[NPU][Diffusion] Optimize SenseNova-U1 batched generation (#39382)

Signed-off-by: syd520zy <529477025@qq.com>
Co-authored-by: ronnie_zheng <zl19940307@163.com>

docs/cookbook/diffusion/SenseNova/SenseNova-U1.5-8B-MoT.mdx

@@ -78,11 +78,38 @@ with open("output_sensenova_u15.png", "wb") as f:
     f.write(image_bytes)
 ```
 
-## 5. Benchmark
+## 5. Advanced usage
 
-### 5.1 Speedup Benchmark
+### 5.1 Dynamic request batching
 
-#### 5.1.1 Single-run Profile
+Start the server with dynamic batching enabled:
+
+```bash Command
+sglang serve \
+  --model-path sensenova/SenseNova-U1.5-8B-MoT \
+  --port 30000 \
+  --batching-max-size 2 \
+  --batching-delay-ms 100
+```
+
+Submit requests concurrently so they arrive within the batching delay. Requests
+in one batch must use the same resolution, inference steps, guidance settings,
+and output options. Requests with multiple outputs or `think_mode=true` are
+executed sequentially.
+
+### 5.2 Ascend NPU optimizations
+
+On Ascend NPU, SenseNova-U1 automatically uses fused inference attention,
+RMSNorm, and SwiGLU MLP operators for supported inputs. FIA and SwiGLU fall back
+when their requirements are not met. Run one complete warmup request before
+benchmarking because the fused MLP packs its gate and up projection weights on
+first use.
+
+## 6. Benchmark
+
+### 6.1 Speedup benchmark
+
+#### 6.1.1 Single-run profile
 
 <Tabs>
   <Tab title="NVIDIA A800">
@@ -137,4 +164,21 @@ with open("output_sensenova_u15.png", "wb") as f:
     ------------------------------------------------------------
     ```
   </Tab>
+  <Tab title="Ascend 910C">
+
+    Environment: one Ascend 910C; workload: four concurrent 2048 x 2048
+    text-to-image requests, 50 denoising steps, CFG 4, BF16.
+
+    | Batch size | NPU operators | Duration (s) | Throughput (images/s) | Mean latency (s) | Peak reserved memory (MB) |
+    |---:|---|---:|---:|---:|---:|
+    | 1 | Disabled | 234.28 | 0.01707 | 146.47 | 35698 |
+    | 2 | Disabled | 234.83 | 0.01703 | 176.06 | 37870 |
+    | 1 | FIA + RMSNorm + SwiGLU | 205.94 | 0.01942 | 128.80 | 35718 |
+    | 2 | FIA + RMSNorm + SwiGLU | 195.02 | 0.02051 | 146.33 | 37850 |
+
+    Optimized B1 improves throughput by 13.76% over unoptimized B1. Optimized
+    B2 improves throughput by 20.42% over unoptimized B2 and by 5.60% over
+    optimized B1.
+
+  </Tab>
 </Tabs>

python/sglang/multimodal_gen/configs/pipeline_configs/base.py

@@ -426,6 +426,10 @@ class PipelineConfig:
         """
         return self.task_type in (ModelTaskType.T2I, ModelTaskType.T2V)
 
+    def supports_dynamic_batching_for_request(self, batch) -> bool:
+        """Return whether one request may participate in dynamic batching."""
+        return True
+
     def supports_disaggregation(self) -> bool:
         """Return whether multi-service disaggregated deployment is supported."""
 

python/sglang/multimodal_gen/configs/pipeline_configs/sensenova_u1.py

@@ -8,6 +8,10 @@ from sglang.multimodal_gen.configs.pipeline_configs.base import (
 from sglang.multimodal_gen.configs.pipeline_configs.model_deployment_config import (
     ModelDeploymentConfig,
 )
+from sglang.multimodal_gen.configs.sensenova_u1 import (
+    DEFAULT_THINK_MODE,
+    RESOLUTION_ALIGNMENT,
+)
 
 
 def _is_runtime_option_requested(value) -> bool:
@@ -81,7 +85,23 @@ class SenseNovaU1PipelineConfig(PipelineConfig):
     supports_cfg_parallel: bool = False
 
     def supports_dynamic_batching(self):
-        return False
+        return True
+
+    def supports_dynamic_batching_for_request(self, batch) -> bool:
+        sampling_params = getattr(batch, "sampling_params", None)
+        return not bool(getattr(sampling_params, "think_mode", DEFAULT_THINK_MODE))
+
+    def estimate_request_cost(self, batch) -> float:
+        image_tokens = (int(batch.width) // RESOLUTION_ALIGNMENT) * (
+            int(batch.height) // RESOLUTION_ALIGNMENT
+        )
+        cfg_branches = 2 if float(batch.guidance_scale) > 1 else 1
+        return float(
+            image_tokens
+            * int(batch.num_inference_steps)
+            * cfg_branches
+            * int(batch.num_outputs_per_prompt)
+        )
 
     def supports_disaggregation(self) -> bool:
         return False

python/sglang/multimodal_gen/configs/sample/sensenova_u1.py

@@ -13,9 +13,9 @@ from sglang.multimodal_gen.configs.sensenova_u1 import (
     DEFAULT_T_EPS,
     DEFAULT_THINK_MODE,
     DEFAULT_TIMESTEP_SHIFT,
+    RESOLUTION_ALIGNMENT,
     SENSENOVA_U1_CFG_NORM_CHOICES,
     SENSENOVA_U1_REQUEST_EXTRA_KEY,
-    SENSENOVA_U1_RESOLUTION_ALIGNMENT,
 )
 
 _PUBLIC_OVERRIDE_FIELDS = {
@@ -74,12 +74,12 @@ class SenseNovaU1SamplingParams(SamplingParams):
     def _validate(self) -> None:
         super()._validate()
         if (
-            self.width % SENSENOVA_U1_RESOLUTION_ALIGNMENT != 0
+            self.width % RESOLUTION_ALIGNMENT != 0
-            or self.height % SENSENOVA_U1_RESOLUTION_ALIGNMENT != 0
+            or self.height % RESOLUTION_ALIGNMENT != 0
         ):
             raise ValueError(
                 "SenseNova-U1 requires width and height to be divisible by "
-                f"{SENSENOVA_U1_RESOLUTION_ALIGNMENT}, got "
+                f"{RESOLUTION_ALIGNMENT}, got "
                 f"{self.width}x{self.height}."
             )
         if self.num_frames != 1:

python/sglang/multimodal_gen/configs/sensenova_u1.py

@@ -19,7 +19,7 @@ SENSENOVA_U1_CFG_NORM_CHOICES = (
     "channel",
     "cfg_zero_star",
 )
-SENSENOVA_U1_RESOLUTION_ALIGNMENT = 32
+RESOLUTION_ALIGNMENT = 32
 
 DEFAULT_CFG_NORM = "none"
 DEFAULT_TIMESTEP_SHIFT = 3.0

python/sglang/multimodal_gen/runtime/managers/scheduler.py

@@ -44,6 +44,9 @@ from sglang.multimodal_gen.runtime.managers.dynamic_batch_admission import (
 )
 from sglang.multimodal_gen.runtime.managers.gpu_worker import GPUWorker
 from sglang.multimodal_gen.runtime.pipelines_core import Req
+from sglang.multimodal_gen.runtime.pipelines_core.request_utils import (
+    normalize_output_seeds,
+)
 from sglang.multimodal_gen.runtime.pipelines_core.schedule_batch import (
     BatchMetricsWindow,
     OutputBatch,
@@ -559,6 +562,12 @@ class Scheduler(SchedulerWarmupMixin, SchedulerPostTrainingMixin, SchedulerDisag
 
         if base_req.is_warmup or candidate_req.is_warmup:
             return "warmup"
+        if self._requires_sequential_multi_output(base_req, candidate_req):
+            return "sequential_multi_output"
+        if not self._pipeline_supports_dynamic_batching_for_request(
+            base_req, candidate_req
+        ):
+            return "pipeline_request_unsupported"
         if self._has_realtime_session(base_req) or self._has_realtime_session(
             candidate_req
         ):
@@ -589,11 +598,35 @@ class Scheduler(SchedulerWarmupMixin, SchedulerPostTrainingMixin, SchedulerDisag
     def _has_realtime_session(req: Req) -> bool:
         return bool(req.realtime_session_id) or req.session is not None
 
+    def _requires_sequential_multi_output(self, *reqs: Req) -> bool:
+        pipeline_config = self.server_args.pipeline_config
+        return (
+            pipeline_config.supports_sequential_multi_output_inference()
+            and not pipeline_config.supports_sequential_dit_inference()
+            and any(max(1, int(req.num_outputs_per_prompt or 1)) > 1 for req in reqs)
+        )
+
+    def _pipeline_supports_dynamic_batching_for_request(self, *reqs: Req) -> bool:
+        checker = getattr(
+            self.server_args.pipeline_config,
+            "supports_dynamic_batching_for_request",
+            None,
+        )
+        return not callable(checker) or all(checker(req) for req in reqs)
+
     def _can_dynamic_batch(self, base_req: Req, candidate_req: Req) -> bool:
         """Return whether `candidate_req` can be merged into a batch with `base_req`."""
