Files
wehub-resource-sync ec436095dd
Book-CI / test (macos-latest) (push) Has been cancelled
Book-CI / test (ubuntu-latest) (push) Has been cancelled
Book-CI / test (windows-latest) (push) Has been cancelled
Release Fake Tag / publish (push) Has been cancelled
Deploy / deploy (macos-latest) (push) Has been cancelled
Deploy / deploy (ubuntu-latest) (push) Has been cancelled
Deploy / deploy (windows-latest) (push) Has been cancelled
Release to PyPI / Build & publish sglang-kt (push) Has been cancelled
Release to PyPI / Build kt-kernel (Python 3.11) (push) Has been cancelled
Release to PyPI / Build kt-kernel (Python 3.12) (push) Has been cancelled
Release to PyPI / Publish kt-kernel to PyPI (push) Has been cancelled
chore: import upstream snapshot with attribution
2026-07-13 13:30:03 +08:00

1287 lines
55 KiB
Python

# 🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨
# This file was automatically generated from src/transformers/models/qwen3_next/modular_qwen3_next.py.
# Do NOT edit this file manually as any edits will be overwritten by the generation of
# the file from the modular. If any change should be done, please apply the change to the
# modular_qwen3_next.py file directly. One of our CI enforces this.
# 🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨
# coding=utf-8
# Copyright 2025 The Qwen team, Alibaba Group and the HuggingFace Inc. team. All rights reserved.
#
# 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.
from typing import Any, Callable, Optional, Union
import torch
import torch.nn.functional as F
from torch import nn
from transformers.activations import ACT2FN
from transformers.cache_utils import Cache
from transformers.generation import GenerationMixin
from transformers.masking_utils import create_causal_mask
from transformers.modeling_flash_attention_utils import FlashAttentionKwargs
from transformers.modeling_layers import (
GenericForQuestionAnswering,
GenericForSequenceClassification,
GenericForTokenClassification,
GradientCheckpointingLayer,
)
from transformers.modeling_outputs import MoeCausalLMOutputWithPast, MoeModelOutputWithPast
from transformers.modeling_rope_utils import ROPE_INIT_FUNCTIONS, dynamic_rope_update
from transformers.modeling_utils import ALL_ATTENTION_FUNCTIONS, PreTrainedModel
from transformers.processing_utils import Unpack
from transformers.utils import TransformersKwargs, auto_docstring, can_return_tuple, logging
from transformers.utils.deprecation import deprecate_kwarg
from transformers.utils.generic import OutputRecorder, check_model_inputs
try:
from transformers.utils.import_utils import (
is_causal_conv1d_available,
is_flash_linear_attention_available,
)
except ImportError:
is_causal_conv1d_available = lambda: False
try:
from transformers.utils.import_utils import (
is_flash_linear_attention_available,
)
except ImportError:
is_flash_linear_attention_available = lambda: False
from .configuration_qwen3_next import Qwen3NextConfig
if is_causal_conv1d_available():
from causal_conv1d import causal_conv1d_fn, causal_conv1d_update
else:
causal_conv1d_update, causal_conv1d_fn = None, None
if is_flash_linear_attention_available():
from fla.modules import FusedRMSNormGated
from fla.ops.gated_delta_rule import chunk_gated_delta_rule, fused_recurrent_gated_delta_rule
else:
chunk_gated_delta_rule, fused_recurrent_gated_delta_rule = None, None
FusedRMSNormGated = None
logger = logging.get_logger(__name__)
class Qwen3NextRMSNormGated(nn.Module):
def __init__(self, hidden_size, eps=1e-6, **kwargs):
super().__init__()
self.weight = nn.Parameter(torch.ones(hidden_size))
self.variance_epsilon = eps
def forward(self, hidden_states, gate=None):
input_dtype = hidden_states.dtype
hidden_states = hidden_states.to(torch.float32)
variance = hidden_states.pow(2).mean(-1, keepdim=True)
# Norm before gate
hidden_states = hidden_states * torch.rsqrt(variance + self.variance_epsilon)
hidden_states = self.weight * hidden_states.to(input_dtype)
hidden_states = hidden_states * F.silu(gate.to(torch.float32))
return hidden_states.to(input_dtype)
class Qwen3NextDynamicCache:
"""
A dynamic cache that can handle both the attention cache (which has a seq_len dimension) and the linear attention
cache (which has a constant shape regardless of seq_len).
This cache has two sets of lists of tensors: `key_cache` and `value_cache` for attention cache and `conv_states`
and `ssm_states` for gated deltanet cache. Each of these lists has `num_layers` tensors. The expected shape for each tensor
For attention layers, `key_cache` and `value_cache` have a shape of `(batch_size, num_heads, seq_len, head_dim)`,
while `conv_states` and `ssm_states` have a shape of `(batch_size, 0)` (empty tensors).
For linear attention layers, `key_cache` and `value_cache` have a shape of `(batch_size, 0)` (empty tensors),
while `conv_states` represents the convolution state and has a shape of `(batch_size, d_inner, d_conv)`,
and `recurrent_states` represents the recurrent state and has a shape of `(batch_size, d_inner, d_state)`.
"""
is_compileable = False
def __init__(self, config: Qwen3NextConfig):
super().__init__()
self.layer_types = config.layer_types
self.transformer_layers = [
i for i in range(config.num_hidden_layers) if self.layer_types[i] == "full_attention"
]
self.last_linear_layer = len(self.layer_types) - 1 - self.layer_types[::-1].index("linear_attention")
# Initialize everything to None -> will be lazy initialized to allow multi-gpu (device_map) inference
self.conv_states = [None for _ in range(config.num_hidden_layers)]
self.recurrent_states = [None for _ in range(config.num_hidden_layers)]
self.key_cache = [None for _ in range(config.num_hidden_layers)]
self.value_cache = [None for _ in range(config.num_hidden_layers)]
def __len__(self):
return len(self.layer_types)
def __getitem__(self, layer_idx: int) -> tuple[torch.Tensor, torch.Tensor]:
return self.key_cache[layer_idx], self.value_cache[layer_idx]
def update(
self,
key_states: torch.Tensor,
value_states: torch.Tensor,
layer_idx: int,
cache_kwargs: Optional[dict[str, Any]] = None,
) -> tuple[torch.Tensor, torch.Tensor]:
if self.key_cache[layer_idx] is None:
self.key_cache[layer_idx] = key_states
self.value_cache[layer_idx] = value_states
else:
self.key_cache[layer_idx] = torch.cat([self.key_cache[layer_idx], key_states], dim=2)
self.value_cache[layer_idx] = torch.cat([self.value_cache[layer_idx], value_states], dim=2)
return self.key_cache[layer_idx], self.value_cache[layer_idx]
def reorder_cache(self, beam_idx: torch.LongTensor):
"""Reorders the cache for beam search, given the selected beam indices."""
for layer_idx in range(len(self.key_cache)):
if self.key_cache[layer_idx] is not None:
device = self.key_cache[layer_idx].device
beam_idx = beam_idx.to(device)
self.key_cache[layer_idx] = self.key_cache[layer_idx].index_select(0, beam_idx)
self.value_cache[layer_idx] = self.value_cache[layer_idx].index_select(0, beam_idx)
if self.conv_states[layer_idx] is not None:
device = self.conv_states[layer_idx].device
beam_idx = beam_idx.to(device)
self.conv_states[layer_idx] = self.conv_states[layer_idx].index_select(0, beam_idx)
self.recurrent_states[layer_idx] = self.recurrent_states[layer_idx].index_select(0, beam_idx)
def get_seq_length(self, layer_idx: Optional[int] = 0) -> int:
"""Returns the sequence length of the cached states. A layer index can be optionally passed."""
