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

440 lines
15 KiB
Python

# coding=utf-8
# Copyright 2022 EleutherAI and the HuggingFace Inc. team. All rights reserved.
#
# This code is based on EleutherAI's GPT-NeoX library and the GPT-NeoX
# and OPT implementations in this library. It has been modified from its
# original forms to accommodate minor architectural differences compared
# to GPT-NeoX and OPT used by the Meta AI team that trained the model.
#
# 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.
"""Inference-only BaiChuan model compatible with HuggingFace weights."""
import math
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_rank,
get_tensor_model_parallel_world_size,
)
from sglang.srt.layers.activation import SiluAndMul
from sglang.srt.layers.layernorm import RMSNorm
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
def _get_alibi_slopes(total_num_heads: int) -> torch.Tensor:
closest_power_of_2 = 2 ** math.floor(math.log2(total_num_heads))
base = torch.tensor(
2 ** (-(2 ** -(math.log2(closest_power_of_2) - 3))),
dtype=torch.float32,
)
powers = torch.arange(1, 1 + closest_power_of_2, dtype=torch.int32)
slopes = torch.pow(base, powers)
if closest_power_of_2 != total_num_heads:
extra_base = torch.tensor(
2 ** (-(2 ** -(math.log2(2 * closest_power_of_2) - 3))),
dtype=torch.float32,
)
num_remaining_heads = min(
closest_power_of_2, total_num_heads - closest_power_of_2
)
extra_powers = torch.arange(
start=1, end=1 + 2 * num_remaining_heads, step=2, dtype=torch.int32
)
slopes = torch.cat([slopes, torch.pow(extra_base, extra_powers)], dim=0)
return slopes
class BaiChuanMLP(nn.Module):
def __init__(
self,
hidden_size: int,
intermediate_size: int,
hidden_act: str,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
):
super().__init__()
self.gate_up_proj = MergedColumnParallelLinear(
hidden_size,
[intermediate_size] * 2,
bias=False,
quant_config=quant_config,
prefix=add_prefix("gate_up_proj", prefix),
)
self.down_proj = RowParallelLinear(
intermediate_size,
hidden_size,
bias=False,
quant_config=quant_config,
prefix=add_prefix("down_proj", prefix),
)
if hidden_act != "silu":
raise ValueError(
f"Unsupported activation: {hidden_act}. "
"Only silu is supported for now."
)
self.act_fn = SiluAndMul()
def forward(self, x):
gate_up, _ = self.gate_up_proj(x)
x = self.act_fn(gate_up)
x, _ = self.down_proj(x)
return x
class BaiChuanAttention(nn.Module):
"""Multi-headed attention from 'Attention Is All You Need' paper"""
def __init__(
self,
hidden_size: int,
num_heads: int,
position_embedding: str,
rope_theta: float = 10000,
max_position_embeddings: int = 8192,
quant_config: Optional[QuantizationConfig] = None,
layer_id: int = 0,
prefix: str = "",
):
super().__init__()
self.hidden_size = hidden_size
tensor_model_parallel_world_size = get_tensor_model_parallel_world_size()
tp_size = get_tensor_model_parallel_world_size()
self.total_num_heads = num_heads
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 = hidden_size // self.total_num_heads
self.postion_embedding = position_embedding
self.rope_theta = rope_theta
self.max_position_embeddings = max_position_embeddings
self.total_num_kv_heads = self.num_heads
if self.total_num_kv_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_kv_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_kv_heads == 0
self.num_kv_heads = max(1, self.total_num_kv_heads // tp_size)
# pylint: disable=invalid-name
self.W_pack = QKVParallelLinear(
hidden_size,
self.head_dim,
self.total_num_heads,
self.total_num_heads,
bias=False,
quant_config=quant_config,
)
self.o_proj = RowParallelLinear(
self.total_num_heads * self.head_dim,
hidden_size,
bias=False,
quant_config=quant_config,
)
