[Feat] Adapted mtp function to Qwen3-next (#3918)

### What this PR does / why we need it?

Adapts mtp function to Qwen3-next.

- vLLM version: v0.11.0
- vLLM main:
83f478bb19

Signed-off-by: drslark <slarksblood@qq.com>

tests/e2e/multicard/test_qwen3_next.py

@@ -20,10 +20,17 @@
 
 Run `pytest tests/e2e/multicard/test_qwen3_next.py`.
 """
+import os
+from unittest.mock import patch
 
 from tests.e2e.conftest import VllmRunner
 
+# NZ will cause precision error in Qwen3-Next
+# When it is fixed, this set-up can be removed
+_IS_ENABLE_NZ = "VLLM_ASCEND_ENABLE_NZ"
 
+
+@patch.dict(os.environ, {_IS_ENABLE_NZ: "0"})
 def test_models_distributed_Qwen3_NEXT_TP4():
     example_prompts = [
         "Hello, my name is",
@@ -36,8 +43,10 @@ def test_models_distributed_Qwen3_NEXT_TP4():
                     distributed_executor_backend="mp",
                     enforce_eager=True) as vllm_model:
         vllm_model.generate_greedy(example_prompts, max_tokens)
+        del vllm_model
 
 
+@patch.dict(os.environ, {_IS_ENABLE_NZ: "0"})
 def test_models_distributed_Qwen3_NEXT_TP4_FULL_DECODE_ONLY():
     example_prompts = [
         "Hello, my name is",
@@ -54,3 +63,50 @@ def test_models_distributed_Qwen3_NEXT_TP4_FULL_DECODE_ONLY():
                         "cudagraph_capture_sizes": [1, 8, 24, 48, 60]
                     }) as vllm_model:
         vllm_model.generate_greedy(example_prompts, max_tokens)
+        del vllm_model
+
+
+@patch.dict(os.environ, {_IS_ENABLE_NZ: "0"})
+def test_models_distributed_Qwen3_NEXT_MTP_TP4_SIMILARITY():
+    example_prompts = [
+        "Hello, my name is",
+        "The president of the United States is",
+        "The capital of France is",
+        "The future of AI is",
+    ]
+    max_tokens = 20
+
+    with VllmRunner("Qwen/Qwen3-Next-80B-A3B-Instruct",
+                    tensor_parallel_size=4,
+                    max_model_len=4096,
+                    gpu_memory_utilization=0.8,
+                    distributed_executor_backend="mp") as vllm_model:
+        ref_outputs = vllm_model.generate_greedy(example_prompts, max_tokens)
+    del vllm_model
+
+    with VllmRunner("Qwen/Qwen3-Next-80B-A3B-Instruct",
+                    tensor_parallel_size=4,
+                    max_model_len=4096,
+                    gpu_memory_utilization=0.8,
+                    distributed_executor_backend="mp",
+                    speculative_config={
+                        "method": "qwen3_next_mtp",
+                        "num_speculative_tokens": 1
+                    }) as spec_vllm_model:
+        spec_outputs = spec_vllm_model.generate_greedy(example_prompts,
+                                                       max_tokens)
+    del spec_vllm_model
+
+    matches = 0
+    misses = 0
+    for ref_output, spec_output in zip(ref_outputs, spec_outputs):
+        ref_token_ids = ref_output[0]
+        spec_token_ids = spec_output[0]
+        if ref_token_ids == spec_token_ids[:len(ref_token_ids)]:
+            matches += 1
+        else:
+            misses += 1
+            print(f"ref_output: {ref_output[1]}")
+            print(f"spec_output: {spec_output[1]}")
+
+    assert matches > int(0.66 * len(ref_outputs))

tests/ut/attention/test_attention_v1.py

@@ -77,6 +77,7 @@ class TestAscendAttentionMetadataBuilder(TestBase):
         mock_get_dcp_group.return_value = dcp_group
 
         self.mock_vllm_config = MagicMock()
+        self.mock_vllm_config.speculative_config = None
         self.mock_vllm_config.model_config.max_model_len = 640
         self.mock_vllm_config.cache_config.block_size = 64
         self.mock_vllm_config.compilation_config.cudagraph_mode = None

vllm_ascend/attention/attention_v1.py

@@ -252,6 +252,17 @@ class AscendAttentionMetadataBuilder:
         self.dcp_rank = get_decode_context_model_parallel_rank(
         ) if self.dcp_size > 1 else 0
 