# take any layer that contains cache and not empty tensor
layer_idx = self.transformer_layers[0] if layer_idx not in self.transformer_layers else layer_idx
if len(self.key_cache) <= layer_idx or self.key_cache[layer_idx] is None:
return 0
return self.key_cache[layer_idx].shape[-2]
def get_mask_sizes(self, cache_position: torch.Tensor, layer_idx: int) -> tuple[int, int]:
"""
Return a tuple (kv_length, kv_offset) corresponding to the length and offset that will be returned for
the given layer at `layer_idx`.
The masks are then prepared according to the given lengths (kv_length, kv_offset) and patterns for each layer.
"""
kv_offset = 0
query_length = cache_position.shape[0]
past_seen_tokens = self.get_seq_length(layer_idx)
kv_length = query_length + past_seen_tokens
return kv_length, kv_offset
@property
def has_previous_state(self):
"""We have a previous state if the last linear (conv) layer was already updated."""
return self.conv_states[self.last_linear_layer] is not None
class Qwen3NextRotaryEmbedding(nn.Module):
inv_freq: torch.Tensor # fix linting for `register_buffer`
def __init__(self, config: Qwen3NextConfig, device=None):
super().__init__()
# BC: "rope_type" was originally "type"
if hasattr(config, "rope_scaling") and isinstance(config.rope_scaling, dict):
self.rope_type = config.rope_scaling.get("rope_type", config.rope_scaling.get("type"))
else:
self.rope_type = "default"
self.max_seq_len_cached = config.max_position_embeddings
self.original_max_seq_len = config.max_position_embeddings
self.config = config
self.rope_init_fn = ROPE_INIT_FUNCTIONS[self.rope_type]
inv_freq, self.attention_scaling = self.rope_init_fn(self.config, device)
self.register_buffer("inv_freq", inv_freq, persistent=False)
self.original_inv_freq = self.inv_freq
@torch.no_grad()
@dynamic_rope_update # power user: used with advanced RoPE types (e.g. dynamic rope)
def forward(self, x, position_ids):
inv_freq_expanded = self.inv_freq[None, :, None].float().expand(position_ids.shape[0], -1, 1).to(x.device)
position_ids_expanded = position_ids[:, None, :].float()
device_type = x.device.type if isinstance(x.device.type, str) and x.device.type != "mps" else "cpu"
with torch.autocast(device_type=device_type, enabled=False): # Force float32
freqs = (inv_freq_expanded.float() @ position_ids_expanded.float()).transpose(1, 2)
emb = torch.cat((freqs, freqs), dim=-1)
cos = emb.cos() * self.attention_scaling
sin = emb.sin() * self.attention_scaling
return cos.to(dtype=x.dtype), sin.to(dtype=x.dtype)
class Qwen3NextRMSNorm(nn.Module):
def __init__(self, dim: int, eps: float = 1e-6):
super().__init__()
self.hidden_size = dim
self.variance_epsilon = eps
self.eps = eps
self.weight = nn.Parameter(torch.zeros(dim))
def _norm(self, x):
return x * torch.rsqrt(x.pow(2).mean(-1, keepdim=True) + self.eps)
def forward(self, x):
output = self._norm(x.float())
# Llama does x.to(float16) * w whilst Qwen3Next is (x * w).to(float16)
# See https://github.com/huggingface/transformers/pull/29402
output = output * (1.0 + self.weight.float())
return output.type_as(x)
def extra_repr(self):
return f"{tuple(self.weight.shape)}, eps={self.eps}"
def rotate_half(x):
"""Rotates half the hidden dims of the input."""
x1 = x[..., : x.shape[-1] // 2]
x2 = x[..., x.shape[-1] // 2 :]
return torch.cat((-x2, x1), dim=-1)
# Adapted from transformers.models.glm.modular_glm.apply_rotary_pos_emb
def apply_rotary_pos_emb(q, k, cos, sin, position_ids=None, unsqueeze_dim=1):
"""Applies Rotary Position Embedding to the query and key tensors.
Removes the interleaving of cos and sin from GLM
Args:
q (`torch.Tensor`): The query tensor.
k (`torch.Tensor`): The key tensor.
cos (`torch.Tensor`): The cosine part of the rotary embedding.
sin (`torch.Tensor`): The sine part of the rotary embedding.
position_ids (`torch.Tensor`, *optional*):
Deprecated and unused.
unsqueeze_dim (`int`, *optional*, defaults to 1):
The 'unsqueeze_dim' argument specifies the dimension along which to unsqueeze cos[position_ids] and
sin[position_ids] so that they can be properly broadcasted to the dimensions of q and k. For example, note
that cos[position_ids] and sin[position_ids] have the shape [batch_size, seq_len, head_dim]. Then, if q and
k have the shape [batch_size, heads, seq_len, head_dim], then setting unsqueeze_dim=1 makes
cos[position_ids] and sin[position_ids] broadcastable to the shapes of q and k. Similarly, if q and k have
the shape [batch_size, seq_len, heads, head_dim], then set unsqueeze_dim=2.
Returns:
`tuple(torch.Tensor)` comprising of the query and key tensors rotated using the Rotary Position Embedding.