         if base_req.is_warmup or candidate_req.is_warmup:
             return False
 
+        if self._requires_sequential_multi_output(base_req, candidate_req):
+            return False
+
+        if not self._pipeline_supports_dynamic_batching_for_request(
+            base_req, candidate_req
+        ):
+            return False
+
         if self._has_realtime_session(base_req) or self._has_realtime_session(
             candidate_req
         ):
@@ -842,11 +875,26 @@ class Scheduler(SchedulerWarmupMixin, SchedulerPostTrainingMixin, SchedulerDisag
             if not self._can_dynamic_batch(base_req, req):
                 return None
 
+        dynamic_batch_seeds: list[int | list[int]] = []
+        try:
+            for req in reqs:
+                if max(1, int(req.num_outputs_per_prompt or 1)) == 1:
+                    dynamic_batch_seeds.append(
+                        normalize_output_seeds(
+                            req.seed,
+                            num_outputs_per_prompt=1,
+                        )[0]
+                    )
+                else:
+                    dynamic_batch_seeds.append(req.seed)
+        except (TypeError, ValueError):
+            return None
+
         merged_req = deepcopy(base_req)
         merged_req.prompt = [req.prompt for req in reqs]
 
         merged_req.extra = deepcopy(merged_req.extra)
-        merged_req.extra["dynamic_batch_seeds"] = [req.seed for req in reqs]
+        merged_req.extra["dynamic_batch_seeds"] = dynamic_batch_seeds
         merged_req.return_file_paths_only = base_req.return_file_paths_only
         if merged_req.return_file_paths_only:
             dynamic_output_paths: list[str] = []

python/sglang/multimodal_gen/runtime/models/sensenova_u1/neo_unify/modeling_neo_chat.py

@@ -21,7 +21,11 @@ from .modeling_fm_modules import (
     TimestepEmbedder,
 )
 from .modeling_neo_vit import NEOVisionModel
-from .modeling_qwen3 import Qwen3ForCausalLM, create_block_causal_mask
+from .modeling_qwen3 import (
+    Qwen3ForCausalLM,
+    create_block_causal_mask,
+    npu_fia_available,
+)
 from .modeling_qwen3_moe import Qwen3MoeForCausalLM
 from .utils import SYSTEM_MESSAGE_FOR_GEN, load_image_native
 
@@ -37,20 +41,39 @@ def version_cmp(v1, v2, op="eq"):
     return op_func(version.parse(v1), version.parse(v2))
 
 
+def _copy_right_aligned_prefix_bnsd(destination, source, lengths):
+    prefix_width = source.shape[2]
+    for batch_index, length in enumerate(lengths):
+        destination[batch_index, :, prefix_width - length : prefix_width].copy_(
+            source[batch_index, :, :length]
+        )
+
+
 def prepare_flash_kv_cache(
     past_key_values,
     current_len: int,
     batch_size: int,
+    prefix_lengths: Optional[torch.Tensor] = None,
 ):
     """
-    Convert prefix cache from [B, H, S, D] to flash-attn friendly [B, S, H, D],
+    Preallocate the full KV buffer for [prefix + current]. CUDA/SDPA use
-    and preallocate full KV buffer for [prefix + current].
+    [B, S, H, D], while NPU FIA keeps the source [B, H, S, D] layout.
 
     This is done once before denoising loop.
     """
     if past_key_values is None:
         return
 
+    lengths = None
+    if prefix_lengths is not None:
+        lengths = [int(length) for length in prefix_lengths.reshape(-1).tolist()]
+        if len(lengths) == 1 and batch_size > 1:
+            lengths *= batch_size
+        if len(lengths) != batch_size:
+            raise ValueError(
+                f"Expected {batch_size} prefix lengths, got {len(lengths)}"
+            )
+
     for layer in past_key_values.layers:
         past_k = layer.keys
         past_v = layer.values
@@ -60,15 +83,47 @@ def prepare_flash_kv_cache(
             layer.flash_total_len = current_len
             layer.flash_k_cache = None
             layer.flash_v_cache = None
+            layer.flash_actual_seq_lengths_kv = None
+            layer.flash_kv_padding_size = None
+            layer.flash_cache_layout = None
             continue
 
-        # original cache layout assumed: [B, H, S, D]
+        # original cache layout: [B, H, S, D]
-        past_k_flash = past_k.transpose(1, 2).contiguous()  # [B, S, H, D]
+        prefix_len = past_k.shape[2]
-        past_v_flash = past_v.transpose(1, 2).contiguous()  # [B, S, H, D]
-
-        prefix_len = past_k_flash.shape[1]
         total_len = prefix_len + current_len
+        if lengths is not None and any(
+            length < 0 or length > prefix_len for length in lengths
+        ):
+            raise ValueError(
+                f"Prefix lengths must be between 0 and {prefix_len}, got {lengths}"
+            )
 
+        use_npu_fia = (
+            past_k.device.type == "npu" and lengths is not None and npu_fia_available()
+        )
+        if use_npu_fia:
+            k_cache = torch.empty(
+                (batch_size, past_k.shape[1], total_len, past_k.shape[3]),
+                device=past_k.device,
+                dtype=past_k.dtype,
+            )
+            v_cache = torch.empty(
+                (batch_size, past_v.shape[1], total_len, past_v.shape[3]),
+                device=past_v.device,
+                dtype=past_v.dtype,
+            )
+            _copy_right_aligned_prefix_bnsd(k_cache, past_k, lengths)
+            _copy_right_aligned_prefix_bnsd(v_cache, past_v, lengths)
+            layer.flash_actual_seq_lengths_kv = [
+                length + current_len for length in lengths
+            ]
+            layer.flash_kv_padding_size = torch.zeros(
+                1, dtype=torch.int64, device=past_k.device
+            )
+            layer.flash_cache_layout = "BNSD"
+        else:
+            past_k_flash = past_k.transpose(1, 2).contiguous()
+            past_v_flash = past_v.transpose(1, 2).contiguous()
             k_cache = torch.empty(
                 (batch_size, total_len, past_k_flash.shape[2], past_k_flash.shape[3]),
                 device=past_k_flash.device,
@@ -79,9 +134,15 @@ def prepare_flash_kv_cache(
                 device=past_v_flash.device,
                 dtype=past_v_flash.dtype,
             )
-
             k_cache[:, :prefix_len].copy_(past_k_flash)
             v_cache[:, :prefix_len].copy_(past_v_flash)
+            layer.flash_actual_seq_lengths_kv = (
+                None
+                if lengths is None or past_k.device.type == "npu"
+                else [length + current_len for length in lengths]
+            )
+            layer.flash_kv_padding_size = None
+            layer.flash_cache_layout = "BSND"
 
         layer.flash_prefix_len = prefix_len
         layer.flash_total_len = total_len
@@ -101,6 +162,12 @@ def clear_flash_kv_cache(past_key_values):
             delattr(layer, "flash_k_cache")
         if hasattr(layer, "flash_v_cache"):
             delattr(layer, "flash_v_cache")
+        if hasattr(layer, "flash_actual_seq_lengths_kv"):
+            delattr(layer, "flash_actual_seq_lengths_kv")
+        if hasattr(layer, "flash_kv_padding_size"):
+            delattr(layer, "flash_kv_padding_size")
+        if hasattr(layer, "flash_cache_layout"):
+            delattr(layer, "flash_cache_layout")
 
 
 def optimized_scale(positive_flat, negative_flat):
@@ -127,7 +194,21 @@ def optimized_scale(positive_flat, negative_flat):
     return st_star
 
 
-def _randn_with_seed(shape, *, device, dtype, seed: int) -> torch.Tensor:
+def _randn_with_seed(shape, *, device, dtype, seed: int | list[int]) -> torch.Tensor:
+    if isinstance(seed, list):
+        if len(shape) == 0 or len(seed) != shape[0]:
+            raise ValueError(
+                f"expected one seed per batch item, got {len(seed)} seeds for shape {shape}"
+            )
+        return torch.cat(
+            [
+                _randn_with_seed(
+                    (1, *shape[1:]), device=device, dtype=dtype, seed=item_seed
+                )
+                for item_seed in seed
+            ],
+            dim=0,
+        )
     try:
         generator = torch.Generator(device)
     except (RuntimeError, TypeError):
@@ -554,21 +635,61 @@ class NEOChatModel(PreTrainedModel):
             return template.get_prompt() + append_text
         return template.get_prompt()
 
-    def _build_t2i_text_inputs(self, tokenizer, query: str):
+    def _build_t2i_text_inputs(self, tokenizer, query: str | list[str]):
-        model_inputs = tokenizer(query, return_tensors="pt")
+        queries = [query] if isinstance(query, str) else query
-        input_ids = model_inputs["input_ids"].to(self.device)
+        if not queries:
+            raise ValueError("query batch must not be empty")
+        encoded = [
+            tokenizer(item, return_tensors="pt")["input_ids"][0] for item in queries
+        ]
+        lengths = [item.shape[0] for item in encoded]
+        prefix_lengths = torch.tensor(lengths, dtype=torch.long, device=self.device)
+        max_length = max(lengths)
+        pad_token_id = getattr(tokenizer, "pad_token_id", None)
+        if pad_token_id is None:
+            pad_token_id = getattr(tokenizer, "eos_token_id", None)
+        if pad_token_id is None:
+            pad_token_id = 0
+
+        input_ids = torch.full(
+            (len(encoded), max_length),
+            int(pad_token_id),
+            dtype=encoded[0].dtype,
+            device=self.device,
