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sglang/python/sglang/srt/models/llama.py
2024-11-03 13:27:12 -08:00

433 lines
16 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/llama.py#L1
"""Inference-only LLaMA model compatible with HuggingFace weights."""
from typing import Any, Dict, Iterable, Optional, Tuple
import torch
from torch import nn
from transformers import LlamaConfig
from vllm.distributed import get_tensor_model_parallel_world_size
from vllm.model_executor.layers.rotary_embedding import get_rope
from vllm.model_executor.model_loader.weight_utils import default_weight_loader
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, LogitsProcessorOutput
from sglang.srt.layers.pooler import Pooler, PoolingType
from sglang.srt.layers.quantization.base_config import QuantizationConfig
from sglang.srt.layers.radix_attention import RadixAttention
from sglang.srt.layers.torchao_utils import apply_torchao_config_
from sglang.srt.layers.vocab_parallel_embedding import (
ParallelLMHead,
VocabParallelEmbedding,
)
from sglang.srt.managers.schedule_batch import global_server_args_dict
from sglang.srt.model_executor.forward_batch_info import ForwardBatch
class LlamaMLP(nn.Module):
def __init__(
self,
hidden_size: int,
intermediate_size: int,
hidden_act: str,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
) -> None:
super().__init__()
self.gate_up_proj = MergedColumnParallelLinear(
hidden_size,
[intermediate_size] * 2,
bias=False,
quant_config=quant_config,
prefix=f"{prefix}.gate_up_proj",
)
self.down_proj = RowParallelLinear(
intermediate_size,
hidden_size,
bias=False,
quant_config=quant_config,
prefix=f"{prefix}.down_proj",
)
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 LlamaAttention(nn.Module):
def __init__(
self,
config: LlamaConfig,
hidden_size: int,
num_heads: int,
num_kv_heads: int,
layer_id: int = 0,
rope_theta: float = 10000,
rope_scaling: Optional[Dict[str, Any]] = None,
rope_is_neox_style: bool = True,
max_position_embeddings: int = 8192,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
) -> None:
super().__init__()
self.hidden_size = hidden_size
tp_size = get_tensor_model_parallel_world_size()
self.total_num_heads = num_heads
assert self.total_num_heads % tp_size == 0
self.num_heads = self.total_num_heads // tp_size
self.total_num_kv_heads = num_kv_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)
# MistralConfig has an optional head_dim introduced by Mistral-Nemo
self.head_dim = getattr(
config, "head_dim", self.hidden_size // self.total_num_heads
)
self.q_size = self.num_heads * self.head_dim
self.kv_size = self.num_kv_heads * self.head_dim
self.scaling = self.head_dim**-0.5
self.rope_theta = rope_theta
self.max_position_embeddings = max_position_embeddings
self.qkv_proj = QKVParallelLinear(
hidden_size,
self.head_dim,
self.total_num_heads,
self.total_num_kv_heads,
bias=False,
quant_config=quant_config,
prefix=f"{prefix}.qkv_proj",
)
self.o_proj = RowParallelLinear(
self.total_num_heads * self.head_dim,
hidden_size,
bias=False,
quant_config=quant_config,
prefix=f"{prefix}.o_proj",
)
self.rotary_emb = get_rope(
self.head_dim,
rotary_dim=self.head_dim,
max_position=max_position_embeddings,
base=rope_theta,
rope_scaling=rope_scaling,
is_neox_style=rope_is_neox_style,
)
self.attn = RadixAttention(
self.num_heads,
self.head_dim,
self.scaling,
num_kv_heads=self.num_kv_heads,
layer_id=layer_id,
)
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 LlamaDecoderLayer(nn.Module):
def __init__(
self,
config: LlamaConfig,
layer_id: int = 0,
quant_config: Optional[QuantizationConfig] = None,
prefix: str = "",
) -> None:
super().__init__()
self.hidden_size = config.hidden_size
rope_theta = getattr(config, "rope_theta", 10000)
rope_scaling = getattr(config, "rope_scaling", None)
if rope_scaling is not None and getattr(
config, "original_max_position_embeddings", None
):
rope_scaling["original_max_position_embeddings"] = (
config.original_max_position_embeddings
)
rope_is_neox_style = getattr(config, "rope_is_neox_style", True)
max_position_embeddings = getattr(config, "max_position_embeddings", 8192)
self.self_attn = LlamaAttention(
config=config,
hidden_size=self.hidden_size,
num_heads=config.num_attention_heads,
num_kv_heads=config.num_key_value_heads,