"""
cos = cos.unsqueeze(unsqueeze_dim)
sin = sin.unsqueeze(unsqueeze_dim)
# Keep half or full tensor for later concatenation
rotary_dim = cos.shape[-1]
q_rot, q_pass = q[..., :rotary_dim], q[..., rotary_dim:]
k_rot, k_pass = k[..., :rotary_dim], k[..., rotary_dim:]
# Apply rotary embeddings on the first half or full tensor
q_embed = (q_rot * cos) + (rotate_half(q_rot) * sin)
k_embed = (k_rot * cos) + (rotate_half(k_rot) * sin)
# Concatenate back to full shape
q_embed = torch.cat([q_embed, q_pass], dim=-1)
k_embed = torch.cat([k_embed, k_pass], dim=-1)
return q_embed, k_embed
def repeat_kv(hidden_states: torch.Tensor, n_rep: int) -> torch.Tensor:
"""
This is the equivalent of torch.repeat_interleave(x, dim=1, repeats=n_rep). The hidden states go from (batch,
num_key_value_heads, seqlen, head_dim) to (batch, num_attention_heads, seqlen, head_dim)
"""
batch, num_key_value_heads, slen, head_dim = hidden_states.shape
if n_rep == 1:
return hidden_states
hidden_states = hidden_states[:, :, None, :, :].expand(batch, num_key_value_heads, n_rep, slen, head_dim)
return hidden_states.reshape(batch, num_key_value_heads * n_rep, slen, head_dim)
def eager_attention_forward(
module: nn.Module,
query: torch.Tensor,
key: torch.Tensor,
value: torch.Tensor,
attention_mask: Optional[torch.Tensor],
scaling: float,
dropout: float = 0.0,
**kwargs: Unpack[TransformersKwargs],
):
key_states = repeat_kv(key, module.num_key_value_groups)
value_states = repeat_kv(value, module.num_key_value_groups)
attn_weights = torch.matmul(query, key_states.transpose(2, 3)) * scaling
if attention_mask is not None:
causal_mask = attention_mask[:, :, :, : key_states.shape[-2]]
attn_weights = attn_weights + causal_mask
attn_weights = nn.functional.softmax(attn_weights, dim=-1, dtype=torch.float32).to(query.dtype)
attn_weights = nn.functional.dropout(attn_weights, p=dropout, training=module.training)
attn_output = torch.matmul(attn_weights, value_states)
attn_output = attn_output.transpose(1, 2).contiguous()
return attn_output, attn_weights
class Qwen3NextAttention(nn.Module):
"""Multi-headed attention from 'Attention Is All You Need' paper"""
def __init__(self, config: Qwen3NextConfig, layer_idx: int):
super().__init__()
self.config = config
self.layer_idx = layer_idx
self.head_dim = getattr(config, "head_dim", config.hidden_size // config.num_attention_heads)
self.num_attention_heads = config.num_attention_heads
self.num_key_value_heads = config.num_key_value_heads
self.num_key_value_groups = config.num_attention_heads // config.num_key_value_heads
self.scaling = self.head_dim**-0.5
self.attention_dropout = config.attention_dropout
self.is_causal = True
self.q_proj = nn.Linear(
config.hidden_size, config.num_attention_heads * self.head_dim * 2, bias=config.attention_bias
)
self.k_proj = nn.Linear(
config.hidden_size, config.num_key_value_heads * self.head_dim, bias=config.attention_bias
)
self.v_proj = nn.Linear(
config.hidden_size, config.num_key_value_heads * self.head_dim, bias=config.attention_bias
)
self.o_proj = nn.Linear(
config.num_attention_heads * self.head_dim, config.hidden_size, bias=config.attention_bias
)
self.q_norm = Qwen3NextRMSNorm(self.head_dim, eps=config.rms_norm_eps) # unlike olmo, only on the head dim!
self.k_norm = Qwen3NextRMSNorm(
self.head_dim, eps=config.rms_norm_eps
) # thus post q_norm does not need reshape
@deprecate_kwarg("past_key_value", new_name="past_key_values", version="4.58")
def forward(
self,
hidden_states: torch.Tensor,
position_embeddings: tuple[torch.Tensor, torch.Tensor],
attention_mask: Optional[torch.Tensor],
past_key_values: Optional[Cache] = None,
cache_position: Optional[torch.LongTensor] = None,
**kwargs: Unpack[FlashAttentionKwargs],
) -> tuple[torch.Tensor, Optional[torch.Tensor]]:
input_shape = hidden_states.shape[:-1]
hidden_shape = (*input_shape, -1, self.head_dim)
query_states, gate = torch.chunk(
self.q_proj(hidden_states).view(*input_shape, -1, self.head_dim * 2), 2, dim=-1
)
gate = gate.reshape(*input_shape, -1)
query_states = self.q_norm(query_states.view(hidden_shape)).transpose(1, 2)
key_states = self.k_norm(self.k_proj(hidden_states).view(hidden_shape)).transpose(1, 2)
value_states = self.v_proj(hidden_states).view(hidden_shape).transpose(1, 2)
cos, sin = position_embeddings
query_states, key_states = apply_rotary_pos_emb(query_states, key_states, cos, sin)
if past_key_values is not None:
# sin and cos are specific to RoPE models; cache_position needed for the static cache
cache_kwargs = {"sin": sin, "cos": cos, "cache_position": cache_position}
key_states, value_states = past_key_values.update(key_states, value_states, self.layer_idx, cache_kwargs)
attention_interface: Callable = eager_attention_forward
if self.config._attn_implementation != "eager":
attention_interface = ALL_ATTENTION_FUNCTIONS[self.config._attn_implementation]
attn_output, attn_weights = attention_interface(
self,
query_states,
key_states,
value_states,
attention_mask,
dropout=0.0 if not self.training else self.attention_dropout,
scaling=self.scaling,
**kwargs,
)
attn_output = attn_output.reshape(*input_shape, -1).contiguous()
attn_output = attn_output * torch.sigmoid(gate)
attn_output = self.o_proj(attn_output)
return attn_output, attn_weights
def apply_mask_to_padding_states(hidden_states, attention_mask):
"""
Tunes out the hidden states for padding tokens, see https://github.com/state-spaces/mamba/issues/66
"""
if attention_mask is not None and attention_mask.shape[1] > 1 and attention_mask.shape[0] > 1:
dtype = hidden_states.dtype
hidden_states = (hidden_states * attention_mask[:, :, None]).to(dtype)
return hidden_states
is_fast_path_available = all(
(causal_conv1d_fn, causal_conv1d_update, chunk_gated_delta_rule, fused_recurrent_gated_delta_rule)
)
def torch_causal_conv1d_update(
hidden_states,
conv_state,
weight,
bias=None,
activation=None,
):
_, hidden_size, seq_len = hidden_states.shape
state_len = conv_state.shape[-1]
hidden_states_new = torch.cat([conv_state, hidden_states], dim=-1).to(weight.dtype)
conv_state.copy_(hidden_states_new[:, :, -state_len:])
out = F.conv1d(hidden_states_new, weight.unsqueeze(1), bias, padding=0, groups=hidden_size)
out = F.silu(out[:, :, -seq_len:])
out = out.to(hidden_states.dtype)
return out
def torch_chunk_gated_delta_rule(
query,
key,
value,
g,
beta,
chunk_size=64,
initial_state=None,
output_final_state=False,
use_qk_l2norm_in_kernel=False,
):
initial_dtype = query.dtype
if use_qk_l2norm_in_kernel:
query = F.normalize(query, p=2, dim=-1)
key = F.normalize(key, p=2, dim=-1)
query, key, value, beta, g = [
x.transpose(1, 2).contiguous().to(torch.float32) for x in (query, key, value, beta, g)