+        )
+        key_valid_mask = torch.zeros(
+            (len(encoded), max_length), dtype=torch.bool, device=self.device
+        )
+        for batch_index, item in enumerate(encoded):
+            item = item.to(self.device)
+            item_length = item.shape[0]
+            input_ids[batch_index, :item_length] = item
+            key_valid_mask[batch_index, :item_length] = True
 
         t_idx = torch.arange(
-            0, input_ids.shape[1], dtype=torch.long, device=input_ids.device
+            max_length, dtype=torch.long, device=input_ids.device
-        )
+        ).expand(len(encoded), -1)
         h_idx = torch.zeros_like(t_idx)
         w_idx = torch.zeros_like(t_idx)
-        indexes = torch.stack([t_idx, h_idx, w_idx], dim=0)
+        batched_indexes = torch.stack([t_idx, h_idx, w_idx], dim=1)
+        indexes = batched_indexes[0] if len(encoded) == 1 else batched_indexes
 
-        attention_mask = {"full_attention": create_block_causal_mask(indexes[0])}
+        attention_mask = {
-        return input_ids, indexes, attention_mask
+            "full_attention": create_block_causal_mask(t_idx, key_valid_mask)
+        }
+        return input_ids, indexes, attention_mask, key_valid_mask, prefix_lengths
 
     def _build_t2i_image_indexes(self, token_h, token_w, text_len, device):
+        if isinstance(text_len, torch.Tensor):
+            text_len = text_len.to(device=device, dtype=torch.long).reshape(-1)
+            batch_size = text_len.shape[0]
+            image_len = token_h * token_w
+            t_image = text_len[:, None].expand(batch_size, image_len)
+            idx = torch.arange(image_len, device=device, dtype=torch.long)
+            h_image = (idx // token_w).expand(batch_size, -1)
+            w_image = (idx % token_w).expand(batch_size, -1)
+            return torch.stack([t_image, h_image, w_image], dim=1)
+
         t_image = torch.full(
             (token_h * token_w,), text_len, dtype=torch.long, device=device
         )
@@ -2140,6 +2261,16 @@ class NEOChatModel(PreTrainedModel):
             timesteps = self._apply_time_schedule(
                 timesteps, token_h * token_w, timestep_shift
             )
+        denoise_embeddings = None
+        if device.type == "npu":
+            denoise_embeddings = self.fm_modules["timestep_embedder"](timesteps[:-1])
+            if self.add_noise_scale_embedding:
+                noise_level = timesteps.new_tensor(
+                    [noise_scale / self.noise_scale_max_value]
+                )
+                denoise_embeddings = denoise_embeddings + self.fm_modules[
+                    "noise_scale_embedder"
+                ](noise_level)
 
         for step_i in range(num_steps):
             t = timesteps[step_i]
@@ -2157,18 +2288,20 @@ class NEOChatModel(PreTrainedModel):
                 gen_model=True,
                 grid_hw=grid_hw,
             ).view(batch_size, token_h * token_w, -1)
+            if denoise_embeddings is not None:
+                timestep_embeddings = denoise_embeddings[step_i].view(1, 1, -1)
+            else:
                 t_expanded = t.expand(batch_size * token_h * token_w)
-            timestep_embeddings = self.fm_modules["timestep_embedder"](t_expanded).view(
+                timestep_embeddings = self.fm_modules["timestep_embedder"](
-                batch_size, token_h * token_w, -1
+                    t_expanded
-            )
+                ).view(batch_size, token_h * token_w, -1)
                 if self.add_noise_scale_embedding:
                     noise_scale_tensor = torch.full_like(
                         t_expanded, noise_scale / self.noise_scale_max_value
                     )
-                noise_embeddings = self.fm_modules["noise_scale_embedder"](
+                    timestep_embeddings += self.fm_modules["noise_scale_embedder"](
                         noise_scale_tensor
                     ).view(batch_size, token_h * token_w, -1)
-                timestep_embeddings += noise_embeddings
             image_embeds = image_embeds + timestep_embeddings
 
             out_cond = self._t2i_predict_v(
@@ -2296,44 +2429,66 @@ class NEOChatModel(PreTrainedModel):
     ):
         assert self.concat_time_token_num == 0
         assert cfg_norm in ["cfg_zero_star", "global", "none", "channel"]
+        prompts = prompt if isinstance(prompt, list) else [prompt]
+        if not prompts:
+            raise ValueError("prompt batch must not be empty")
+        if batch_size < 1:
+            raise ValueError(f"batch_size must be positive, got {batch_size}")
+        if isinstance(prompt, list) and len(prompts) != batch_size:
+            raise ValueError(
+                f"batch_size={batch_size} does not match {len(prompts)} prompts"
+            )
+        if len(prompts) > 1 and think_mode:
+            raise ValueError(
+                "batched SenseNova-U1 generation does not support think_mode"
+            )
         self._notify_layer_offload_phase("prefix")
         merge_size = int(1 / self.downsample_ratio)
 
         self.config.t_eps = t_eps
-        # question_condition = f"Please generate an image based on the following description: {prompt}"
-        question_condition = f"{prompt}"
-        # question_condition += f"\nThe resolution of the image should be {image_size}"
-
         think_text = ""
         needs_cfg = cfg_scale > 1
 
         think_content = (
             "<think>\n" if think_mode else "<think>\n\n</think>\n\n" + IMG_START_TOKEN
         )
-        query_condition = self._build_t2i_query(
+        query_conditions = [
-            question_condition,
+            self._build_t2i_query(
+                item,
                 system_message=SYSTEM_MESSAGE_FOR_GEN,
                 append_text=think_content,
             )
+            for item in prompts
+        ]
+        query_condition = (
+            query_conditions[0] if len(query_conditions) == 1 else query_conditions
+        )
         query_uncondition = (
             self._build_t2i_query("", append_text=IMG_START_TOKEN)
             if needs_cfg
             else None
         )
 
-        input_ids_condition, indexes_condition, attention_mask_condition_prefix = (
+        (
-            self._build_t2i_text_inputs(tokenizer, query_condition)
+            input_ids_condition,
-        )
+            indexes_condition,
+            attention_mask_condition_prefix,
+            condition_key_valid_mask,
+            condition_prefix_lengths,
+        ) = self._build_t2i_text_inputs(tokenizer, query_condition)
         if query_uncondition is not None:
             (
                 input_ids_uncondition,
                 indexes_uncondition,
                 attention_mask_uncondition_prefix,
+                _,
+                uncondition_prefix_lengths,
             ) = self._build_t2i_text_inputs(tokenizer, query_uncondition)
         else:
             input_ids_uncondition = indexes_uncondition = (
                 attention_mask_uncondition_prefix
             ) = None
+            uncondition_prefix_lengths = None
 
         token_h = image_size[1] // (self.patch_size * merge_size)
         token_w = image_size[0] // (self.patch_size * merge_size)
@@ -2341,14 +2496,18 @@ class NEOChatModel(PreTrainedModel):
         indexes_image_condition = self._build_t2i_image_indexes(
             token_h,
             token_w,
-            indexes_condition.shape[1],
+            (
+                int(condition_prefix_lengths[0].item())
+                if len(prompts) == 1
+                else condition_prefix_lengths
+            ),
             device=input_ids_condition.device,
         )
         indexes_image_uncondition = (
             self._build_t2i_image_indexes(
                 token_h,
                 token_w,
-                indexes_uncondition.shape[1],
+                int(uncondition_prefix_lengths[0].item()),
                 device=input_ids_uncondition.device,
             )
             if indexes_uncondition is not None
@@ -2436,12 +2595,14 @@ class NEOChatModel(PreTrainedModel):
             past_key_values_condition,
             current_len=token_h * token_w,
             batch_size=batch_size,
+            prefix_lengths=condition_prefix_lengths,
         )
         if past_key_values_uncondition is not None:
             prepare_flash_kv_cache(
                 past_key_values_uncondition,
                 current_len=token_h * token_w,
                 batch_size=batch_size,
+                prefix_lengths=uncondition_prefix_lengths,
             )
 
         # init noise image tokens
@@ -2465,6 +2626,22 @@ class NEOChatModel(PreTrainedModel):
         )
 
         attention_mask_condition = {"full_attention": None}
+        if device.type == "npu" and batch_size > 1 and not npu_fia_available():
+            condition_key_valid_mask = condition_key_valid_mask.expand(batch_size, -1)
+            image_key_valid_mask = torch.ones(
+                (batch_size, token_h * token_w),
+                dtype=torch.bool,
+                device=device,
+            )
+            denoise_key_valid_mask = torch.cat(
+                [condition_key_valid_mask, image_key_valid_mask], dim=1
+            )
+            # Ascend SDPA requires an explicit query dimension.