# Create the alibi slopes and slice them.
if self.postion_embedding == "ALIBI":
tp_rank = get_tensor_model_parallel_rank()
head_start = tp_rank * self.num_heads
head_end = (tp_rank + 1) * self.num_heads
alibi_slopes = _get_alibi_slopes(self.total_num_heads)
alibi_slopes = alibi_slopes[head_start:head_end].tolist()
scaling = self.head_dim**-0.5
self.attn = RadixAttention(
self.num_heads,
self.head_dim,
scaling,
num_kv_heads=self.num_kv_heads,
layer_id=layer_id,
prefix=add_prefix("attn", prefix),
)
else:
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_kv_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.W_pack(hidden_states)
q, k, v = qkv.chunk(chunks=3, dim=-1)
if self.postion_embedding != "ALIBI":
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 BaiChuanDecoderLayer(nn.Module):
def __init__(
self,
config: PretrainedConfig,
position_embedding: str,
layer_id: int = 0,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
):
super().__init__()
self.hidden_size = config.hidden_size
rope_theta = getattr(config, "rope_theta", 10000)
max_position_embeddings = getattr(config, "max_position_embeddings", 8192)
self.self_attn = BaiChuanAttention(
hidden_size=self.hidden_size,
num_heads=config.num_attention_heads,
position_embedding=position_embedding,
rope_theta=rope_theta,
layer_id=layer_id,
max_position_embeddings=max_position_embeddings,
quant_config=quant_config,
prefix=add_prefix("self_attn", prefix),
)
self.mlp = BaiChuanMLP(
hidden_size=self.hidden_size,
intermediate_size=config.intermediate_size,
hidden_act=config.hidden_act,
quant_config=quant_config,
prefix=add_prefix("mlp", prefix),
)
self.input_layernorm = RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
self.post_attention_layernorm = RMSNorm(
config.hidden_size, eps=config.rms_norm_eps
)
def forward(
self,
positions: torch.Tensor,
hidden_states: torch.Tensor,
forward_batch: ForwardBatch,
residual: Optional[torch.Tensor],
) -> Tuple[torch.Tensor, torch.Tensor]:
# Self Attention
if residual is None:
residual = hidden_states
hidden_states = self.input_layernorm(hidden_states)
else:
hidden_states, residual = self.input_layernorm(hidden_states, residual)
hidden_states = self.self_attn(
positions=positions,
hidden_states=hidden_states,
forward_batch=forward_batch,
)
# Fully Connected
hidden_states, residual = self.post_attention_layernorm(hidden_states, residual)
hidden_states = self.mlp(hidden_states)
return hidden_states, residual
class BaiChuanModel(nn.Module):
def __init__(
self,
config: PretrainedConfig,
position_embedding: str,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
):
super().__init__()
self.config = config
self.padding_idx = config.pad_token_id
self.vocab_size = config.vocab_size
self.embed_tokens = VocabParallelEmbedding(
config.vocab_size,
config.hidden_size,
)
self.layers = nn.ModuleList(
[
BaiChuanDecoderLayer(
config,
layer_id=i,
position_embedding=position_embedding,
quant_config=quant_config,
prefix=add_prefix(f"layers.{i}", prefix),
)
for i in range(config.num_hidden_layers)
]
)
self.norm = RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
def forward(
self,
input_ids: torch.Tensor,
positions: torch.Tensor,
forward_batch: ForwardBatch,
) -> torch.Tensor:
hidden_states = self.embed_tokens(input_ids)
residual = None
for i in range(len(self.layers)):
layer = self.layers[i]
hidden_states, residual = layer(
positions,
hidden_states,
forward_batch,
residual,
)
hidden_states, _ = self.norm(hidden_states, residual)
return hidden_states
class BaiChuanBaseForCausalLM(nn.Module):
packed_modules_mapping = {
"W_pack": ["W_pack"],
"gate_up_proj": [
"gate_proj",
"up_proj",
],
}
# LoRA specific attributes
supported_lora_modules = [
"W_pack",
"o_proj",
"gate_up_proj",
"down_proj",
]
embedding_modules = {}
embedding_padding_modules = []
def __init__(
self,
config: PretrainedConfig,
position_embedding: str,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
):
super().__init__()
self.config = config
self.quant_config = quant_config
self.model = BaiChuanModel(
config, position_embedding, quant_config, prefix=add_prefix("model", prefix)
)
if self.config.tie_word_embeddings:
self.lm_head = self.model.embed_tokens
else:
self.lm_head = ParallelLMHead(
config.vocab_size,
config.hidden_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,
) -> torch.Tensor:
hidden_states = self.model(input_ids, positions, forward_batch)
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)
("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 name == "lm_head.weight":
# Unlike Baichuan, Baichuan2 normalizes the head weights.
# Refer to:
# https://huggingface.co/baichuan-inc/Baichuan2-7B-Chat/blob/84603cde5ebffb6084e476cfaeceaf0b8b91fe54/modeling_baichuan.py#L508
# Distinguish between Baichuan and Baichuan2 by checking the
# vocab size. This is suggested by
# https://github.com/vllm-project/vllm/pull/1022#discussion_r1325652704
is_baichuan2 = self.config.vocab_size == 125696
if is_baichuan2:
loaded_weight = torch.nn.functional.normalize(loaded_weight)
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)
class BaichuanForCausalLM(BaiChuanBaseForCausalLM):
"""Baichuan 13B and Baichuan2 7B/13B."""
def __init__(
self,
config,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
):
if config.hidden_size == 4096: # baichuan2 7b
super().__init__(config, "ROPE", quant_config, prefix=prefix)
else: # baichuan 13b, baichuan2 13b
super().__init__(config, "ALIBI", quant_config, prefix=prefix)
EntryClass = [BaichuanForCausalLM]