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

331 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/stablelm.py#L1
"""
Inference-only StableLM-2 (https://huggingface.co/stabilityai/stablelm-2-1_6b)
model compatible with HuggingFace weights.
"""
from typing import Iterable, Optional, Tuple
import torch
from torch import nn
from transformers import PretrainedConfig
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
class StablelmMLP(nn.Module):
def __init__(
self,
config: PretrainedConfig,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
) -> None:
super().__init__()
self.config = config
self.hidden_size = config.hidden_size
self.intermediate_size = config.intermediate_size
self.gate_up_proj = MergedColumnParallelLinear(
config.hidden_size,
[config.intermediate_size] * 2,
bias=False,
quant_config=quant_config,
prefix=add_prefix("gate_up_proj", prefix),
)
self.down_proj = RowParallelLinear(
config.intermediate_size,
config.hidden_size,
bias=False,
quant_config=quant_config,
prefix=add_prefix("down_proj", prefix),
)
self.act_fn = SiluAndMul()
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 StablelmAttention(nn.Module):
def __init__(
self,
config: PretrainedConfig,
layer_id: int = 0,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
) -> None:
super().__init__()
self.config = config
self.hidden_size = config.hidden_size
tp_size = get_tensor_model_parallel_world_size()
self.total_num_heads = config.num_attention_heads
self.num_heads = self.total_num_heads // tp_size
self.total_num_key_value_heads = config.num_key_value_heads
if self.total_num_key_value_heads >= tp_size:
# Number of KV heads is greater than TP size, so we partition
# the KV heads across multiple tensor parallel GPUs.
assert self.total_num_key_value_heads % tp_size == 0
else:
# Number of KV heads is less than TP size, so we replicate
# the KV heads across multiple tensor parallel GPUs.
assert tp_size % self.total_num_key_value_heads == 0
self.num_key_value_heads = max(1, self.total_num_key_value_heads // tp_size)
self.head_dim = self.hidden_size // self.total_num_heads
self.max_position_embeddings = config.max_position_embeddings
rope_pct = getattr(
config, "rope_pct", getattr(config, "partial_rotary_factor", 1)
)
self.rotary_ndims = int(self.head_dim * rope_pct)
self.scaling = self.head_dim**-0.5
self.q_size = self.num_heads * self.head_dim
self.kv_size = self.num_key_value_heads * self.head_dim
self.qkv_bias = getattr(config, "use_qkv_bias", False)
if (self.head_dim * self.num_heads * tp_size) != self.hidden_size:
raise ValueError(
f"hidden_size must be divisible by num_heads "
f"(got `hidden_size`: {self.hidden_size}"
f" and `num_heads`: {self.num_heads})."
)
self.qkv_proj = QKVParallelLinear(
self.hidden_size,
self.head_dim,
self.total_num_heads,
self.total_num_key_value_heads,
self.qkv_bias,
quant_config=quant_config,
prefix=add_prefix("qkv_proj", prefix),
)
self.o_proj = RowParallelLinear(
self.total_num_heads * self.head_dim,
self.hidden_size,
bias=False,
quant_config=quant_config,
prefix=add_prefix("o_proj", prefix),
)
self.rotary_emb = get_rope(
self.head_dim,
rotary_dim=self.rotary_ndims,
max_position=self.config.max_position_embeddings,
base=self.config.rope_theta,
)
self.attn = RadixAttention(
self.num_heads,
self.head_dim,
self.scaling,
num_kv_heads=self.num_key_value_heads,
layer_id=layer_id,
prefix=add_prefix("attn", prefix),
)
def forward(
self,
positions: torch.Tensor,
hidden_states: torch.Tensor,
forward_batch: ForwardBatch,
) -> torch.Tensor:
qkv, _ = self.qkv_proj(hidden_states)
q, k, v = qkv.split([self.q_size, self.kv_size, self.kv_size], 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 StablelmDecoderLayer(nn.Module):
def __init__(
self,
config: PretrainedConfig,
layer_id: int = 0,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
) -> None:
super().__init__()
self.self_attn = StablelmAttention(
config, layer_id=layer_id, prefix=add_prefix("self_attn", prefix)
)
self.mlp = StablelmMLP(
config, quant_config=quant_config, prefix=add_prefix("mlp", prefix)
)
norm_eps = getattr(config, "norm_eps", getattr(config, "layer_norm_eps", 1e-05))
self.input_layernorm = nn.LayerNorm(config.hidden_size, eps=norm_eps)
self.post_attention_layernorm = nn.LayerNorm(config.hidden_size, eps=norm_eps)
def forward(
self,
positions: torch.Tensor,
hidden_states: torch.Tensor,
forward_batch: ForwardBatch,
) -> Tuple[torch.Tensor, torch.Tensor]:
# Self Attention
residual = hidden_states
hidden_states = self.input_layernorm(hidden_states)
hidden_states = self.self_attn(
positions=positions,
hidden_states=hidden_states,
forward_batch=forward_batch,
)
hidden_states = residual + hidden_states
# Fully Connected
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, residual
class StableLMEpochModel(nn.Module):
def __init__(
self,
config: PretrainedConfig,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
) -> None:
super().__init__()
self.embed_tokens = VocabParallelEmbedding(
config.vocab_size,
config.hidden_size,
prefix=add_prefix("embed_tokens", prefix),
)
self.layers = nn.ModuleList(
[
StablelmDecoderLayer(
config,
i,
quant_config=quant_config,
prefix=add_prefix(f"layers.{i}", prefix),
)
for i in range(config.num_hidden_layers)
]
)
norm_eps = getattr(config, "norm_eps", getattr(config, "layer_norm_eps", 1e-05))
self.norm = nn.LayerNorm(config.hidden_size, eps=norm_eps)
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
for i in range(len(self.layers)):
layer = self.layers[i]
hidden_states, residual = layer(
positions,
hidden_states,
forward_batch,
)
hidden_states = self.norm(hidden_states)
return hidden_states
class StableLmForCausalLM(nn.Module):
def __init__(
self,
config: PretrainedConfig,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
) -> None:
super().__init__()
self.config = config
self.quant_config = quant_config
self.model = StableLMEpochModel(
config, quant_config=quant_config, prefix=add_prefix("model", prefix)
)
self.lm_head = ParallelLMHead(
config.vocab_size, config.hidden_size, prefix=add_prefix("lm_head", prefix)
)
self.logits_processor = LogitsProcessor(config)
@torch.no_grad()
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, positions, forward_batch, 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())
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
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 = StableLmForCausalLM