+            attention_mask_condition["full_attention"] = (
+                denoise_key_valid_mask[:, None, None, :]
+                .expand(-1, -1, token_h * token_w, -1)
+                .contiguous()
+            )
         attention_mask_uncondition = {"full_attention": None}
 
         timesteps = torch.linspace(0.0, 1.0, num_steps + 1, device=device)
@@ -2472,6 +2649,16 @@ class NEOChatModel(PreTrainedModel):
             timesteps = self._apply_time_schedule(
                 timesteps, token_h * token_w, timestep_shift
             )
+        denoise_embeddings = None
+        if device.type == "npu":
+            denoise_embeddings = self.fm_modules["timestep_embedder"](timesteps[:-1])
+            if self.add_noise_scale_embedding:
+                noise_level = timesteps.new_tensor(
+                    [noise_scale / self.noise_scale_max_value]
+                )
+                denoise_embeddings = denoise_embeddings + self.fm_modules[
+                    "noise_scale_embedder"
+                ](noise_level)
 
         for step_i in range(num_steps):
             t = timesteps[step_i]
@@ -2486,18 +2673,20 @@ class NEOChatModel(PreTrainedModel):
                 gen_model=True,
                 grid_hw=grid_hw,
             ).view(batch_size, token_h * token_w, -1)
+            if denoise_embeddings is not None:
+                timestep_embeddings = denoise_embeddings[step_i].view(1, 1, -1)
+            else:
                 t_expanded = t.expand(batch_size * token_h * token_w)
-            timestep_embeddings = self.fm_modules["timestep_embedder"](t_expanded).view(
+                timestep_embeddings = self.fm_modules["timestep_embedder"](
-                batch_size, token_h * token_w, -1
+                    t_expanded
-            )
+                ).view(batch_size, token_h * token_w, -1)
                 if self.add_noise_scale_embedding:
                     noise_scale_tensor = torch.full_like(
                         t_expanded, noise_scale / self.noise_scale_max_value
                     )
-                noise_embeddings = self.fm_modules["noise_scale_embedder"](
+                    timestep_embeddings += self.fm_modules["noise_scale_embedder"](
                         noise_scale_tensor
                     ).view(batch_size, token_h * token_w, -1)
-                timestep_embeddings += noise_embeddings
             image_embeds = image_embeds + timestep_embeddings
 
             v_pred_condition = self._t2i_predict_v(

python/sglang/multimodal_gen/runtime/models/sensenova_u1/neo_unify/modeling_qwen3.py

@@ -5,12 +5,12 @@ from typing import Callable, Optional, Union
 
 import torch
 import torch._dynamo
+import torch.nn.functional as F
 from torch import nn
 from transformers import Qwen3Config
 from transformers.activations import ACT2FN
 from transformers.cache_utils import Cache, DynamicCache
 from transformers.generation import GenerationMixin
-from transformers.integrations import use_kernel_forward_from_hub
 from transformers.masking_utils import create_causal_mask
 from transformers.modeling_flash_attention_utils import FlashAttentionKwargs
 from transformers.modeling_layers import (
@@ -29,6 +29,9 @@ from transformers.processing_utils import Unpack
 from transformers.utils import TransformersKwargs, can_return_tuple
 from transformers.utils.deprecation import deprecate_kwarg
 
+from sglang.multimodal_gen.runtime.platforms import current_platform
+from sglang.srt.layers.layernorm import RMSNorm
+
 from .transformers_compat import (
     causal_mask_kwargs,
     model_input_compat,
@@ -55,6 +58,10 @@ _VALID_ATTN_BACKENDS = ("auto", "flash", "sdpa")
 _ATTN_BACKEND: str = "auto"
 
 
+def npu_fia_available() -> bool:
+    return hasattr(torch.ops.npu, "npu_fused_infer_attention_score")
+
+
 def set_attn_backend(backend: str) -> str:
     """Choose the attention kernel used by the Qwen3 layers at runtime.
 
@@ -92,7 +99,13 @@ def effective_attn_backend() -> str:
 
 
 def _sdpa_attn_func(
-    q, k, v, dropout_p: float = 0.0, softmax_scale=None, causal: bool = False
+    q,
+    k,
+    v,
+    dropout_p: float = 0.0,
+    softmax_scale=None,
+    causal: bool = False,
+    attention_mask: Optional[torch.Tensor] = None,
 ):
     """Drop-in SDPA fallback for ``flash_attn_func``.
 
@@ -127,6 +140,7 @@ def _sdpa_attn_func(
             q_bhsd,
             k_bhsd,
             v_bhsd,
+            attn_mask=attention_mask,
             dropout_p=dropout_p,
             is_causal=causal,
             scale=softmax_scale,
@@ -138,6 +152,7 @@ def _sdpa_attn_func(
                 q_bhsd,
                 k_bhsd,
                 v_bhsd,
+                attn_mask=attention_mask,
                 dropout_p=dropout_p,
                 is_causal=causal,
             )
@@ -146,6 +161,7 @@ def _sdpa_attn_func(
                 q_bhsd,
                 k_bhsd,
                 v_bhsd,
+                attn_mask=attention_mask,
                 dropout_p=dropout_p,
                 is_causal=causal,
             )
@@ -153,37 +169,167 @@ def _sdpa_attn_func(
 
 
 def _flash_or_sdpa(
-    q, k, v, dropout_p: float = 0.0, softmax_scale=None, causal: bool = False
+    q,
+    k,
+    v,
+    dropout_p: float = 0.0,
+    softmax_scale=None,
+    causal: bool = False,
+    attention_mask: Optional[torch.Tensor] = None,
+    actual_seq_lengths_kv: Optional[list[int]] = None,
+    kv_padding_size: Optional[torch.Tensor] = None,
+    input_layout: str = "BSND",
 ):
     backend = effective_attn_backend()
+    if (
+        q.device.type == "npu"
+        and not causal
+        and dropout_p == 0.0
+        and actual_seq_lengths_kv is not None
+        and npu_fia_available()
+    ):
+        if input_layout == "BNSD":
+            q_bhsd, k_bhsd, v_bhsd = q, k, v
+            batch_size, num_heads, query_length, _ = q.shape
+            num_key_value_heads = k.shape[1]
+        elif input_layout == "BSND":
+            q_bhsd = q.transpose(1, 2).contiguous()
+            k_bhsd = k.transpose(1, 2).contiguous()
+            v_bhsd = v.transpose(1, 2).contiguous()
+            batch_size, query_length, num_heads, _ = q.shape
+            num_key_value_heads = k.shape[2]
+        else:
+            raise ValueError(f"Unsupported attention input layout: {input_layout}")
+        out, _ = torch.ops.npu.npu_fused_infer_attention_score(
+            q_bhsd,
+            k_bhsd,
+            v_bhsd,
+            actual_seq_lengths=[query_length] * batch_size,
+            actual_seq_lengths_kv=actual_seq_lengths_kv,
+            kv_padding_size=kv_padding_size,
+            num_heads=num_heads,
+            num_key_value_heads=num_key_value_heads,
+            scale=q.shape[-1] ** -0.5 if softmax_scale is None else softmax_scale,
+            input_layout="BNSD",
+            sparse_mode=0,
+        )
+        return out.transpose(1, 2).contiguous()
+    if input_layout != "BSND":
+        raise RuntimeError("BNSD attention input requires the NPU FIA path")
+    if actual_seq_lengths_kv is not None:
+        batch_size, query_length = q.shape[:2]
+        padded_key_length = k.shape[1]
+        prefix_width = padded_key_length - query_length
+        if len(actual_seq_lengths_kv) != batch_size:
+            raise ValueError(
+                f"Expected {batch_size} KV lengths, got {len(actual_seq_lengths_kv)}"
+            )
+        if all(length == padded_key_length for length in actual_seq_lengths_kv):
+            return _flash_or_sdpa(
+                q,
+                k,
+                v,
+                dropout_p=dropout_p,
+                softmax_scale=softmax_scale,
+                causal=causal,
+                attention_mask=attention_mask,
+            )
+        outputs = []
+        for batch_index, total_length in enumerate(actual_seq_lengths_kv):
+            prefix_length = total_length - query_length
+            if prefix_length < 0 or prefix_length > prefix_width:
+                raise ValueError(
+                    f"KV length {total_length} is incompatible with query length "
+                    f"{query_length} and padded key length {padded_key_length}"
+                )
+            if total_length == padded_key_length:
+                compact_k = k[batch_index : batch_index + 1]
+                compact_v = v[batch_index : batch_index + 1]
+            else:
+                compact_k = torch.cat(
+                    (
+                        k[batch_index : batch_index + 1, :prefix_length],
+                        k[batch_index : batch_index + 1, prefix_width:],
+                    ),
+                    dim=1,
+                )
+                compact_v = torch.cat(
+                    (
+                        v[batch_index : batch_index + 1, :prefix_length],
+                        v[batch_index : batch_index + 1, prefix_width:],
+                    ),
+                    dim=1,
+                )
+            outputs.append(
+                _flash_or_sdpa(
+                    q[batch_index : batch_index + 1],
+                    compact_k,
+                    compact_v,
+                    dropout_p=dropout_p,
+                    softmax_scale=softmax_scale,
+                    causal=causal,
+                    attention_mask=attention_mask,
+                )
+            )
+        return torch.cat(outputs, dim=0)
     # flash-attn ships CUDA kernels only. On XPU / CPU we transparently fall
     # back to SDPA even if the user asked for ``flash`` — the alternative
     # (crashing on first forward) is worse, and ``set_attn_backend('flash')``
     # already guarded against the "package missing" case.
-    if backend == "flash" and q.device.type == "cuda":
+    if backend == "flash" and q.device.type == "cuda" and attention_mask is None:
         return flash_attn_func(
             q, k, v, dropout_p=dropout_p, softmax_scale=softmax_scale, causal=causal
         )
     return _sdpa_attn_func(
-        q, k, v, dropout_p=dropout_p, softmax_scale=softmax_scale, causal=causal
+        q,
+        k,
+        v,
+        dropout_p=dropout_p,
+        softmax_scale=softmax_scale,
+        causal=causal,
+        attention_mask=attention_mask,
     )
 
 
-def create_block_causal_mask(index: torch.Tensor):
+def position_ids_from_indexes(indexes: torch.Tensor, coordinate: int) -> torch.Tensor:
-    """
+    """Return one coordinate as ``[batch, sequence]`` position IDs."""