+        self.speculative_config = vllm_config.speculative_config
+        self.decode_threshold = 1
+        if self.speculative_config:
+            spec_token_num = self.speculative_config.num_speculative_tokens
+            self.decode_threshold += spec_token_num
+            assert self.decode_threshold <= 16, f"decode_threshold exceeded \
+                npu_fused_infer_attention_score TND layout's limit of 16, \
+                got {self.decode_threshold}"
+
+        AscendAttentionMetadataBuilder.reorder_batch_threshold = self.decode_threshold
+
     def reorder_batch(self, input_batch,
                       scheduler_output: "SchedulerOutput") -> bool:
         return False

vllm_ascend/models/__init__.py

@@ -35,6 +35,10 @@ def register_model():
         "PanguProMoEForCausalLM",
         "vllm_ascend.torchair.models.torchair_pangu_moe:PanguProMoEForCausalLM"
     )
+
     ModelRegistry.register_model(
         "Qwen3NextForCausalLM",
         "vllm_ascend.models.qwen3_next:CustomQwen3NextForCausalLM")
+
+    ModelRegistry.register_model(
+        "Qwen3NextMTP", "vllm_ascend.models.qwen3_next_mtp:CustomQwen3NextMTP")

vllm_ascend/models/qwen3_next.py

@@ -260,6 +260,24 @@ class CustomQwen3NextGatedDeltaNet(Qwen3NextGatedDeltaNet, MambaBase):
             mixed_qkv_spec = None
             mixed_qkv_non_spec = mixed_qkv
 
+        # 2.1: process the mutli-query part
+        if spec_sequence_masks is not None:
+            mixed_qkv_spec = mixed_qkv_spec.view(
+                attn_metadata.num_spec_decodes, -1, mixed_qkv_spec.size(-1))
+            mixed_qkv_spec = rearrange(mixed_qkv_spec, 'b l d -> b d l')
+            mixed_qkv_spec = causal_conv1d_update(
+                mixed_qkv_spec,
+                conv_state,
+                conv_weights,
+                self.conv1d.bias,
+                self.activation,
+                conv_state_indices=spec_state_indices_tensor[:, 0]
+                [:attn_metadata.num_spec_decodes],
+                num_accepted_tokens=num_accepted_tokens,
+                validate_data=False,
+            )
+            mixed_qkv_spec = rearrange(mixed_qkv_spec, 'b d l -> (b l) d')
+
         # 2.2: process the remaining part
         if attn_metadata.num_prefills > 0:
             # - "cache_indices" updates the conv_state cache in positions