]
batch_size, sequence_length, num_heads, k_head_dim = key.shape
v_head_dim = value.shape[-1]
pad_size = (chunk_size - num_heads % chunk_size) % chunk_size
query = F.pad(query, (0, 0, 0, pad_size))
key = F.pad(key, (0, 0, 0, pad_size))
value = F.pad(value, (0, 0, 0, pad_size))
beta = F.pad(beta, (0, pad_size))
g = F.pad(g, (0, pad_size))
tot_heads = num_heads + pad_size
scale = 1 / (query.shape[-1] ** 0.5)
query = query * scale
v_beta = value * beta.unsqueeze(-1)
k_beta = key * beta.unsqueeze(-1)
# reshape to chunks
query, key, value, k_beta, v_beta = [
x.reshape(x.shape[0], x.shape[1], -1, chunk_size, x.shape[-1]) for x in (query, key, value, k_beta, v_beta)
]
g = g.reshape(g.shape[0], g.shape[1], -1, chunk_size)
mask = torch.triu(torch.ones(chunk_size, chunk_size, dtype=torch.bool, device=query.device), diagonal=0)
# chunk decay
g = g.cumsum(dim=-1)
decay_mask = ((g.unsqueeze(-1) - g.unsqueeze(-2)).tril().exp().float()).tril()
attn = -((k_beta @ key.transpose(-1, -2)) * decay_mask).masked_fill(mask, 0)
for i in range(1, chunk_size):
row = attn[..., i, :i].clone()
sub = attn[..., :i, :i].clone()
attn[..., i, :i] = row + (row.unsqueeze(-1) * sub).sum(-2)
attn = attn + torch.eye(chunk_size, dtype=attn.dtype, device=attn.device)
value = attn @ v_beta
k_cumdecay = attn @ (k_beta * g.exp().unsqueeze(-1))
last_recurrent_state = (
torch.zeros(batch_size, sequence_length, k_head_dim, v_head_dim).to(value)
if initial_state is None
else initial_state.to(value)
)
core_attn_out = torch.zeros_like(value)
mask = torch.triu(torch.ones(chunk_size, chunk_size, dtype=torch.bool, device=query.device), diagonal=1)
# for each chunk
for i in range(0, tot_heads // chunk_size):
q_i, k_i, v_i = query[:, :, i], key[:, :, i], value[:, :, i]
attn = (q_i @ k_i.transpose(-1, -2) * decay_mask[:, :, i]).masked_fill_(mask, 0)
v_prime = (k_cumdecay[:, :, i]) @ last_recurrent_state
v_new = v_i - v_prime
attn_inter = (q_i * g[:, :, i, :, None].exp()) @ last_recurrent_state
core_attn_out[:, :, i] = attn_inter + attn @ v_new
last_recurrent_state = (
last_recurrent_state * g[:, :, i, -1, None, None].exp()
+ (k_i * (g[:, :, i, -1, None] - g[:, :, i]).exp()[..., None]).transpose(-1, -2) @ v_new
)
if not output_final_state:
last_recurrent_state = None
core_attn_out = core_attn_out.reshape(core_attn_out.shape[0], core_attn_out.shape[1], -1, core_attn_out.shape[-1])
core_attn_out = core_attn_out[:, :, :num_heads]
core_attn_out = core_attn_out.transpose(1, 2).contiguous().to(initial_dtype)
return core_attn_out, last_recurrent_state
def torch_recurrent_gated_delta_rule(
query, key, value, g, beta, initial_state, output_final_state, use_qk_l2norm_in_kernel=False
):
initial_dtype = query.dtype
if use_qk_l2norm_in_kernel:
query = F.normalize(query, p=2, dim=-1)
key = F.normalize(key, p=2, dim=-1)
query, key, value, beta, g = [
x.transpose(1, 2).contiguous().to(torch.float32) for x in (query, key, value, beta, g)
]
batch_size, sequence_length, num_heads, k_head_dim = key.shape
v_head_dim = value.shape[-1]
scale = 1 / (query.shape[-1] ** 0.5)
query = query * scale
core_attn_out = torch.zeros(batch_size, sequence_length, num_heads, v_head_dim).to(value)
last_recurrent_state = (
torch.zeros(batch_size, sequence_length, k_head_dim, v_head_dim).to(value)
if initial_state is None
else initial_state.to(value)
)
for i in range(num_heads):
q_t = query[:, :, i]
k_t = key[:, :, i]
v_t = value[:, :, i]
g_t = g[:, :, i].exp().unsqueeze(-1).unsqueeze(-1)
beta_t = beta[:, :, i].unsqueeze(-1)
last_recurrent_state = last_recurrent_state * g_t
kv_mem = (last_recurrent_state * k_t.unsqueeze(-1)).sum(dim=-2)
delta = (v_t - kv_mem) * beta_t
last_recurrent_state = last_recurrent_state + k_t.unsqueeze(-1) * delta.unsqueeze(-2)
core_attn_out[:, :, i] = (last_recurrent_state * q_t.unsqueeze(-1)).sum(dim=-2)
if not output_final_state:
last_recurrent_state = None
core_attn_out = core_attn_out.transpose(1, 2).contiguous().to(initial_dtype)
return core_attn_out, last_recurrent_state
class Qwen3NextGatedDeltaNet(nn.Module):
def __init__(self, config: Qwen3NextConfig, layer_idx: int):
super().__init__()
self.hidden_size = config.hidden_size
self.num_v_heads = config.linear_num_value_heads
self.num_k_heads = config.linear_num_key_heads
self.head_k_dim = config.linear_key_head_dim
self.head_v_dim = config.linear_value_head_dim
self.key_dim = self.head_k_dim * self.num_k_heads
self.value_dim = self.head_v_dim * self.num_v_heads
self.conv_kernel_size = config.linear_conv_kernel_dim
self.layer_idx = layer_idx
self.activation = config.hidden_act
self.act = ACT2FN[config.hidden_act]
self.layer_norm_epsilon = config.rms_norm_eps
self.config = config
# QKV
self.conv_dim = self.key_dim * 2 + self.value_dim
self.conv1d = nn.Conv1d(
in_channels=self.conv_dim,
out_channels=self.conv_dim,
bias=False,
kernel_size=self.conv_kernel_size,
groups=self.conv_dim,
padding=self.conv_kernel_size - 1,
)
# projection of the input hidden states
projection_size_qkvz = self.key_dim * 2 + self.value_dim * 2
projection_size_ba = self.num_v_heads * 2
self.in_proj_qkvz = nn.Linear(self.hidden_size, projection_size_qkvz, bias=False)
self.in_proj_ba = nn.Linear(self.hidden_size, projection_size_ba, bias=False)
# time step projection (discretization)
# instantiate once and copy inv_dt in init_weights of PretrainedModel
self.dt_bias = nn.Parameter(torch.ones(self.num_v_heads))
A = torch.empty(self.num_v_heads).uniform_(0, 16)
self.A_log = nn.Parameter(torch.log(A))
self.norm = (
Qwen3NextRMSNormGated(self.head_v_dim, eps=self.layer_norm_epsilon)
if FusedRMSNormGated is None
else FusedRMSNormGated(
self.head_v_dim,
eps=self.layer_norm_epsilon,
activation=self.activation,
device=torch.cuda.current_device(),
dtype=config.dtype if config.dtype is not None else torch.get_current_dtype(),
)
)
self.out_proj = nn.Linear(self.value_dim, self.hidden_size, bias=False)
self.causal_conv1d_fn = causal_conv1d_fn
self.causal_conv1d_update = causal_conv1d_update or torch_causal_conv1d_update
self.chunk_gated_delta_rule = chunk_gated_delta_rule or torch_chunk_gated_delta_rule
self.recurrent_gated_delta_rule = fused_recurrent_gated_delta_rule or torch_recurrent_gated_delta_rule
if not is_fast_path_available:
logger.warning_once(
"The fast path is not available because one of the required library is not installed. Falling back to "
"torch implementation. To install follow https://github.com/fla-org/flash-linear-attention#installation and"
" https://github.com/Dao-AILab/causal-conv1d"
)
def fix_query_key_value_ordering(self, mixed_qkvz, mixed_ba):
"""
Derives `query`, `key` and `value` tensors from `mixed_qkvz` and `mixed_ba`.