-    index: (L)
+    if indexes.ndim == 2:
-    return: (1, 1, L, L) block-wise causal attention mask
+        return indexes[coordinate].unsqueeze(0)
-    """
+    if indexes.ndim == 3:
-    L = index.size(0)
+        return indexes[:, coordinate]
-    idx_i = index.unsqueeze(1).expand(L, L)
+    raise ValueError(f"indexes must have 2 or 3 dimensions, got {indexes.ndim}")
-    idx_j = index.unsqueeze(0).expand(L, L)
 
-    arange = torch.arange(L, device=index.device)
-    mask = (idx_j == idx_i) | (arange.unsqueeze(0) <= arange.unsqueeze(1))
 
-    return torch.where(
+def create_block_causal_mask(
-        mask[None, None, :, :] > 0, torch.tensor(0.0), torch.tensor(float("-inf"))
+    index: torch.Tensor, key_valid_mask: Optional[torch.Tensor] = None
+):
+    """
+    index: (L) or (B, L)
+    key_valid_mask: optional (B, L), where True marks a real token
+    return: (B, 1, L, L) block-wise causal attention mask
+    """
+    if index.ndim == 1:
+        index = index.unsqueeze(0)
+    if index.ndim != 2:
+        raise ValueError(f"index must have 1 or 2 dimensions, got {index.ndim}")
+
+    batch_size, seq_len = index.shape
+    idx_i = index.unsqueeze(2)
+    idx_j = index.unsqueeze(1)
+
+    arange = torch.arange(seq_len, device=index.device)
+    mask = (idx_j == idx_i) | (arange.view(1, 1, -1) <= arange.view(1, -1, 1))
+    if key_valid_mask is not None:
+        if key_valid_mask.shape != (batch_size, seq_len):
+            raise ValueError(
+                "key_valid_mask must match the batched index shape; "
+                f"got {tuple(key_valid_mask.shape)} and {(batch_size, seq_len)}"
             )
+        mask = mask & key_valid_mask.to(torch.bool).unsqueeze(1)
+
+    output = torch.zeros(mask.shape, dtype=torch.float32, device=index.device)
+    output.masked_fill_(~mask, float("-inf"))
+    return output.unsqueeze(1)
 
 
 def visualize_mask(mask: torch.Tensor, i: int = 0, j: int = 12):
@@ -196,25 +342,13 @@ def visualize_mask(mask: torch.Tensor, i: int = 0, j: int = 12):
         print(" ".join(map(str, row)))
 
 
-@use_kernel_forward_from_hub("RMSNorm")
+def make_qwen3_rms_norm(hidden_size: int, eps: float) -> RMSNorm:
-class Qwen3RMSNorm(nn.Module):
+    return RMSNorm(
-    def __init__(self, hidden_size, eps: float = 1e-6) -> None:
+        hidden_size,
-        """
+        eps=eps,
-        Qwen3RMSNorm is equivalent to T5LayerNorm
+        cast_x_before_out_mul=True,
-        """
+        force_native=not current_platform.is_npu(),
-        super().__init__()
+    )
-        self.weight = nn.Parameter(torch.ones(hidden_size))
-        self.variance_epsilon = eps
-
-    def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
-        input_dtype = hidden_states.dtype
-        hidden_states = hidden_states.to(torch.float32)
-        variance = hidden_states.pow(2).mean(-1, keepdim=True)
-        hidden_states = hidden_states * torch.rsqrt(variance + self.variance_epsilon)
-        return self.weight * hidden_states.to(input_dtype)
-
-    def extra_repr(self):
-        return f"{tuple(self.weight.shape)}, eps={self.variance_epsilon}"
 
 
 class Qwen3MLP(nn.Module):
@@ -227,8 +361,45 @@ class Qwen3MLP(nn.Module):
         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]
+        self._npu_gate_up_weight = None
+
+    def _pack_npu_gate_up_weights(self) -> torch.Tensor:
+        reference = self.gate_proj.weight
+        packed = self._npu_gate_up_weight
+        if (
+            packed is not None
+            and packed.device == reference.device
+            and packed.dtype == reference.dtype
+            and packed.untyped_storage().data_ptr()
+            == reference.untyped_storage().data_ptr()
+        ):
+            return packed
+
+        with torch.no_grad():
+            packed = torch.cat(
+                [self.gate_proj.weight, self.up_proj.weight], dim=0
+            ).contiguous()
+            self.gate_proj.weight.set_(packed[: self.intermediate_size])
+            self.up_proj.weight.set_(packed[self.intermediate_size :])
+        self._npu_gate_up_weight = packed
+        return packed
+
+    def _use_npu_fused_mlp(self, x: torch.Tensor) -> bool:
+        if (
+            x.device.type != "npu"
+            or self.training
+            or torch.is_grad_enabled()
+            or x.dtype != torch.bfloat16
+            or self.gate_proj.weight.dtype != x.dtype
+            or self.config.hidden_act != "silu"
+        ):
+            return False
+        return hasattr(torch.ops.npu, "npu_swiglu")
 
     def forward(self, x):
+        if self._use_npu_fused_mlp(x):
+            gate_up = F.linear(x, self._pack_npu_gate_up_weights())
+            return self.down_proj(torch.ops.npu.npu_swiglu(gate_up))
         down_proj = self.down_proj(self.act_fn(self.gate_proj(x)) * self.up_proj(x))
         return down_proj
 
@@ -462,23 +633,29 @@ class Qwen3Attention(nn.Module):
             bias=config.attention_bias,
         )
 
-        self.q_norm = Qwen3RMSNorm(
+        self.q_norm = make_qwen3_rms_norm(
             self.head_dim // 2, eps=config.rms_norm_eps
         )  # unlike olmo, only on the head dim!
-        self.q_norm_mot_gen = Qwen3RMSNorm(self.head_dim // 2, eps=config.rms_norm_eps)
+        self.q_norm_mot_gen = make_qwen3_rms_norm(
-        self.q_norm_hw = Qwen3RMSNorm(self.head_dim // 2, eps=config.rms_norm_eps)
+            self.head_dim // 2, eps=config.rms_norm_eps
-        self.q_norm_hw_mot_gen = Qwen3RMSNorm(
+        )
+        self.q_norm_hw = make_qwen3_rms_norm(
+            self.head_dim // 2, eps=config.rms_norm_eps
+        )
+        self.q_norm_hw_mot_gen = make_qwen3_rms_norm(
             self.head_dim // 2, eps=config.rms_norm_eps
         )
 
-        self.k_norm = Qwen3RMSNorm(
+        self.k_norm = make_qwen3_rms_norm(
             self.head_dim // 2, eps=config.rms_norm_eps
         )  # thus post q_norm does not need reshape
-        self.k_norm_mot_gen = Qwen3RMSNorm(self.head_dim // 2, eps=config.rms_norm_eps)
+        self.k_norm_mot_gen = make_qwen3_rms_norm(
-        self.k_norm_hw = Qwen3RMSNorm(
+            self.head_dim // 2, eps=config.rms_norm_eps
+        )
+        self.k_norm_hw = make_qwen3_rms_norm(
             self.head_dim // 2, eps=config.rms_norm_eps
         )  # thus post q_norm does not need reshape
-        self.k_norm_hw_mot_gen = Qwen3RMSNorm(
+        self.k_norm_hw_mot_gen = make_qwen3_rms_norm(
             self.head_dim // 2, eps=config.rms_norm_eps
         )
 
@@ -530,17 +707,23 @@ class Qwen3Attention(nn.Module):
 
         value_states = self.v_proj(hidden_states).view(hidden_shape).transpose(1, 2)
 
-        cos_t, sin_t = self.rotary_emb(hidden_states, indexes[0].unsqueeze(0))
+        cos_t, sin_t = self.rotary_emb(
+            hidden_states, position_ids_from_indexes(indexes, 0)
+        )
         query_states_t, key_states_t = apply_rotary_pos_emb(
             query_states_t, key_states_t, cos_t, sin_t
         )
 
-        cos_h, sin_h = self.rotary_emb_hw(hidden_states, indexes[1].unsqueeze(0))
+        cos_h, sin_h = self.rotary_emb_hw(
+            hidden_states, position_ids_from_indexes(indexes, 1)
+        )
         query_states_h, key_states_h = apply_rotary_pos_emb(
             query_states_h, key_states_h, cos_h, sin_h
         )
 
-        cos_w, sin_w = self.rotary_emb_hw(hidden_states, indexes[2].unsqueeze(0))
+        cos_w, sin_w = self.rotary_emb_hw(
+            hidden_states, position_ids_from_indexes(indexes, 2)
+        )
         query_states_w, key_states_w = apply_rotary_pos_emb(
             query_states_w, key_states_w, cos_w, sin_w
         )
@@ -705,17 +888,23 @@ class Qwen3Attention(nn.Module):
         )  # [B,H,S,D]
 
         # RoPE
-        cos_t, sin_t = self.rotary_emb(hidden_states, indexes[0].unsqueeze(0))
+        cos_t, sin_t = self.rotary_emb(
+            hidden_states, position_ids_from_indexes(indexes, 0)
+        )
         query_states_t, key_states_t = apply_rotary_pos_emb(
             query_states_t, key_states_t, cos_t, sin_t
         )
 
-        cos_h, sin_h = self.rotary_emb_hw(hidden_states, indexes[1].unsqueeze(0))
+        cos_h, sin_h = self.rotary_emb_hw(
+            hidden_states, position_ids_from_indexes(indexes, 1)
+        )
         query_states_h, key_states_h = apply_rotary_pos_emb(
             query_states_h, key_states_h, cos_h, sin_h
         )
 
-        cos_w, sin_w = self.rotary_emb_hw(hidden_states, indexes[2].unsqueeze(0))
+        cos_w, sin_w = self.rotary_emb_hw(
+            hidden_states, position_ids_from_indexes(indexes, 2)
+        )
         query_states_w, key_states_w = apply_rotary_pos_emb(
             query_states_w, key_states_w, cos_w, sin_w
         )
@@ -736,8 +925,45 @@ class Qwen3Attention(nn.Module):
         #   current image tokens attend to [prefix + current image tokens]
         #   fully bidirectional inside current block => causal=False
         # ------------------------------------------------------------------
-        if attention_mask is None:
+        key_padding_mask = (
-            # Convert current q/k/v to flash layout [B, S, H, D]
+            attention_mask is not None
+            and attention_mask.ndim == 4
+            and (attention_mask.shape[-2] == 1 or attention_mask.dtype == torch.bool)
+        )
+        if attention_mask is None or key_padding_mask:
+            actual_seq_lengths_kv = None
+            kv_padding_size = None
+            input_layout = "BSND"
+            layer = (
+                past_key_values.layers[self.layer_idx]
+                if past_key_values is not None and not update_cache
+                else None
+            )
+            use_bnsd_cache = (
+                layer is not None
+                and getattr(layer, "flash_cache_layout", None) == "BNSD"
+                and getattr(layer, "flash_k_cache", None) is not None
+                and getattr(layer, "flash_v_cache", None) is not None
+            )
+
+            if use_bnsd_cache:
+                q = query_states
+                k_cur = key_states
+                v_cur = value_states
+                prefix_len = layer.flash_prefix_len
+                cur_len = k_cur.shape[2]
+                layer.flash_k_cache[:, :, prefix_len : prefix_len + cur_len].copy_(
+                    k_cur
+                )
+                layer.flash_v_cache[:, :, prefix_len : prefix_len + cur_len].copy_(
+                    v_cur
+                )
