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

147 lines
4.8 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.
"""
from sglang.srt.utils import add_prefix
# Adapted from
# https://github.com/SafeAILab/EAGLE/blob/main/eagle/model/cnets.py
"""Inference-only LLaMA-EAGLE model compatible with HuggingFace weights."""
from typing import Iterable, Optional, Tuple
import torch
from torch import nn
from transformers import LlamaConfig
from sglang.srt.layers.logits_processor import LogitsProcessor
from sglang.srt.layers.quantization.base_config import QuantizationConfig
from sglang.srt.layers.vocab_parallel_embedding import (
ParallelLMHead,
VocabParallelEmbedding,
)
from sglang.srt.model_executor.forward_batch_info import ForwardBatch
from sglang.srt.models.llama import LlamaDecoderLayer, LlamaForCausalLM
class LlamaDecoderLayer(LlamaDecoderLayer):
def __init__(
self,
config: LlamaConfig,
layer_id: int = 0,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
) -> None:
super().__init__(config, layer_id, quant_config, prefix)
# Skip the input_layernorm
# https://github.com/SafeAILab/EAGLE/blob/35c78f6cdc19a73e05cf5c330b4c358dad970c6a/eagle/model/cnets.py#L427
if layer_id == 0:
del self.input_layernorm
setattr(self, "input_layernorm", lambda x: x)
class LlamaModel(nn.Module):
def __init__(
self,
config: LlamaConfig,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
) -> None:
super().__init__()
self.config = config
self.vocab_size = config.vocab_size
self.embed_tokens = VocabParallelEmbedding(
config.vocab_size,
config.hidden_size,
prefix=add_prefix("embed_tokens", prefix),
)
self.layers = nn.ModuleList(
[
LlamaDecoderLayer(
config,
i,
quant_config=quant_config,
prefix=add_prefix(f"layers.{i}", prefix),
)
for i in range(config.num_hidden_layers)
]
)
self.fc = torch.nn.Linear(config.hidden_size * 2, config.hidden_size)
def forward(
self,
input_ids: torch.Tensor,
positions: torch.Tensor,
forward_batch: ForwardBatch,
input_embeds: torch.Tensor = None,
) -> torch.Tensor:
if input_embeds is None:
hidden_states = self.embed_tokens(input_ids)
else:
hidden_states = input_embeds
hidden_states = self.fc(
torch.cat((hidden_states, forward_batch.spec_info.hidden_states), dim=-1)
)
residual = None
for i in range(len(self.layers)):
layer = self.layers[i]
hidden_states, residual = layer(
positions,
hidden_states,
forward_batch,
residual,
)
return hidden_states + residual
class LlamaForCausalLMEagle(LlamaForCausalLM):
def __init__(
self,
config: LlamaConfig,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
) -> None:
nn.Module.__init__(self)
self.config = config
self.quant_config = quant_config
self.model = LlamaModel(
config, quant_config=quant_config, prefix=add_prefix("model", prefix)
)
# Llama 3.2 1B Instruct set tie_word_embeddings to True
# Llama 3.1 8B Instruct set tie_word_embeddings to False
if self.config.tie_word_embeddings:
self.lm_head = self.model.embed_tokens
else:
self.lm_head = ParallelLMHead(
getattr(config, "hot_vocab_size", config.vocab_size),
config.hidden_size,
quant_config=quant_config,
prefix=add_prefix("lm_head", prefix),
)
self.logits_processor = LogitsProcessor(config)
self.capture_aux_hidden_states = False
def load_weights(self, weights: Iterable[Tuple[str, torch.Tensor]]):
for name, loaded_weight in weights:
if "lm_head" not in name:
name = "model." + name
super().load_weights([(name, loaded_weight)])
EntryClass = [LlamaForCausalLMEagle]