"""
new_tensor_shape_qkvz = mixed_qkvz.size()[:-1] + (
self.num_k_heads,
2 * self.head_k_dim + 2 * self.head_v_dim * self.num_v_heads // self.num_k_heads,
)
new_tensor_shape_ba = mixed_ba.size()[:-1] + (self.num_k_heads, 2 * self.num_v_heads // self.num_k_heads)
mixed_qkvz = mixed_qkvz.view(*new_tensor_shape_qkvz)
mixed_ba = mixed_ba.view(*new_tensor_shape_ba)
split_arg_list_qkvz = [
self.head_k_dim,
self.head_k_dim,
(self.num_v_heads // self.num_k_heads * self.head_v_dim),
(self.num_v_heads // self.num_k_heads * self.head_v_dim),
]
split_arg_list_ba = [self.num_v_heads // self.num_k_heads, self.num_v_heads // self.num_k_heads]
query, key, value, z = torch.split(mixed_qkvz, split_arg_list_qkvz, dim=3)
b, a = torch.split(mixed_ba, split_arg_list_ba, dim=3)
# [b, sq, ng, np/ng * hn] -> [b, sq, np, hn]
value = value.reshape(value.size(0), value.size(1), -1, self.head_v_dim)
z = z.reshape(z.size(0), z.size(1), -1, self.head_v_dim)
b = b.reshape(b.size(0), b.size(1), self.num_v_heads)
a = a.reshape(a.size(0), a.size(1), self.num_v_heads)
return query, key, value, z, b, a
def forward(
self,
hidden_states: torch.Tensor,
cache_params: Optional[Qwen3NextDynamicCache] = None,
cache_position: Optional[torch.LongTensor] = None,
attention_mask: Optional[torch.Tensor] = None,
):
hidden_states = apply_mask_to_padding_states(hidden_states, attention_mask)
# Set up dimensions for reshapes later
batch_size, seq_len, _ = hidden_states.shape
use_precomputed_states = (
cache_params is not None
and cache_params.has_previous_state
and seq_len == 1
and cache_position is not None
)
# getting projected states from cache if it exists
if cache_params is not None:
conv_state = cache_params.conv_states[self.layer_idx]
recurrent_state = cache_params.recurrent_states[self.layer_idx]
projected_states_qkvz = self.in_proj_qkvz(hidden_states)
projected_states_ba = self.in_proj_ba(hidden_states)
query, key, value, z, b, a = self.fix_query_key_value_ordering(projected_states_qkvz, projected_states_ba)
query, key, value = (x.reshape(x.shape[0], x.shape[1], -1) for x in (query, key, value))
mixed_qkv = torch.cat((query, key, value), dim=-1)
mixed_qkv = mixed_qkv.transpose(1, 2)
if use_precomputed_states:
# 2. Convolution sequence transformation
# NOTE: the conv state is updated in `causal_conv1d_update`
mixed_qkv = self.causal_conv1d_update(
mixed_qkv,
conv_state,
self.conv1d.weight.squeeze(1),
self.conv1d.bias,
self.activation,
)
else:
if cache_params is not None:
conv_state = F.pad(mixed_qkv, (self.conv_kernel_size - mixed_qkv.shape[-1], 0))
cache_params.conv_states[self.layer_idx] = conv_state
if self.causal_conv1d_fn is not None:
mixed_qkv = self.causal_conv1d_fn(
x=mixed_qkv,
weight=self.conv1d.weight.squeeze(1),
bias=self.conv1d.bias,
activation=self.activation,
seq_idx=None,
)
else:
mixed_qkv = F.silu(self.conv1d(mixed_qkv)[:, :, :seq_len])
mixed_qkv = mixed_qkv.transpose(1, 2)
query, key, value = torch.split(
mixed_qkv,
[
self.key_dim,
self.key_dim,
self.value_dim,
],
dim=-1,
)
query = query.reshape(query.shape[0], query.shape[1], -1, self.head_k_dim)
key = key.reshape(key.shape[0], key.shape[1], -1, self.head_k_dim)
value = value.reshape(value.shape[0], value.shape[1], -1, self.head_v_dim)
beta = b.sigmoid()
# If the model is loaded in fp16, without the .float() here, A might be -inf
g = -self.A_log.float().exp() * F.softplus(a.float() + self.dt_bias)
if self.num_v_heads // self.num_k_heads > 1:
query = query.repeat_interleave(self.num_v_heads // self.num_k_heads, dim=2)
key = key.repeat_interleave(self.num_v_heads // self.num_k_heads, dim=2)
if not use_precomputed_states:
core_attn_out, last_recurrent_state = self.chunk_gated_delta_rule(
query,
key,
value,
g=g,
beta=beta,
initial_state=None,
output_final_state=cache_params is not None,
use_qk_l2norm_in_kernel=True,
)
else:
core_attn_out, last_recurrent_state = self.recurrent_gated_delta_rule(
query,
key,
value,
g=g,
beta=beta,
initial_state=recurrent_state,
output_final_state=cache_params is not None,
use_qk_l2norm_in_kernel=True,
)
# Update cache
if cache_params is not None:
cache_params.recurrent_states[self.layer_idx] = last_recurrent_state
z_shape_og = z.shape
# reshape input data into 2D tensor
core_attn_out = core_attn_out.reshape(-1, core_attn_out.shape[-1])
z = z.reshape(-1, z.shape[-1])
core_attn_out = self.norm(core_attn_out, z)
core_attn_out = core_attn_out.reshape(z_shape_og)
core_attn_out = core_attn_out.reshape(core_attn_out.shape[0], core_attn_out.shape[1], -1)
output = self.out_proj(core_attn_out)
return output
class Qwen3NextMLP(nn.Module):
def __init__(self, config, intermediate_size=None):
super().__init__()
self.config = config
self.hidden_size = config.hidden_size
self.intermediate_size = intermediate_size if intermediate_size is not None else config.intermediate_size
self.gate_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=False)
self.up_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=False)
self.down_proj = nn.Linear(self.intermediate_size, self.hidden_size, bias=False)