+                k = layer.flash_k_cache[:, :, : prefix_len + cur_len]
+                v = layer.flash_v_cache[:, :, : prefix_len + cur_len]
+                actual_seq_lengths_kv = layer.flash_actual_seq_lengths_kv
+                kv_padding_size = layer.flash_kv_padding_size
+                input_layout = "BNSD"
+            else:
                 q = query_states.transpose(1, 2).contiguous()
                 k_cur = key_states.transpose(1, 2).contiguous()
                 v_cur = value_states.transpose(1, 2).contiguous()
@@ -752,34 +978,29 @@ class Qwen3Attention(nn.Module):
                         k = key_states.transpose(1, 2).contiguous()
                         v = value_states.transpose(1, 2).contiguous()
                     else:
-                    # Optimized path:
-                    # use preallocated flash_k_cache / flash_v_cache
-                    layer = past_key_values.layers[self.layer_idx]
-
                         if (
-                        hasattr(layer, "flash_k_cache")
+                            getattr(layer, "flash_k_cache", None) is not None
-                        and layer.flash_k_cache is not None
+                            and getattr(layer, "flash_v_cache", None) is not None
-                        and hasattr(layer, "flash_v_cache")
-                        and layer.flash_v_cache is not None
                         ):
                             prefix_len = layer.flash_prefix_len
                             cur_len = k_cur.shape[1]
-
+                            layer.flash_k_cache[
-                        # overwrite current segment in-place
+                                :, prefix_len : prefix_len + cur_len
-                        layer.flash_k_cache[:, prefix_len : prefix_len + cur_len].copy_(
+                            ].copy_(k_cur)
-                            k_cur
+                            layer.flash_v_cache[
-                        )
+                                :, prefix_len : prefix_len + cur_len
-                        layer.flash_v_cache[:, prefix_len : prefix_len + cur_len].copy_(
+                            ].copy_(v_cur)
-                            v_cur
-                        )
-
                             k = layer.flash_k_cache[:, : prefix_len + cur_len]
                             v = layer.flash_v_cache[:, : prefix_len + cur_len]
+                            actual_seq_lengths_kv = getattr(
+                                layer, "flash_actual_seq_lengths_kv", None
+                            )
+                            kv_padding_size = getattr(
+                                layer, "flash_kv_padding_size", None
+                            )
                         else:
-                        # fallback if user forgot to prepare flash cache
+                            # fallback if the cache was not prepared
-                        layer = past_key_values.layers[self.layer_idx]
                             past_k, past_v = layer.keys, layer.values
-
                             if past_k is not None:
                                 past_k = past_k.transpose(1, 2).contiguous()
                                 past_v = past_v.transpose(1, 2).contiguous()
@@ -806,6 +1027,10 @@ class Qwen3Attention(nn.Module):
                 dropout_p=0.0 if not self.training else self.attention_dropout,
                 softmax_scale=self.scaling,
                 causal=False,
+                attention_mask=attention_mask,
+                actual_seq_lengths_kv=actual_seq_lengths_kv,
+                kv_padding_size=kv_padding_size,
+                input_layout=input_layout,
             )  # [B, S_q, H_q, D]
 
             attn_output = attn_output.reshape(*input_shape, -1).contiguous()
@@ -982,17 +1207,23 @@ class Qwen3Attention(nn.Module):
             )
         value_states = value_states.view(hidden_shape).transpose(1, 2)
 
-        cos_t, sin_t = self.rotary_emb(hidden_states, indexes[0].unsqueeze(0))
+        cos_t, sin_t = self.rotary_emb(
+            hidden_states, position_ids_from_indexes(indexes, 0)
+        )
         query_states_t, key_states_t = apply_rotary_pos_emb(
             query_states_t, key_states_t, cos_t, sin_t
         )
 
-        cos_h, sin_h = self.rotary_emb_hw(hidden_states, indexes[1].unsqueeze(0))
+        cos_h, sin_h = self.rotary_emb_hw(
+            hidden_states, position_ids_from_indexes(indexes, 1)
+        )
         query_states_h, key_states_h = apply_rotary_pos_emb(
             query_states_h, key_states_h, cos_h, sin_h
         )
 
-        cos_w, sin_w = self.rotary_emb_hw(hidden_states, indexes[2].unsqueeze(0))
+        cos_w, sin_w = self.rotary_emb_hw(
+            hidden_states, position_ids_from_indexes(indexes, 2)
+        )
         query_states_w, key_states_w = apply_rotary_pos_emb(
             query_states_w, key_states_w, cos_w, sin_w
         )
@@ -1065,14 +1296,16 @@ class Qwen3DecoderLayer(GradientCheckpointingLayer):
 
         self.mlp = Qwen3MLP(config)
         self.mlp_mot_gen = Qwen3MLP(config)
-        self.input_layernorm = Qwen3RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
+        self.input_layernorm = make_qwen3_rms_norm(
-        self.input_layernorm_mot_gen = Qwen3RMSNorm(
             config.hidden_size, eps=config.rms_norm_eps
         )
-        self.post_attention_layernorm = Qwen3RMSNorm(
+        self.input_layernorm_mot_gen = make_qwen3_rms_norm(
             config.hidden_size, eps=config.rms_norm_eps
         )
-        self.post_attention_layernorm_mot_gen = Qwen3RMSNorm(
+        self.post_attention_layernorm = make_qwen3_rms_norm(
+            config.hidden_size, eps=config.rms_norm_eps
+        )
+        self.post_attention_layernorm_mot_gen = make_qwen3_rms_norm(
             config.hidden_size, eps=config.rms_norm_eps
         )
         self.attention_type = config.layer_types[layer_idx]
@@ -1288,8 +1521,10 @@ class Qwen3Model(Qwen3PreTrainedModel):
                 for layer_idx in range(config.num_hidden_layers)
             ]
         )
-        self.norm = Qwen3RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
+        self.norm = make_qwen3_rms_norm(config.hidden_size, eps=config.rms_norm_eps)
-        self.norm_mot_gen = Qwen3RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
+        self.norm_mot_gen = make_qwen3_rms_norm(
+            config.hidden_size, eps=config.rms_norm_eps
+        )
 
         self.gradient_checkpointing = False
         self.has_sliding_layers = "sliding_attention" in self.config.layer_types
@@ -1375,11 +1610,13 @@ class Qwen3Model(Qwen3PreTrainedModel):
                 )
             else:
                 causal_mask_mapping = {
-                    "full_attention": create_block_causal_mask(indexes[0]),
+                    "full_attention": create_block_causal_mask(
+                        position_ids_from_indexes(indexes, 0)
+                    ),
                 }
-                self.current_index = indexes[0].max()
+                self.current_index = position_ids_from_indexes(indexes, 0).max()
         else:
-            self.current_index = indexes[0].max()
+            self.current_index = position_ids_from_indexes(indexes, 0).max()
             # raise NotImplementedError('not isinstance(causal_mask_mapping := attention_mask, dict)')
 
             # The sliding window alternating layers are not always activated depending on the config

python/sglang/multimodal_gen/runtime/models/sensenova_u1/neo_unify/modeling_qwen3_moe.py

@@ -21,8 +21,9 @@ from transformers.utils.deprecation import deprecate_kwarg
 from .configuration_neo_chat import NEOMoELLMConfig
 from .modeling_qwen3 import (
     Qwen3Attention,
-    Qwen3RMSNorm,
     create_block_causal_mask,
+    make_qwen3_rms_norm,
+    position_ids_from_indexes,
 )
 from .transformers_compat import (
     causal_mask_kwargs,
@@ -198,14 +199,16 @@ class Qwen3MoeDecoderLayer(GradientCheckpointingLayer):
             ),
         )
 
-        self.input_layernorm = Qwen3RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
+        self.input_layernorm = make_qwen3_rms_norm(
-        self.input_layernorm_mot_gen = Qwen3RMSNorm(
             config.hidden_size, eps=config.rms_norm_eps
         )
-        self.post_attention_layernorm = Qwen3RMSNorm(
+        self.input_layernorm_mot_gen = make_qwen3_rms_norm(
             config.hidden_size, eps=config.rms_norm_eps
         )
-        self.post_attention_layernorm_mot_gen = Qwen3RMSNorm(
+        self.post_attention_layernorm = make_qwen3_rms_norm(
+            config.hidden_size, eps=config.rms_norm_eps
+        )
+        self.post_attention_layernorm_mot_gen = make_qwen3_rms_norm(
             config.hidden_size, eps=config.rms_norm_eps
         )
         self.attention_type = config.layer_types[layer_idx]
@@ -422,8 +425,10 @@ class Qwen3MoeModel(Qwen3MoePreTrainedModel):
                 for layer_idx in range(config.num_hidden_layers)
             ]
         )
-        self.norm = Qwen3RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
+        self.norm = make_qwen3_rms_norm(config.hidden_size, eps=config.rms_norm_eps)
-        self.norm_mot_gen = Qwen3RMSNorm(config.hidden_size, eps=config.rms_norm_eps)
+        self.norm_mot_gen = make_qwen3_rms_norm(
+            config.hidden_size, eps=config.rms_norm_eps
+        )
 
         self.gradient_checkpointing = False
         self.has_sliding_layers = "sliding_attention" in self.config.layer_types
@@ -499,11 +504,13 @@ class Qwen3MoeModel(Qwen3MoePreTrainedModel):
                 )
             else:
                 causal_mask_mapping = {
-                    "full_attention": create_block_causal_mask(indexes[0]),
+                    "full_attention": create_block_causal_mask(
+                        position_ids_from_indexes(indexes, 0)
+                    ),
                 }
-                self.current_index = indexes[0].max()
+                self.current_index = position_ids_from_indexes(indexes, 0).max()
         else:
-            self.current_index = indexes[0].max()
+            self.current_index = position_ids_from_indexes(indexes, 0).max()
 
         hidden_states = inputs_embeds
 

python/sglang/multimodal_gen/runtime/pipelines_core/stages/model_specific_stages/sensenova_u1/stages/generation.py

@@ -71,7 +71,37 @@ class SenseNovaU1GenerationStage(PipelineStage):
                 "SenseNova-U1 expects output expansion before generation; "
                 f"got num_outputs_per_prompt={batch.num_outputs_per_prompt}."
