# SPDX-License-Identifier: Apache-2.0 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project # Copyright 2024 The Qwen team. # Copyright 2023 The vLLM team. # 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 Qwen3 model compatible with HuggingFace weights.""" from collections.abc import Iterable from typing import Any import torch from torch import nn from transformers import Qwen3Config from vllm.attention.backends.abstract import AttentionType from vllm.attention.layer import Attention from vllm.compilation.decorators import support_torch_compile from vllm.config import CacheConfig, VllmConfig from vllm.distributed import get_pp_group, get_tensor_model_parallel_world_size from vllm.logger import init_logger from vllm.model_executor.layers.layernorm import RMSNorm from vllm.model_executor.layers.linear import QKVParallelLinear, RowParallelLinear from vllm.model_executor.layers.logits_processor import LogitsProcessor from vllm.model_executor.layers.quantization import QuantizationConfig from vllm.model_executor.layers.rotary_embedding import get_rope from vllm.model_executor.layers.vocab_parallel_embedding import ParallelLMHead from vllm.sequence import IntermediateTensors from vllm.transformers_utils.config import set_default_rope_theta from .interfaces import SupportsEagle3, SupportsLoRA, SupportsPP from .qwen2 import Qwen2MLP as Qwen3MLP from .qwen2 import Qwen2Model from .utils import AutoWeightsLoader, PPMissingLayer, extract_layer_index, maybe_prefix logger = init_logger(__name__) class Qwen3Attention(nn.Module): def __init__( self, hidden_size: int, num_heads: int, num_kv_heads: int, rope_parameters: dict, max_position: int = 4096 * 32, head_dim: int | None = None, rms_norm_eps: float = 1e-06, qkv_bias: bool = False, cache_config: CacheConfig | None = None, quant_config: QuantizationConfig | None = None, prefix: str = "", attn_type: str = AttentionType.DECODER, dual_chunk_attention_config: dict[str, Any] | None = None, ) -> 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) self.head_dim = head_dim or 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.dual_chunk_attention_config = dual_chunk_attention_config self.qkv_proj = QKVParallelLinear( hidden_size, self.head_dim, self.total_num_heads, self.total_num_kv_heads, bias=qkv_bias, 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, max_position=max_position, rope_parameters=rope_parameters, dual_chunk_attention_config=dual_chunk_attention_config, ) self.attn = Attention( self.num_heads, self.head_dim, self.scaling, num_kv_heads=self.num_kv_heads, cache_config=cache_config, quant_config=quant_config, prefix=f"{prefix}.attn", attn_type=attn_type, **{ "layer_idx": extract_layer_index(prefix), "dual_chunk_attention_config": dual_chunk_attention_config, } if dual_chunk_attention_config else {}, ) self.q_norm = RMSNorm(self.head_dim, eps=rms_norm_eps) self.k_norm = RMSNorm(self.head_dim, eps=rms_norm_eps) def forward( self, positions: torch.Tensor, hidden_states: torch.Tensor, ) -> torch.Tensor: qkv, _ = self.qkv_proj(hidden_states) q, k, v = qkv.split([self.q_size, self.kv_size, self.kv_size], dim=-1) # Add qk-norm q_by_head = q.view(*q.shape[:-1], q.shape[-1] // self.head_dim, self.head_dim) q_by_head = self.q_norm(q_by_head) q = q_by_head.view(q.shape) k_by_head = k.view(*k.shape[:-1], k.shape[-1] // self.head_dim, self.head_dim) k_by_head = self.k_norm(k_by_head) k = k_by_head.view(k.shape) q, k = self.rotary_emb(positions, q, k) attn_output = self.attn(q, k, v) output, _ = self.o_proj(attn_output) return output class Qwen3DecoderLayer(nn.Module): def __init__( self, config: Qwen3Config, cache_config: CacheConfig | None = None, quant_config: QuantizationConfig | None = None, prefix: str = "", ) -> None: super().