vllm/vllm/model_executor/models/phi.py
2024-01-12 12:16:49 -08:00

306 lines
11 KiB
Python

# coding=utf-8
# Adapted from
# https://huggingface.co/microsoft/phi-1_5/blob/main/modeling_phi.py
# Copyright 2023 The vLLM team.
# Copyright (c) Microsoft Corporation.
# Licensed under the MIT license.
#
# BSD 3-Clause License
#
# Copyright (c) 2022, Tri Dao, trid@cs.stanford.edu.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright notice, this
# list of conditions and the following disclaimer.
#
# * Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions and the following disclaimer in the documentation
# and/or other materials provided with the distribution.
#
# * Neither the name of the copyright holder nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
"""Inference-only Phi-1.5 model compatible with HuggingFace weights."""
from typing import List, Optional, Tuple
import torch
from torch import nn
from transformers import PretrainedConfig
from vllm.model_executor.input_metadata import InputMetadata
from vllm.model_executor.layers.activation import get_act_fn
from vllm.model_executor.layers.attention import PagedAttention
from vllm.model_executor.layers.linear import (ColumnParallelLinear,
LinearMethodBase,
QKVParallelLinear,
RowParallelLinear)
from vllm.model_executor.layers.rotary_embedding import get_rope
from vllm.model_executor.layers.sampler import Sampler
from vllm.model_executor.layers.vocab_parallel_embedding import (
VocabParallelEmbedding, ParallelLMHead)
from vllm.model_executor.parallel_utils.parallel_state import (
get_tensor_model_parallel_world_size)
from vllm.model_executor.sampling_metadata import SamplingMetadata
from vllm.model_executor.weight_utils import (default_weight_loader,
hf_model_weights_iterator)
from vllm.sequence import SamplerOutput
KVCache = Tuple[torch.Tensor, torch.Tensor]
class PhiAttention(nn.Module):
def __init__(self,
config: PretrainedConfig,
linear_method: Optional[LinearMethodBase] = None):
super().__init__()
self.total_num_heads = config.num_attention_heads
self.hidden_size = config.hidden_size
self.head_size = self.hidden_size // self.total_num_heads
tensor_model_parallel_world_size = (
get_tensor_model_parallel_world_size())
assert self.total_num_heads % tensor_model_parallel_world_size == 0
self.num_heads = (self.total_num_heads //
tensor_model_parallel_world_size)
# pylint: disable=C0103
self.qkv_proj = QKVParallelLinear(
self.hidden_size,
self.head_size,
self.total_num_heads,
bias=True,
linear_method=linear_method,
)
self.dense = RowParallelLinear(
self.hidden_size,
self.hidden_size,
linear_method=linear_method,
)
scaling = self.head_size**-0.5
rotary_dim = int(config.partial_rotary_factor *
(config.hidden_size // config.num_attention_heads))
assert rotary_dim % 2 == 0
# pylint: disable=C0301
# Refer to:
# https://huggingface.co/microsoft/phi-1_5/blob/d212a789620c380ff32ca1d1ee9943a777360987/modeling_phi.py#L518
rope_theta = 10000
max_position_embeddings = getattr(config, "n_positions", 2048)
self.rotary_emb = get_rope(
self.head_size,
rotary_dim=rotary_dim,
max_position=max_position_embeddings,
base=rope_theta,
)
self.attn = PagedAttention(self.num_heads, self.head_size, scaling)
def forward(
self,
position_ids: torch.Tensor,
hidden_states: torch.Tensor,
kv_cache: KVCache,
input_metadata: InputMetadata,
) -> torch.Tensor:
qkv, _ = self.qkv_proj(hidden_states)
q, k, v = qkv.chunk(chunks=3, dim=-1)
q, k = self.rotary_emb(position_ids, q, k)
k_cache, v_cache = kv_cache
attn_output = self.attn(q, k, v, k_cache, v_cache, input_metadata)
output, _ = self.dense(attn_output)
return output
class PhiMLP(nn.Module):
def __init__(self,
config: PretrainedConfig,
linear_method: Optional[LinearMethodBase] = None):
super().__init__()
n_inner = getattr(config, "n_inner", None)