             )
-        seed = batch.seed[0] if isinstance(batch.seed, list) else int(batch.seed)
+        prompts = batch.prompt if isinstance(batch.prompt, list) else [batch.prompt]
+        batch_size = len(prompts)
+        if batch_size == 0:
+            raise ValueError(
+                "SenseNova-U1 dynamic batch must contain at least one prompt"
+            )
+        if batch_size > 1 and options.think_mode:
+            raise ValueError(
+                "SenseNova-U1 dynamic batching does not support think_mode"
+            )
+
+        dynamic_seeds = batch.extra.get("dynamic_batch_seeds")
+        if dynamic_seeds is None:
+            dynamic_seeds = batch.seed if isinstance(batch.seed, list) else [batch.seed]
+        elif not isinstance(dynamic_seeds, list):
+            dynamic_seeds = [dynamic_seeds]
+        seeds = []
+        for seed in dynamic_seeds:
+            if isinstance(seed, list):
+                if len(seed) != 1:
+                    raise ValueError(
+                        "SenseNova-U1 dynamic batching requires one seed per request"
+                    )
+                seed = seed[0]
+            seeds.append(int(seed))
+        if len(seeds) != batch_size:
+            raise ValueError(
+                "SenseNova-U1 dynamic batch requires one seed per prompt; "
+                f"got {len(seeds)} seeds for {batch_size} prompts"
+            )
+        seed = seeds[0] if batch_size == 1 else seeds
 
         out = self.model.t2i_generate(
             self.tokenizer,
@@ -83,7 +113,7 @@ class SenseNovaU1GenerationStage(PipelineStage):
             enable_timestep_shift=options.enable_timestep_shift,
             cfg_interval=options.cfg_interval,
             num_steps=int(batch.num_inference_steps),
-            batch_size=1,
+            batch_size=batch_size,
             t_eps=options.t_eps,
             think_mode=options.think_mode,
             seed=seed,

python/sglang/multimodal_gen/test/unit/test_sensenova_u1.py

@@ -1,10 +1,14 @@
 # SPDX-License-Identifier: Apache-2.0
 import asyncio
 import json
+import time
+from collections import deque
 from types import SimpleNamespace
 
 import pytest
 import torch
+import torch.nn.functional as F
+from transformers.cache_utils import DynamicCache
 
 from sglang.multimodal_gen.configs.pipeline_configs.sensenova_u1 import (
     SenseNovaU1PipelineConfig,
@@ -26,6 +30,10 @@ from sglang.multimodal_gen.runtime.entrypoints.openai.utils import (
     process_generation_batch,
 )
 from sglang.multimodal_gen.runtime.managers.gpu_worker import GPUWorker
+from sglang.multimodal_gen.runtime.managers.scheduler import Scheduler
+from sglang.multimodal_gen.runtime.models.sensenova_u1.neo_unify.configuration_neo_chat import (
+    NEOLLMConfig,
+)
 from sglang.multimodal_gen.runtime.models.sensenova_u1.neo_unify.configuration_neo_vit import (
     NEOVisionConfig,
 )
@@ -33,7 +41,20 @@ from sglang.multimodal_gen.runtime.models.sensenova_u1.neo_unify.conversation im
     get_conv_template,
 )
 from sglang.multimodal_gen.runtime.models.sensenova_u1.neo_unify.modeling_neo_chat import (
+    NEOChatModel,
+    _copy_right_aligned_prefix_bnsd,
     _randn_with_seed,
+    prepare_flash_kv_cache,
+)
+from sglang.multimodal_gen.runtime.models.sensenova_u1.neo_unify.modeling_qwen3 import (
+    Qwen3Attention,
+    Qwen3MLP,
+    _flash_or_sdpa,
+    _sdpa_attn_func,
+    create_block_causal_mask,
+    make_qwen3_rms_norm,
+    npu_fia_available,
+    position_ids_from_indexes,
 )
 from sglang.multimodal_gen.runtime.pipelines_core.executors.pipeline_executor import (
     PipelineExecutor,
@@ -48,6 +69,7 @@ from sglang.multimodal_gen.runtime.pipelines_core.stages.model_specific_stages.s
 from sglang.multimodal_gen.runtime.platforms import current_platform
 from sglang.multimodal_gen.runtime.server_args.server_args import ServerArgs
 from sglang.multimodal_gen.runtime.utils.perf_logger import MemorySnapshot
+from sglang.srt.layers.layernorm import RMSNorm
 
 
 class _FakeSenseNovaModel:
@@ -56,7 +78,7 @@ class _FakeSenseNovaModel:
 
     def t2i_generate(self, tokenizer, prompt, **kwargs):
         self.call_kwargs = {"tokenizer": tokenizer, "prompt": prompt, **kwargs}
-        return torch.tensor(
+        sample = torch.tensor(
             [
                 [
                     [[-1.0, 0.0], [0.5, 1.0]],
@@ -65,6 +87,17 @@ class _FakeSenseNovaModel:
                 ]
             ]
         )
+        return sample.repeat(kwargs["batch_size"], 1, 1, 1)
+
+
+class _FakeTokenizer:
+    pad_token_id = None
+    eos_token_id = 2
+
+    def __call__(self, text, return_tensors):
+        del return_tensors
+        token_count = len(text.split()) + 1
+        return {"input_ids": torch.arange(1, token_count + 1).unsqueeze(0)}
 
 
 class _RecordingTraceContext:
@@ -188,6 +221,299 @@ def test_sensenova_u1_randn_fallback_preserves_cpu_rng(monkeypatch):
     assert torch.equal(torch.get_rng_state(), rng_state)
 
 
+def test_sensenova_u1_randn_supports_per_sample_seeds():
+    actual = _randn_with_seed(
+        (2, 3, 4), device=torch.device("cpu"), dtype=torch.float32, seed=[7, 19]
+    )
+    expected = torch.cat(
+        [
+            _randn_with_seed(
+                (1, 3, 4),
+                device=torch.device("cpu"),
+                dtype=torch.float32,
+                seed=seed,
+            )
+            for seed in (7, 19)
+        ]
+    )
+
+    assert torch.equal(actual, expected)
+
+
+def test_sensenova_u1_builds_padded_batched_text_inputs():
+    model = SimpleNamespace(device=torch.device("cpu"))
+
+    input_ids, indexes, attention_mask, valid_mask, prefix_lengths = (
+        NEOChatModel._build_t2i_text_inputs(
+            model, _FakeTokenizer(), ["short", "a much longer prompt"]
+        )
+    )
+
+    assert input_ids.shape == (2, 5)
+    assert indexes.shape == (2, 3, 5)
+    assert prefix_lengths.tolist() == [2, 5]
+    assert valid_mask.tolist() == [
+        [True, True, False, False, False],
+        [True, True, True, True, True],
+    ]
+    mask = attention_mask["full_attention"]
+    assert mask.shape == (2, 1, 5, 5)
+    assert torch.isneginf(mask[0, :, :, 2:]).all()
+    assert torch.isfinite(mask[0, :, :, :2]).any()
+
+
+def test_sensenova_u1_position_indexes_support_batched_inputs():
+    indexes = torch.tensor(
+        [
+            [[0, 1], [0, 0], [0, 0]],
+            [[4, 4], [0, 1], [0, 0]],
+        ]
+    )
+
+    assert torch.equal(position_ids_from_indexes(indexes, 0), indexes[:, 0])
+    assert torch.equal(
+        position_ids_from_indexes(indexes[0], 1), indexes[0, 1].unsqueeze(0)
+    )
+
+
+def test_sensenova_u1_singleton_text_matches_valid_batched_tokens():
+    model = SimpleNamespace(device=torch.device("cpu"))
+    tokenizer = _FakeTokenizer()
+    batched = NEOChatModel._build_t2i_text_inputs(
+        model, tokenizer, ["short", "a much longer prompt"]
+    )
+    for i, prompt in enumerate(["short", "a much longer prompt"]):
+        single = NEOChatModel._build_t2i_text_inputs(model, tokenizer, prompt)
+        length = single[0].shape[1]
+        assert torch.equal(batched[0][i, :length], single[0][0])
+        assert torch.equal(batched[1][i, :, :length], single[1])
+        assert torch.equal(
+            batched[2]["full_attention"][i, :, :length, :length],
+            single[2]["full_attention"][0],
+        )
+
+
+def test_sensenova_u1_block_causal_mask_rejects_padded_keys():
+    indexes = torch.tensor([[0, 1, 2], [0, 1, 2]])
+    valid = torch.tensor([[True, True, False], [True, True, True]])
+
+    mask = create_block_causal_mask(indexes, valid)
+
+    assert mask.shape == (2, 1, 3, 3)
+    assert torch.isneginf(mask[0, :, :, 2]).all()