__init__() self.hidden_size = config.hidden_size set_default_rope_theta(config, default_theta=1000000) dual_chunk_attention_config = getattr( config, "dual_chunk_attention_config", None ) # By default, Qwen3 uses causal attention as it is a decoder-only model. # You can override the HF config with `is_causal=False` to enable # bidirectional attention, which is used in some embedding models # (e.g. Alibaba-NLP/gte-Qwen3-7B-instruct) if getattr(config, "is_causal", True): attn_type = AttentionType.DECODER else: attn_type = AttentionType.ENCODER_ONLY self.self_attn = Qwen3Attention( hidden_size=self.hidden_size, num_heads=config.num_attention_heads, max_position=config.max_position_embeddings, num_kv_heads=config.num_key_value_heads, rms_norm_eps=config.rms_norm_eps, qkv_bias=getattr(config, "attention_bias", False), head_dim=getattr(config, "head_dim", None), cache_config=cache_config, quant_config=quant_config, rope_parameters=config.rope_parameters, prefix=f"{prefix}.self_attn", attn_type=attn_type, dual_chunk_attention_config=dual_chunk_attention_config, ) self.mlp = Qwen3MLP( 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, residual: torch.Tensor | None, ) -> 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, ) # Fully Connected hidden_states, residual = self.post_attention_layernorm(hidden_states, residual) hidden_states = self.mlp(hidden_states) return hidden_states, residual ALL_DECODER_LAYER_TYPES = { "attention": Qwen3DecoderLayer, } @support_torch_compile( dynamic_arg_dims={ "input_ids": 0, # positions is of shape (3, seq_len) if mrope is enabled for qwen2-vl, # otherwise (seq_len, ). "positions": -1, "intermediate_tensors": 0, "inputs_embeds": 0, } ) class Qwen3Model(Qwen2Model): def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""): super().__init__( vllm_config=vllm_config, prefix=prefix, decoder_layer_type=Qwen3DecoderLayer ) class Qwen3ForCausalLM(nn.Module, SupportsLoRA, SupportsPP, SupportsEagle3): packed_modules_mapping = { "qkv_proj": [ "q_proj", "k_proj", "v_proj", ], "gate_up_proj": [ "gate_proj", "up_proj", ], } def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""): super().__init__() config = vllm_config.model_config.hf_config quant_config = vllm_config.quant_config self.config = config self.quant_config = quant_config self.model = Qwen3Model( vllm_config=vllm_config, prefix=maybe_prefix(prefix, "model") ) if get_pp_group().is_last_rank: if 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=maybe_prefix(prefix, "lm_head"), ) else: self.lm_head = PPMissingLayer() self.logits_processor = LogitsProcessor(config.vocab_size) self.make_empty_intermediate_tensors = ( self.model.make_empty_intermediate_tensors ) def set_aux_hidden_state_layers(self, layers: tuple[int, ...]) -> None: self.model.aux_hidden_state_layers = layers def get_eagle3_aux_hidden_state_layers(self) -> tuple[int, ...]: num_layers = len(self.model.layers) return (2, num_layers // 2, num_layers - 3) def embed_input_ids(self, input_ids: torch.Tensor) -> torch.Tensor: return self.model.embed_input_ids(input_ids) def forward( self, input_ids: torch.Tensor, positions: torch.Tensor, intermediate_tensors: IntermediateTensors | None = None, inputs_embeds: torch.Tensor | None = None, ) -> torch.Tensor | IntermediateTensors: hidden_states = self.model( input_ids, positions, intermediate_tensors, inputs_embeds ) return hidden_states def compute_logits( self, hidden_states: torch.Tensor, ) -> torch.Tensor | None: logits = self.logits_processor(self.lm_head, hidden_states) return logits def load_weights(self, weights: Iterable[tuple[str, torch.Tensor]]) -> set[str]: loader = AutoWeightsLoader( self, skip_prefixes=(["lm_head."] if self.config.tie_word_embeddings else None), ) return loader.load_weights(weights)