layer_id=layer_id,
rope_theta=rope_theta,
rope_scaling=rope_scaling,
rope_is_neox_style=rope_is_neox_style,
max_position_embeddings=max_position_embeddings,
quant_config=quant_config,
prefix=f"{prefix}.self_attn",
)
self.mlp = LlamaMLP(
hidden_size=self.hidden_size,
intermediate_size=config.intermediate_size,
hidden_act=config.hidden_act,
quant_config=quant_config,
prefix=f"{prefix}.mlp",
)
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 LlamaModel(nn.Module):
def __init__(
self,
config: LlamaConfig,
quant_config: Optional[QuantizationConfig] = None,
) -> None:
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(
[
LlamaDecoderLayer(
config, i, quant_config=quant_config, prefix=f"model.layers.{i}"
)
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,
input_embeds: torch.Tensor = None,
) -> torch.Tensor:
if input_embeds is None:
hidden_states = self.embed_tokens(input_ids)
else:
hidden_states = input_embeds
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 LlamaForCausalLM(nn.Module):
def __init__(
self,
config: LlamaConfig,
quant_config: Optional[QuantizationConfig] = None,
cache_config=None,
) -> None:
super().__init__()
self.config = config
self.quant_config = quant_config
self.torchao_config = global_server_args_dict["torchao_config"]
self.model = LlamaModel(config, quant_config=quant_config)
self.lm_head = ParallelLMHead(config.vocab_size, config.hidden_size)
self.logits_processor = LogitsProcessor(config)
self.pooler = Pooler(pooling_type=PoolingType.LAST, normalize=True)
@torch.no_grad()
def forward(
self,
input_ids: torch.Tensor,
positions: torch.Tensor,
forward_batch: ForwardBatch,
input_embeds: torch.Tensor = None,
get_embedding: bool = False,
) -> LogitsProcessorOutput:
hidden_states = self.model(input_ids, positions, forward_batch, input_embeds)
if not get_embedding:
return self.logits_processor(
input_ids, hidden_states, self.lm_head.weight, forward_batch
)
else:
return self.pooler(hidden_states, forward_batch)
def get_hidden_dim(self, module_name):
# return input_dim, output_dim
if module_name in ["q_proj", "o_proj", "qkv_proj"]:
return self.config.hidden_size, self.config.hidden_size
elif module_name in ["kv_proj"]:
return self.config.hidden_size, self.config.hidden_size // (
self.config.num_attention_heads // self.config.num_key_value_heads
)
elif module_name == "gate_up_proj":
return self.config.hidden_size, self.config.intermediate_size
elif module_name == "down_proj":
return self.config.intermediate_size, self.config.hidden_size
else:
raise NotImplementedError()
def get_module_name(self, name):
params_mapping = {
"q_proj": "qkv_proj",
"k_proj": "qkv_proj",
"v_proj": "qkv_proj",
"gate_proj": "gate_up_proj",
"up_proj": "gate_up_proj",
}
return params_mapping.get(name, name)
def get_module_name_from_weight_name(self, name):
stacked_params_mapping = [
# (param_name, shard_name, shard_id, num_shard)
("qkv_proj", "q_proj", "q", 3),
("qkv_proj", "k_proj", "k", 3),
("qkv_proj", "v_proj", "v", 3),
("gate_up_proj", "gate_proj", 0, 2),
("gate_up_proj", "up_proj", 1, 2),
]
for param_name, weight_name, shard_id, num_shard in stacked_params_mapping:
if weight_name in name:
return (
name.replace(weight_name, param_name)[: -len(".weight")],
num_shard,
)
return name[: -len(".weight")], 1
def get_num_params(self):
params_dict = dict(self.named_parameters())
return len(params_dict)
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 or "projector" 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 name.startswith("model.vision_tower") and name not in params_dict:
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
# Skip loading kv_scale from ckpts towards new design.
if name.endswith(".kv_scale") 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)
if (
hasattr(self.config, "tie_word_embeddings")
and self.config.tie_word_embeddings
and "lm_head.weight" in params_dict
):
# Tie output embedding layer to input embedding layer, to solve issues where lm_head.weight is missing
param = self.lm_head.weight
weight_loader = getattr(param, "weight_loader", default_weight_loader)
weight_loader(param, self.model.embed_tokens.weight)
apply_torchao_config_(self, params_dict, set(["proj.weight"]))
class Phi3ForCausalLM(LlamaForCausalLM):
pass
EntryClass = [LlamaForCausalLM, Phi3ForCausalLM]