vllm_ascend/models/qwen3_next_mtp.py

@@ -0,0 +1,109 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+"""Inference-only Qwen3Next MTP model."""
+import torch
+from vllm.compilation.decorators import support_torch_compile
+from vllm.config import VllmConfig
+from vllm.model_executor.layers.linear import ColumnParallelLinear
+from vllm.model_executor.layers.logits_processor import LogitsProcessor
+from vllm.model_executor.layers.vocab_parallel_embedding import (
+    DEFAULT_VOCAB_PADDING_SIZE, ParallelLMHead, VocabParallelEmbedding)
+from vllm.model_executor.models.interfaces import SupportsPP
+from vllm.model_executor.models.qwen3_next_mtp import (
+    Qwen3NextMTP, Qwen3NextMultiTokenPredictor)
+from vllm.model_executor.models.utils import (
+    make_empty_intermediate_tensors_factory, maybe_prefix)
+from vllm.transformers_utils.configs import Qwen3NextConfig
+
+from vllm_ascend.models.qwen3_next import (CustomQwen3NextDecoderLayer,
+                                           Qwen3NextRMSNorm)
+
+
+@support_torch_compile
+class CustomQwen3NextMultiTokenPredictor(Qwen3NextMultiTokenPredictor):
+
+    def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""):
+        super(Qwen3NextMultiTokenPredictor, self).__init__()
+
+        model_config = vllm_config.model_config
+        quant_config = vllm_config.quant_config
+        lora_config = vllm_config.lora_config
+        config: Qwen3NextConfig = model_config.hf_config
+
+        self.config = config
+        lora_vocab = ((lora_config.lora_extra_vocab_size *
+                       (lora_config.max_loras or 1)) if lora_config else 0)
+        self.vocab_size = config.vocab_size + lora_vocab
+        self.org_vocab_size = config.vocab_size
+
+        self.mtp_start_layer_idx = config.num_hidden_layers
+        self.num_mtp_layers = getattr(config, "num_nextn_predict_layers", 1)
+
+        self.embed_tokens = VocabParallelEmbedding(
+            self.vocab_size,
+            config.hidden_size,
+            org_num_embeddings=config.vocab_size,
+        )
+
+        self.fc = ColumnParallelLinear(self.config.hidden_size * 2,
+                                       self.config.hidden_size,
+                                       gather_output=True,
+                                       bias=False,
+                                       return_bias=False,
+                                       quant_config=quant_config,
+                                       prefix=f'{prefix}.fc')
+
+        # use old version mtp layer name to avoid a exception in vllm
+        self.layers = torch.nn.ModuleList(
+            CustomQwen3NextDecoderLayer(
+                vllm_config,
+                layer_type="full_attention",
+                prefix=f'{prefix}.layers.{self.mtp_start_layer_idx + idx}',
+            ) for idx in range(self.num_mtp_layers))
+
+        self.make_empty_intermediate_tensors = (
+            make_empty_intermediate_tensors_factory(
+                ["hidden_states", "residual"], config.hidden_size))
+
+        self.norm = Qwen3NextRMSNorm(config.hidden_size,
+                                     eps=config.rms_norm_eps)
+        self.pre_fc_norm_hidden = Qwen3NextRMSNorm(config.hidden_size,
+                                                   eps=config.rms_norm_eps)
+        self.pre_fc_norm_embedding = Qwen3NextRMSNorm(config.hidden_size,
+                                                      eps=config.rms_norm_eps)
+
+
+@support_torch_compile
+class CustomQwen3NextMTP(Qwen3NextMTP, SupportsPP):
+    packed_modules_mapping = {
+        "qkv_proj": [
+            "q_proj",
+            "k_proj",
+            "v_proj",
+        ],
+        "gate_up_proj": ["up_proj", "down_proj"]
+    }
+
+    def __init__(self, *, vllm_config: VllmConfig, prefix: str = ""):
+        config = vllm_config.model_config.hf_config
+        self.vllm_config = vllm_config
+        cache_config = vllm_config.cache_config
+        assert not cache_config.enable_prefix_caching, \
+            "Qwen3NextMTP currently does not support prefix caching"
+
+        self.quant_config = vllm_config.quant_config
+
+        super(Qwen3NextMTP, self).__init__()
+        self.config = config
+        self.model = CustomQwen3NextMultiTokenPredictor(
+            vllm_config=vllm_config, prefix=maybe_prefix(prefix, "model"))
+        self.unpadded_vocab_size = config.vocab_size
+        self.lm_head = ParallelLMHead(self.unpadded_vocab_size,
+                                      config.hidden_size,
+                                      org_num_embeddings=config.vocab_size,
+                                      padding_size=DEFAULT_VOCAB_PADDING_SIZE,
+                                      prefix=maybe_prefix(prefix, "lm_head"))
+        self.logits_processor = LogitsProcessor(self.unpadded_vocab_size,
+                                                config.vocab_size)
+        self.make_empty_intermediate_tensors = (
+            self.model.make_empty_intermediate_tensors)

vllm_ascend/ops/casual_conv1d.py

@@ -55,7 +55,7 @@ def causal_conv1d_ref(
         final_states = F.pad(x, (width - 1 - x.shape[-1], 0)).to(
             dtype_in)  # (batch, dim, width - 1)
         if final_states_out is not None:
-            final_states_out.copy_(final_states)
+            final_states_out[..., :(width - 1)].copy_(final_states)
         else:
             final_states_out = final_states
     out = (out if activation is None else F.silu(out)).to(dtype=dtype_in)

vllm_ascend/spec_decode/__init__.py

@@ -29,9 +29,9 @@ def get_spec_decode_method(method,
                            is_torchair_graph=False):
     if method == "ngram":
         return NgramProposer(vllm_config, device, runner)
-    elif method in ["eagle", "eagle3"]:
+    elif method in ("eagle", "eagle3"):
         return EagleProposer(vllm_config, device, runner)
-    elif method == 'deepseek_mtp':
+    elif method in ('deepseek_mtp', 'qwen3_next_mtp'):
         if is_torchair_graph:
             return TorchairMtpProposer(vllm_config, device, runner)
         return MtpProposer(vllm_config, device, runner)

vllm_ascend/spec_decode/mtp_proposer.py

@@ -1,3 +1,4 @@
+import importlib
 from typing import Optional
 
 import numpy as np
@@ -12,7 +13,6 @@ from vllm.model_executor.layers.attention_layer_base import AttentionLayerBase
 from vllm.model_executor.model_loader import get_model_loader
 from vllm.model_executor.model_loader.utils import \
     process_weights_after_loading
-from vllm.model_executor.models.deepseek_mtp import DeepSeekMTP
 from vllm.model_executor.models.deepseek_v2 import DeepseekV32IndexerCache
 from vllm.model_executor.models.llama_eagle3 import Eagle3LlamaForCausalLM
 from vllm.utils import cdiv
@@ -42,6 +42,26 @@ logger = init_logger(__name__)
 
