformer block where the output is
computed as ``MLP(LN(x + Attention(LN(x))))``
(plus another skip connection).
"""
def __init__(
self,
config: OlmoConfig,
layer_id: int = 0,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
):
super().__init__()
# Attention block.
self.self_attn = OlmoAttention(
config,
layer_id,
quant_config,
prefix=add_prefix("self_attn", prefix),
)
# MLP block.
self.mlp = OlmoMLP(
config,
quant_config,
prefix=add_prefix("mlp", prefix),
)
# LayerNorm
self.input_layernorm = nn.LayerNorm(
config.hidden_size, elementwise_affine=False, bias=False
)
self.post_attention_layernorm = nn.LayerNorm(
config.hidden_size, elementwise_affine=False, bias=False
)
def forward(
self,
positions: torch.Tensor,
hidden_states: torch.Tensor,
forward_batch: ForwardBatch,
) -> Tuple[torch.Tensor, Optional[Tuple[torch.Tensor, torch.Tensor]]]:
# Attention block.
residual = hidden_states
hidden_states = self.input_layernorm(hidden_states)
hidden_states = self.self_attn(positions, hidden_states, forward_batch)
hidden_states = hidden_states + residual
# MLP block.
residual = hidden_states
hidden_states = self.post_attention_layernorm(hidden_states)
hidden_states = self.mlp(hidden_states)
hidden_states = residual + hidden_states
return hidden_states
class OlmoModel(nn.Module):
def __init__(
self,
config: OlmoConfig,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
):
super().__init__()
self.config = config
self.embed_tokens = VocabParallelEmbedding(
config.vocab_size,
config.hidden_size,
prefix=add_prefix("embed_tokens", prefix),
)
self.layers = make_layers(
config.num_hidden_layers,
lambda idx, prefix: OlmoDecoderLayer(
layer_id=idx,
config=config,
quant_config=quant_config,
prefix=prefix,
),
prefix=add_prefix("layers", prefix),
)
self.norm = nn.LayerNorm(
config.hidden_size, elementwise_affine=False, bias=False
)
def forward(
self,
input_ids: torch.Tensor,
positions: torch.Tensor,
forward_batch: ForwardBatch,
input_embeds: torch.Tensor = None,
) -> torch.Tensor:
"""
:param input_ids: A tensor of shape `(batch_size, seq_len)`.
"""
# Get embeddings of input.
# shape: (batch_size, seq_len, d_model)
if input_embeds is None:
hidden_states = self.embed_tokens(input_ids)
else:
hidden_states = input_embeds
# Apply blocks one-by-one.
for layer_id, decoder_layer in enumerate(self.layers):
# shape: (batch_size, seq_len, d_model)
hidden_states = decoder_layer(
positions,
hidden_states,
forward_batch,
)
# Apply final layer norm.
# shape: (batch_size, seq_len or 1, d_model)
hidden_states = self.norm(hidden_states)
return hidden_states
class OlmoForCausalLM(nn.Module):
"""
Extremely barebones HF model wrapper.
"""
def __init__(
self,
config: OlmoConfig,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
):
super().__init__()
self.config = config
self.model = OlmoModel(config, quant_config, prefix=add_prefix("model", prefix))
if config.tie_word_embeddings:
self.lm_head = self.model.embed_tokens
else:
self.unpadded_vocab_size = config.vocab_size
self.lm_head = ParallelLMHead(
self.unpadded_vocab_size,
config.hidden_size,
org_num_embeddings=config.vocab_size,
quant_config=quant_config,
prefix=add_prefix("lm_head", prefix),
)
self.logits_processor = LogitsProcessor(config)
def forward(
self,
input_ids: torch.Tensor,
positions: torch.Tensor,
forward_batch: ForwardBatch,
input_embeds: torch.Tensor = None,
) -> torch.Tensor:
hidden_states = self.model(
input_ids=input_ids,
positions=positions,
forward_batch=forward_batch,
input_embeds=input_embeds,
)
return self.logits_processor(
input_ids, hidden_states, self.lm_head, forward_batch
)
def load_weights(self, weights: Iterable[Tuple[str, torch.Tensor]]):
stacked_params_mapping = [
# (param_name, shard_name, shard_id)
("qkv_proj", "q_proj", "q"),
("qkv_proj", "k_proj", "k"),
("qkv_proj", "v_proj", "v"),
("gate_up_proj", "gate_proj", 0),
("gate_up_proj", "up_proj", 1),
]
params_dict = dict(self.named_parameters(remove_duplicate=False))
for name, loaded_weight in weights:
if "rotary_emb.inv_freq" in name:
continue
if "rotary_emb.cos_cached" in name or "rotary_emb.sin_cached" in name:
# Models trained using ColossalAI may include these tensors in
# the checkpoint. Skip them.
continue
if self.config.tie_word_embeddings and "lm_head.weight" in name:
continue
for param_name, weight_name, shard_id in stacked_params_mapping:
if weight_name not in name:
continue
name = name.replace(weight_name, param_name)
# Skip loading extra bias for GPTQ models.
if name.endswith(".bias") and name not in params_dict:
continue
param = params_dict[name]
weight_loader = param.weight_loader
weight_loader(param, loaded_weight, shard_id)
break
else:
# Skip loading extra bias for GPTQ models.
if name.endswith(".bias") and name not in params_dict:
continue
param = params_dict[name]
weight_loader = getattr(param, "weight_loader", default_weight_loader)
weight_loader(param, loaded_weight)
EntryClass = OlmoForCausalLM