self.act_fn = ACT2FN[config.hidden_act]
def forward(self, x):
down_proj = self.down_proj(self.act_fn(self.gate_proj(x)) * self.up_proj(x))
return down_proj
class Qwen3NextSparseMoeBlock(nn.Module):
def __init__(self, config):
super().__init__()
self.num_experts = config.num_experts
self.top_k = config.num_experts_per_tok
self.norm_topk_prob = config.norm_topk_prob
# gating
self.gate = nn.Linear(config.hidden_size, config.num_experts, bias=False)
self.experts = nn.ModuleList(
[Qwen3NextMLP(config, intermediate_size=config.moe_intermediate_size) for _ in range(self.num_experts)]
)
self.shared_expert = Qwen3NextMLP(config, intermediate_size=config.shared_expert_intermediate_size)
self.shared_expert_gate = torch.nn.Linear(config.hidden_size, 1, bias=False)
def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
""" """
batch_size, sequence_length, hidden_dim = hidden_states.shape
hidden_states = hidden_states.view(-1, hidden_dim)
# router_logits: (batch * sequence_length, n_experts)
router_logits = self.gate(hidden_states)
routing_weights = F.softmax(router_logits, dim=1, dtype=torch.float)
routing_weights, selected_experts = torch.topk(routing_weights, self.top_k, dim=-1)
if self.norm_topk_prob:
routing_weights /= routing_weights.sum(dim=-1, keepdim=True)
# we cast back to the input dtype
routing_weights = routing_weights.to(hidden_states.dtype)
final_hidden_states = torch.zeros(
(batch_size * sequence_length, hidden_dim), dtype=hidden_states.dtype, device=hidden_states.device
)
# One hot encode the selected experts to create an expert mask
# this will be used to easily index which expert is going to be sollicitated
expert_mask = torch.nn.functional.one_hot(selected_experts, num_classes=self.num_experts).permute(2, 1, 0)
# Loop over all available experts in the model and perform the computation on each expert
expert_hit = torch.greater(expert_mask.sum(dim=(-1, -2)), 0).nonzero()
for expert_idx in expert_hit:
expert_layer = self.experts[expert_idx]
idx, top_x = torch.where(expert_mask[expert_idx].squeeze(0))
# Index the correct hidden states and compute the expert hidden state for
# the current expert. We need to make sure to multiply the output hidden
# states by `routing_weights` on the corresponding tokens (top-1 and top-2)
current_state = hidden_states[None, top_x].reshape(-1, hidden_dim)
current_hidden_states = expert_layer(current_state) * routing_weights[top_x, idx, None]
# However `index_add_` only support torch tensors for indexing so we'll use
# the `top_x` tensor here.
final_hidden_states.index_add_(0, top_x, current_hidden_states.to(hidden_states.dtype))
shared_expert_output = self.shared_expert(hidden_states)
shared_expert_output = F.sigmoid(self.shared_expert_gate(hidden_states)) * shared_expert_output
final_hidden_states = final_hidden_states + shared_expert_output
final_hidden_states = final_hidden_states.reshape(batch_size, sequence_length, hidden_dim)
return final_hidden_states, router_logits
class Qwen3NextDecoderLayer(GradientCheckpointingLayer):
def __init__(self, config: Qwen3NextConfig, layer_idx: int):
super().__init__()
self.hidden_size = config.hidden_size
# token mixer
self.layer_type = config.layer_types[layer_idx]
if self.layer_type == "linear_attention":
self.linear_attn = Qwen3NextGatedDeltaNet(config, layer_idx)
elif self.layer_type == "full_attention":
self.self_attn = Qwen3NextAttention(config, layer_idx)
if (layer_idx not in config.mlp_only_layers) and (
config.num_experts > 0 and (layer_idx + 1) % config.decoder_sparse_step == 0
):
self.mlp = Qwen3NextSparseMoeBlock(config)
else:
self.mlp = Qwen3NextMLP(config, intermediate_size=config.intermediate_size)
self.input_layernorm = Qwen3NextRMSNorm(config.hidden_size, eps=config.rms_norm_eps)
self.post_attention_layernorm = Qwen3NextRMSNorm(config.hidden_size, eps=config.rms_norm_eps)
@deprecate_kwarg("past_key_value", new_name="past_key_values", version="4.58")
def forward(
self,
hidden_states: torch.Tensor,
position_embeddings: tuple[torch.Tensor, torch.Tensor],
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.LongTensor] = None,
past_key_values: Optional[tuple[torch.Tensor]] = None,
cache_position: Optional[torch.LongTensor] = None,
**kwargs: Unpack[FlashAttentionKwargs],
) -> torch.FloatTensor:
"""
Args:
hidden_states (`torch.FloatTensor`): input to the layer of shape `(batch, seq_len, embed_dim)`
attention_mask (`torch.FloatTensor`, *optional*): attention mask of size
`(batch, sequence_length)` where padding elements are indicated by 0.
output_attentions (`bool`, *optional*):
Whether or not to return the attentions tensors of all attention layers. See `attentions` under
returned tensors for more detail.
output_router_logits (`bool`, *optional*):
Whether or not to return the logits of all the routers. They are useful for computing the router loss,
and should not be returned during inference.
use_cache (`bool`, *optional*):
If set to `True`, `past_key_values` key value states are returned and can be used to speed up decoding
(see `past_key_values`).