 PADDING_SLOT_ID = -1
 
+_MTP_MODELS = {
+    "DeepseekV3ForCausalLM":
+    ("vllm.model_executor.models.deepseek_mtp", "DeepSeekMTP"),
+    "Qwen3NextForCausalLM":
+    ("vllm_ascend.models.qwen3_next_mtp", "CustomQwen3NextMTP")
+}
+
+_DEFAULT_FIRST_LAYER = 'model.layers.0.self_attn.attn'
+
+_FIRST_LAYERS = {"Qwen3NextForCausalLM": 'model.layers.3.self_attn.attn'}
+
+
+def _load_model(architecture):
+    if architecture not in _MTP_MODELS:
+        raise ValueError("Invalid architecture for mtp.")
+    module_name, model_name = _MTP_MODELS[architecture]
+    module = importlib.import_module(module_name)
+    model = getattr(module, model_name)
+    return model
+
 
 class MtpProposer(Proposer):
 
@@ -150,9 +170,7 @@ class MtpProposer(Proposer):
         with set_default_torch_dtype(
                 draft_model_config.dtype), set_current_vllm_config(
                     self.vllm_config):
-            self.model = DeepSeekMTP(
+            self._init_mtp_model()
-                vllm_config=self.vllm_config).to(target_device)
-
         draft_attn_layer_names = (get_layers_from_vllm_config(
             self.vllm_config, AttentionLayerBase).keys() -
                                   target_attn_layer_names)
@@ -228,8 +246,7 @@ class MtpProposer(Proposer):
                            attn_metadata=None,
                            aux_hidden_states: torch.Tensor = None):
         common_attn_metadata = self.runner.spec_decode_common_attn_metadata
-        if attn_metadata is not None and isinstance(attn_metadata, dict):
+        attn_metadata = self._get_attn_metadata(attn_metadata)
-            attn_metadata = attn_metadata['model.layers.0.self_attn.attn']
 
         if self.speculative_config.disable_padded_drafter_batch:
             # When padded-batch is disabled, the sampled_token_ids should be
@@ -311,6 +328,20 @@ class MtpProposer(Proposer):
 
         return draft_token_ids
 
+    def _init_mtp_model(self):
+        architecture = self.vllm_config.model_config.architecture
+        target_device = self.vllm_config.device_config.device
+        model = _load_model(architecture)
+        self.model = model(vllm_config=self.vllm_config).to(target_device)
+
+    def _get_attn_metadata(self, attn_metadata):
+        if attn_metadata is not None and isinstance(attn_metadata, dict):
+            architecture = self.vllm_config.model_config.architecture
+            layer_name = _FIRST_LAYERS.get(architecture, _DEFAULT_FIRST_LAYER)
+            attn_metadata = attn_metadata[layer_name]
+
+        return attn_metadata
+
     def _prepare_inputs(
         self,
         common_attn_metadata: CommonAttentionMetadata,

vllm_ascend/worker/model_runner_v1.py

@@ -1852,7 +1852,7 @@ class NPUModelRunner(LoRAModelRunnerMixin):
                         extra_attn_metadata_args = dict(
                             num_accepted_tokens=self.num_accepted_tokens.
                             gpu[:num_reqs],
-                            num_draft_tokens=self.num_draft_tokens.
+                            num_decode_draft_tokens_cpu=self.num_draft_tokens.
                             gpu[:num_reqs],
                         )
                     attn_metadata_i = builder.build(
@@ -1948,11 +1948,10 @@ class NPUModelRunner(LoRAModelRunnerMixin):
                 attn_state = AscendAttentionState.SpecDecoding
         # Speculative decoding.
         elif np.all(num_valid_tokens == 1):
-            if self.drafter and (self.drafter.name == SpecDcodeType.EAGLE
+            if self.speculative_config and self.speculative_config.method == 'deepseek_mtp':
-                                 or self.drafter.name == SpecDcodeType.EAGLE3):
-                attn_state = AscendAttentionState.ChunkedPrefill
-            else:
                 attn_state = AscendAttentionState.SpecDecoding
+            else:
+                attn_state = AscendAttentionState.ChunkedPrefill
         # splitfuse
         elif not ascend_config.ascend_scheduler_config.enabled or self.chunked_prefill_enabled:
             attn_state = AscendAttentionState.ChunkedPrefill
@@ -2548,7 +2547,7 @@ class NPUModelRunner(LoRAModelRunnerMixin):
         with ProfileExecuteDuration().capture_async("Draft"):
             if self.speculative_config:
                 use_padded_batch_for_eagle = self.speculative_config and \
-                    self.speculative_config.method == "deepseek_mtp" and \
+                    self.speculative_config.method in ("deepseek_mtp", "qwen3_next_mtp") and \
                     not self.speculative_config.disable_padded_drafter_batch
                 if use_padded_batch_for_eagle:
                     # EAGLE speculative decoding can use the GPU sampled tokens