n_inner = n_inner if n_inner is not None else 4 * config.hidden_size
self.fc1 = ColumnParallelLinear(
config.hidden_size,
n_inner,
linear_method=linear_method,
)
self.fc2 = RowParallelLinear(
n_inner,
config.hidden_size,
linear_method=linear_method,
)
quant_config = getattr(linear_method, "quant_config", None)
self.act = get_act_fn(config.hidden_act, quant_config, n_inner)
def forward(self, hidden_states):
hidden_states, _ = self.fc1(hidden_states)
hidden_states = self.act(hidden_states)
hidden_states, _ = self.fc2(hidden_states)
return hidden_states
class PhiLayer(nn.Module):
def __init__(self,
config: PretrainedConfig,
linear_method: Optional[LinearMethodBase] = None):
super().__init__()
self.input_layernorm = nn.LayerNorm(config.hidden_size,
eps=config.layer_norm_eps)
self.self_attn = PhiAttention(config, linear_method)
self.mlp = PhiMLP(config, linear_method)
def forward(
self,
position_ids: torch.Tensor,
hidden_states: torch.Tensor,
kv_cache: KVCache,
input_metadata: InputMetadata,
) -> torch.Tensor:
residual = hidden_states
hidden_states = self.input_layernorm(hidden_states)
attn_outputs = self.self_attn(
position_ids=position_ids,
hidden_states=hidden_states,
kv_cache=kv_cache,
input_metadata=input_metadata,
)
feed_forward_hidden_states = self.mlp(hidden_states)
hidden_states = attn_outputs + feed_forward_hidden_states + residual
return hidden_states
class PhiModel(nn.Module):
def __init__(self,
config: PretrainedConfig,
linear_method: Optional[LinearMethodBase] = None):
super().__init__()
self.config = config
self.linear_method = linear_method
self.embed_tokens = VocabParallelEmbedding(config.vocab_size,
config.hidden_size)
self.layers = nn.ModuleList([
PhiLayer(config, linear_method)
for _ in range(config.num_hidden_layers)
])
self.final_layernorm = nn.LayerNorm(config.hidden_size,
eps=config.layer_norm_eps)
def forward(
self,
input_ids: torch.Tensor,
positions: torch.Tensor,
kv_caches: List[KVCache],
input_metadata: InputMetadata,
) -> torch.Tensor:
hidden_states = self.embed_tokens(input_ids)
for i in range(self.config.num_hidden_layers):
layer = self.layers[i]
hidden_states = layer(
positions,
hidden_states,
kv_caches[i],
input_metadata,
)
hidden_states = self.final_layernorm(hidden_states)
return hidden_states
class PhiForCausalLM(nn.Module):
def __init__(self,
config: PretrainedConfig,
linear_method: Optional[LinearMethodBase] = None):
super().__init__()
self.config = config
self.linear_method = linear_method
self.model = PhiModel(config, linear_method)
self.lm_head = ParallelLMHead(config.vocab_size,
config.hidden_size,
bias=True)
self.sampler = Sampler(config.vocab_size)
def forward(
self,
input_ids: torch.Tensor,
positions: torch.Tensor,
kv_caches: List[KVCache],
input_metadata: InputMetadata,
) -> torch.Tensor:
hidden_states = self.model(input_ids, positions, kv_caches,
input_metadata)
return hidden_states
def sample(
self,
hidden_states: torch.Tensor,
sampling_metadata: SamplingMetadata,
) -> Optional[SamplerOutput]:
head = self.lm_head
next_tokens = self.sampler(head.weight, hidden_states,
sampling_metadata, head.bias)
return next_tokens
def load_weights(self,
model_name_or_path: str,
cache_dir: Optional[str] = None,
load_format: str = "auto",
revision: Optional[str] = None):
stacked_params_mapping = [
# (param_name, shard_name, shard_id)
("qkv_proj", "q_proj", "q"),
("qkv_proj", "k_proj", "k"),
("qkv_proj", "v_proj", "v")
]
params_dict = dict(self.named_parameters())
for name, loaded_weight in hf_model_weights_iterator(
model_name_or_path, cache_dir, load_format, revision):
if "rotary_emb.inv_freq" 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
# pylint: disable=E1136
param = params_dict[name]
weight_loader = getattr(param, "weight_loader",
default_weight_loader)
weight_loader(param, loaded_weight)