past_key_values (`Tuple(torch.FloatTensor)`, *optional*): cached past key and value projection states
cache_position (`torch.LongTensor` of shape `(sequence_length)`, *optional*):
Indices depicting the position of the input sequence tokens in the sequence.
position_embeddings (`tuple[torch.FloatTensor, torch.FloatTensor]`, *optional*):
Tuple containing the cosine and sine positional embeddings of shape `(batch_size, seq_len, head_dim)`,
with `head_dim` being the embedding dimension of each attention head.
kwargs (`dict`, *optional*):
Arbitrary kwargs to be ignored, used for FSDP and other methods that injects code
into the model
"""
residual = hidden_states
hidden_states = self.input_layernorm(hidden_states)
# Token Mixer
if self.layer_type == "linear_attention":
hidden_states = self.linear_attn(
hidden_states=hidden_states,
cache_params=past_key_values,
cache_position=cache_position,
attention_mask=attention_mask,
)
elif self.layer_type == "full_attention":
# Self Attention
hidden_states, _ = self.self_attn(
hidden_states=hidden_states,
attention_mask=attention_mask,
position_ids=position_ids,
past_key_values=past_key_values,
cache_position=cache_position,
position_embeddings=position_embeddings,
**kwargs,
)
hidden_states = residual + hidden_states
# Fully Connected
residual = hidden_states
hidden_states = self.post_attention_layernorm(hidden_states)
hidden_states = self.mlp(hidden_states)
# For the MoE layers, we need to unpack
if isinstance(hidden_states, tuple):
hidden_states, _ = hidden_states
hidden_states = residual + hidden_states
return hidden_states
class Qwen3NextPreTrainedModel(PreTrainedModel):
config: Qwen3NextConfig
base_model_prefix = "model"
supports_gradient_checkpointing = True
_no_split_modules = ["Qwen3NextDecoderLayer"]
_skip_keys_device_placement = "past_key_values"
_supports_flash_attn_2 = True
_supports_sdpa = True
_keys_to_ignore_on_load_unexpected = [r"^mtp.*"]
_can_record_outputs = {
"router_logits": OutputRecorder(Qwen3NextSparseMoeBlock, index=1),
"hidden_states": Qwen3NextDecoderLayer,
"attentions": Qwen3NextAttention,
}
_is_stateful = True
def _init_weights(self, module):
super()._init_weights(module)
if isinstance(module, Qwen3NextGatedDeltaNet):
module.dt_bias.data.fill_(1.0)
module.A_log.data.uniform_(0, 16).log_()
class Qwen3NextModel(Qwen3NextPreTrainedModel):
def __init__(self, config: Qwen3NextConfig):
super().__init__(config)
self.embed_tokens = nn.Embedding(config.vocab_size, config.hidden_size, config.pad_token_id)
self.layers = nn.ModuleList(
[Qwen3NextDecoderLayer(config, layer_idx) for layer_idx in range(config.num_hidden_layers)]
)
self.norm = Qwen3NextRMSNorm(config.hidden_size, eps=config.rms_norm_eps)
self.rotary_emb = Qwen3NextRotaryEmbedding(config=config)
self.gradient_checkpointing = False
# Initialize weights and apply final processing
self.post_init()
@check_model_inputs
@auto_docstring
def forward(
self,
input_ids: Optional[torch.LongTensor] = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.LongTensor] = None,
past_key_values: Optional[Cache] = None,
inputs_embeds: Optional[torch.FloatTensor] = None,
use_cache: Optional[bool] = None,
cache_position: Optional[torch.LongTensor] = None,
**kwargs: Unpack[TransformersKwargs],
) -> MoeModelOutputWithPast:
if (input_ids is None) ^ (inputs_embeds is not None):
raise ValueError("You must specify exactly one of input_ids or inputs_embeds")
if inputs_embeds is None:
inputs_embeds = self.embed_tokens(input_ids)
if use_cache and past_key_values is None:
past_key_values = Qwen3NextDynamicCache(config=self.config)
if cache_position is None:
past_seen_tokens = past_key_values.get_seq_length() if past_key_values is not None else 0
cache_position = torch.arange(
past_seen_tokens, past_seen_tokens + inputs_embeds.shape[1], device=inputs_embeds.device
)
if position_ids is None:
position_ids = cache_position.unsqueeze(0)
causal_mask = create_causal_mask(
config=self.config,
input_embeds=inputs_embeds,
attention_mask=attention_mask,
cache_position=cache_position,
past_key_values=past_key_values,
position_ids=position_ids,
)
linear_attn_mask = self._update_linear_attn_mask(attention_mask, cache_position)
hidden_states = inputs_embeds
# create position embeddings to be shared across the decoder layers
position_embeddings = self.rotary_emb(hidden_states, position_ids)
for decoder_layer in self.layers[: self.config.num_hidden_layers]:
layer_mask = linear_attn_mask if decoder_layer.layer_type == "linear_attention" else causal_mask
hidden_states = decoder_layer(
hidden_states,
position_embeddings=position_embeddings,
attention_mask=layer_mask,
position_ids=position_ids,
past_key_values=past_key_values,
use_cache=use_cache,
cache_position=cache_position,
**kwargs,
)
hidden_states = self.norm(hidden_states)
return MoeModelOutputWithPast(
last_hidden_state=hidden_states,
past_key_values=past_key_values,
)
def _update_linear_attn_mask(self, attention_mask, cache_position):
"""
NOTE: Left-padding is used for linear attention mask.
No need for zeroing states when
1. Cached forward
2. Attending to all inputs
"""
linear_attn_mask = attention_mask
if cache_position[0] > 0 or (attention_mask is not None and torch.all(attention_mask == 1)):
linear_attn_mask = None
return linear_attn_mask
def load_balancing_loss_func(
gate_logits: Union[torch.Tensor, tuple[torch.Tensor], None],
num_experts: Optional[int] = None,
top_k=2,
attention_mask: Optional[torch.Tensor] = None,
) -> Union[torch.Tensor, int]:
r"""
Computes auxiliary load balancing loss as in Switch Transformer - implemented in Pytorch.
See Switch Transformer (https://huggingface.co/papers/2101.03961) for more details. This function implements the loss
function presented in equations (4) - (6) of the paper. It aims at penalizing cases where the routing between
experts is too unbalanced.
Args:
gate_logits:
Logits from the `gate`, should be a tuple of model.config.num_hidden_layers tensors of
shape [batch_size X sequence_length, num_experts].
num_experts:
Number of experts
top_k:
The number of experts to route per-token, can be also interpreted as the `top-k` routing
parameter.
attention_mask (`torch.Tensor`, *optional*):
The attention_mask used in forward function
shape [batch_size X sequence_length] if not None.
Returns:
The auxiliary loss.
"""
if gate_logits is None or not isinstance(gate_logits, tuple):
return 0
if isinstance(gate_logits, tuple):
compute_device = gate_logits[0].device
concatenated_gate_logits = torch.cat([layer_gate.to(compute_device) for layer_gate in gate_logits], dim=0)
routing_weights = torch.nn.functional.softmax(concatenated_gate_logits, dim=-1)
_, selected_experts = torch.topk(routing_weights, top_k, dim=-1)
expert_mask = torch.nn.functional.one_hot(selected_experts, num_experts)
if attention_mask is None:
# Compute the percentage of tokens routed to each experts
tokens_per_expert = torch.mean(expert_mask.float(), dim=0)
# Compute the average probability of routing to these experts
router_prob_per_expert = torch.mean(routing_weights, dim=0)
else:
batch_size, sequence_length = attention_mask.shape
num_hidden_layers = concatenated_gate_logits.shape[0] // (batch_size * sequence_length)
# Compute the mask that masks all padding tokens as 0 with the same shape of expert_mask
expert_attention_mask = (
attention_mask[None, :, :, None, None]
.expand((num_hidden_layers, batch_size, sequence_length, top_k, num_experts))
.reshape(-1, top_k, num_experts)
.to(compute_device)
)
# Compute the percentage of tokens routed to each experts
tokens_per_expert = torch.sum(expert_mask.float() * expert_attention_mask, dim=0) / torch.sum(
expert_attention_mask, dim=0
)
# Compute the mask that masks all padding tokens as 0 with the same shape of tokens_per_expert
router_per_expert_attention_mask = (
attention_mask[None, :, :, None]
.expand((num_hidden_layers, batch_size, sequence_length, num_experts))
.reshape(-1, num_experts)
.to(compute_device)
)
# Compute the average probability of routing to these experts
router_prob_per_expert = torch.sum(routing_weights * router_per_expert_attention_mask, dim=0) / torch.sum(
router_per_expert_attention_mask, dim=0
)
overall_loss = torch.sum(tokens_per_expert * router_prob_per_expert.unsqueeze(0))
return overall_loss * num_experts
@auto_docstring
class Qwen3NextForCausalLM(Qwen3NextPreTrainedModel, GenerationMixin):
_tied_weights_keys = ["lm_head.weight"]
_tp_plan = {"lm_head": "colwise_rep"}
_pp_plan = {"lm_head": (["hidden_states"], ["logits"])}
def __init__(self, config):
super().__init__(config)
self.model = Qwen3NextModel(config)
self.vocab_size = config.vocab_size
self.lm_head = nn.Linear(config.hidden_size, config.vocab_size, bias=False)
self.router_aux_loss_coef = config.router_aux_loss_coef
self.num_experts = config.num_experts
self.num_experts_per_tok = config.num_experts_per_tok
# Initialize weights and apply final processing
self.post_init()
@can_return_tuple
@auto_docstring
def forward(
self,
input_ids: Optional[torch.LongTensor] = None,
attention_mask: Optional[torch.Tensor] = None,
position_ids: Optional[torch.LongTensor] = None,
past_key_values: Optional[Qwen3NextDynamicCache] = None,
inputs_embeds: Optional[torch.FloatTensor] = None,
labels: Optional[torch.LongTensor] = None,
use_cache: Optional[bool] = None,
output_router_logits: Optional[bool] = None,
cache_position: Optional[torch.LongTensor] = None,
logits_to_keep: Union[int, torch.Tensor] = 0,
**kwargs: Unpack[TransformersKwargs],
) -> MoeCausalLMOutputWithPast:
r"""
labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
Labels for computing the masked language modeling loss. Indices should either be in `[0, ...,
config.vocab_size]` or -100 (see `input_ids` docstring). Tokens with indices set to `-100` are ignored
(masked), the loss is only computed for the tokens with labels in `[0, ..., config.vocab_size]`.
Example:
```python
>>> from transformers import AutoTokenizer, Qwen3NextForCausalLM
>>> model = Qwen3NextForCausalLM.from_pretrained("Qwen/Qwen3-Next-80B-A3B-Instruct")
>>> tokenizer = AutoTokenizer.from_pretrained("Qwen/Qwen3-Next-80B-A3B-Instruct")
>>> prompt = "Hey, are you conscious? Can you talk to me?"
>>> inputs = tokenizer(prompt, return_tensors="pt")
>>> # Generate
>>> generate_ids = model.generate(inputs.input_ids, max_length=30)
>>> tokenizer.batch_decode(generate_ids, skip_special_tokens=True, clean_up_tokenization_spaces=False)[0]
"Hey, are you conscious? Can you talk to me?\nI'm not conscious, but I can talk to you."
```"""
output_router_logits = (
output_router_logits if output_router_logits is not None else self.config.output_router_logits
)
# decoder outputs consists of (dec_features, layer_state, dec_hidden, dec_attn)
outputs: MoeModelOutputWithPast = self.model(
input_ids=input_ids,
attention_mask=attention_mask,
position_ids=position_ids,
past_key_values=past_key_values,
inputs_embeds=inputs_embeds,
use_cache=use_cache,
output_router_logits=output_router_logits,
cache_position=cache_position,
**kwargs,
)
hidden_states = outputs.last_hidden_state
# Only compute necessary logits, and do not upcast them to float if we are not computing the loss
slice_indices = slice(-logits_to_keep, None) if isinstance(logits_to_keep, int) else logits_to_keep
logits = self.lm_head(hidden_states[:, slice_indices, :])
loss = None
if labels is not None:
loss = self.loss_function(logits, labels, self.vocab_size, **kwargs)
aux_loss = None
if output_router_logits:
aux_loss = load_balancing_loss_func(
outputs.router_logits,
self.num_experts,
self.num_experts_per_tok,
attention_mask,
)
if labels is not None:
loss += self.router_aux_loss_coef * aux_loss.to(loss.device) # make sure to reside in the same device
return MoeCausalLMOutputWithPast(
loss=loss,
aux_loss=aux_loss,
logits=logits,
past_key_values=outputs.past_key_values,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
router_logits=outputs.router_logits,
)
class Qwen3NextForSequenceClassification(GenericForSequenceClassification, Qwen3NextPreTrainedModel):
pass
class Qwen3NextForTokenClassification(GenericForTokenClassification, Qwen3NextPreTrainedModel):
pass
class Qwen3NextForQuestionAnswering(GenericForQuestionAnswering, Qwen3NextPreTrainedModel):
base_model_prefix = "transformer" # For BC, where `transformer` was used instead of `model`
__all__ = [
"Qwen3NextForCausalLM",
"Qwen3NextForQuestionAnswering",
"Qwen3NextModel",
"Qwen3NextPreTrainedModel",
"Qwen3NextForSequenceClassification",
"Qwen3NextForTokenClassification",
]