+    assert mask[1, 0, 2, 2] == 0
+
+
+def test_sensenova_u1_builds_per_sample_image_indexes():
+    indexes = NEOChatModel._build_t2i_image_indexes(
+        SimpleNamespace(),
+        token_h=2,
+        token_w=2,
+        text_len=torch.tensor([2, 5]),
+        device=torch.device("cpu"),
+    )
+
+    assert indexes.shape == (2, 3, 4)
+    assert indexes[:, 0].tolist() == [[2, 2, 2, 2], [5, 5, 5, 5]]
+    assert indexes[:, 1].tolist() == [[0, 0, 1, 1], [0, 0, 1, 1]]
+    assert indexes[:, 2].tolist() == [[0, 1, 0, 1], [0, 1, 0, 1]]
+
+
+def test_sensenova_u1_compacts_variable_length_kv_before_attention():
+    generator = torch.Generator().manual_seed(29)
+    q = torch.randn(2, 3, 4, 8, generator=generator)
+    k = torch.randn(2, 8, 2, 8, generator=generator)
+    v = torch.randn(2, 8, 2, 8, generator=generator)
+    actual = _flash_or_sdpa(
+        q,
+        k,
+        v,
+        actual_seq_lengths_kv=[5, 8],
+    )
+
+    expected_short = _sdpa_attn_func(
+        q[:1],
+        torch.cat((k[:1, :2], k[:1, 5:]), dim=1),
+        torch.cat((v[:1, :2], v[:1, 5:]), dim=1),
+    )
+    expected_long = _sdpa_attn_func(q[1:], k[1:], v[1:])
+    torch.testing.assert_close(actual, torch.cat((expected_short, expected_long)))
+
+
+def test_sensenova_u1_sdpa_masks_padded_prefix_keys():
+    q = torch.tensor([[[[1.0, 0.0]]]])
+    k = torch.tensor([[[[1.0, 0.0]], [[0.0, 1.0]], [[1.0, 1.0]]]])
+    v = torch.tensor([[[[2.0, 0.0]], [[0.0, 4.0]], [[100.0, 100.0]]]])
+    key_mask = torch.tensor([[[[True, True, False]]]])
+
+    actual = _sdpa_attn_func(q, k, v, attention_mask=key_mask)
+    expected = _sdpa_attn_func(q, k[:, :2], v[:, :2])
+
+    torch.testing.assert_close(actual, expected)
+
+
+def test_sensenova_u1_right_aligns_bnsd_prefix_for_npu_fia():
+    source = torch.tensor(
+        [
+            [[[1], [2], [99], [99], [99]]],
+            [[[3], [4], [5], [6], [7]]],
+        ]
+    )
+    destination = torch.zeros(2, 1, 8, 1, dtype=source.dtype)
+
+    _copy_right_aligned_prefix_bnsd(destination, source, [2, 5])
+
+    assert destination[:, 0, :5, 0].tolist() == [
+        [0, 0, 0, 1, 2],
+        [3, 4, 5, 6, 7],
+    ]
+    assert destination[:, :, 5:].eq(0).all()
+
+
+@pytest.mark.parametrize("available", [False, True])
+def test_sensenova_u1_npu_fia_checks_operator_availability(monkeypatch, available):
+    namespace = SimpleNamespace()
+    if available:
+        namespace.npu_fused_infer_attention_score = object()
+    monkeypatch.setattr(torch.ops, "npu", namespace, raising=False)
+
+    assert npu_fia_available() is available
+
+
+@pytest.mark.parametrize(
+    ("is_npu", "uses_native"),
+    [(False, True), (True, False)],
+)
+def test_sensenova_u1_shared_rmsnorm_dispatch(monkeypatch, is_npu, uses_native):
+    monkeypatch.setattr(current_platform, "is_npu", lambda: is_npu)
+
+    norm = make_qwen3_rms_norm(64, eps=1e-6)
+
+    assert isinstance(norm, RMSNorm)
+    assert norm.cast_x_before_out_mul
+    assert (norm._forward_method == norm.forward_native) is uses_native
+
+
+@torch.no_grad()
+def test_sensenova_u1_fused_dense_mlp_matches_original(monkeypatch):
+    config = SimpleNamespace(
+        hidden_size=16,
+        intermediate_size=24,
+        hidden_act="silu",
+    )
+    with torch.random.fork_rng():
+        torch.manual_seed(37)
+        mlp = Qwen3MLP(config).eval()
+        hidden_states = torch.randn(2, 5, config.hidden_size)
+        expected = mlp(hidden_states)
+
+    monkeypatch.setattr(mlp, "_use_npu_fused_mlp", lambda _x: True)
+    monkeypatch.setattr(
+        torch.ops,
+        "npu",
+        SimpleNamespace(
+            npu_swiglu=lambda x, dim=-1: (
+                F.silu(x.chunk(2, dim=dim)[0]) * x.chunk(2, dim=dim)[1]
+            )
+        ),
+        raising=False,
+    )
+    actual = mlp(hidden_states)
+
+    torch.testing.assert_close(actual, expected)
+    assert set(mlp.state_dict()) == {
+        "gate_proj.weight",
+        "up_proj.weight",
+        "down_proj.weight",
+    }
+    assert (
+        mlp.gate_proj.weight.untyped_storage().data_ptr()
+        == mlp.up_proj.weight.untyped_storage().data_ptr()
+    )
+
+
+def test_sensenova_u1_batched_gqa_matches_unpadded_singletons():
+    generator = torch.Generator().manual_seed(17)
+    q = torch.randn(2, 3, 4, 8, generator=generator)
+    k = torch.randn(2, 8, 2, 8, generator=generator)
+    v = torch.randn(2, 8, 2, 8, generator=generator)
+    valid = torch.ones(2, 8, dtype=torch.bool)
+    valid[0, 2:5] = False
+    attention_mask = valid[:, None, None, :].expand(-1, -1, q.shape[1], -1)
+
+    actual = _sdpa_attn_func(q, k, v, attention_mask=attention_mask)
+
+    for i in range(2):
+        expected = _sdpa_attn_func(
+            q[i : i + 1], k[i : i + 1, valid[i]], v[i : i + 1, valid[i]]
+        )
+        torch.testing.assert_close(actual[i : i + 1], expected)
+
+
+@torch.no_grad()
+def test_sensenova_u1_prefix_and_denoise_attention_match_singletons():
+    config = NEOLLMConfig(
+        hidden_size=64,
+        intermediate_size=128,
+        num_hidden_layers=1,
+        num_attention_heads=4,
+        num_key_value_heads=2,
+        head_dim=16,
+        max_position_embeddings=128,
+    )
+    config._attn_implementation = "eager"
+    with torch.random.fork_rng():
+        torch.manual_seed(23)
+        attention = Qwen3Attention(config, layer_idx=0).eval()
+    generator = torch.Generator().manual_seed(31)
+    text = torch.randn(2, 5, 64, generator=generator)
+    image = torch.randn(2, 3, 64, generator=generator)
+    helper = SimpleNamespace(device=torch.device("cpu"))
+
+    def run(prefix, lengths, image_states):
+        batch_size, width, _ = prefix.shape
+        positions = torch.arange(width).expand(batch_size, -1)
+        indexes = torch.stack(
+            [positions, torch.zeros_like(positions), torch.zeros_like(positions)], dim=1
+        )
+        valid = positions < torch.tensor(lengths)[:, None]
+        cache = DynamicCache(config=config)
+        attention.forward_und(
+            prefix, indexes, create_block_causal_mask(positions, valid), cache
+        )
+        prefix_keys = cache.layers[0].keys.clone()
+        prepare_flash_kv_cache(
+            cache,
+            current_len=3,
+            batch_size=batch_size,
+            prefix_lengths=torch.tensor(lengths),
+        )
+        image_indexes = NEOChatModel._build_t2i_image_indexes(
+            helper, 1, 3, torch.tensor(lengths), torch.device("cpu")
+        )
+        outputs = []
+        for _ in range(2):
+            image_states, _ = attention.forward_gen(
+                image_states,
+                image_indexes,
+                None,
+                cache,
+                update_cache=False,
+            )
+            outputs.append(image_states)
+        torch.testing.assert_close(cache.layers[0].keys, prefix_keys)
+        return prefix_keys, outputs
+
+    keys, batched = run(text, [2, 5], image)
+    for i, length in enumerate([2, 5]):
+        single_keys, single = run(text[i : i + 1, :length], [length], image[i : i + 1])
+        torch.testing.assert_close(keys[i : i + 1, :, :length], single_keys)
+        for step in range(2):
+            torch.testing.assert_close(
+                batched[step][i : i + 1], single[step], atol=1e-5, rtol=1e-4
+            )
+
+
 def test_sensenova_u1_randn_fallback_preserves_device_rng(monkeypatch):
     device_type = current_platform.device_type
     if not device_type or device_type == "cpu":
@@ -341,10 +667,169 @@ def test_sensenova_u1_accepts_openai_image_api_num_frames():
 def test_sensenova_u1_scheduler_capabilities():
     config = SenseNovaU1PipelineConfig()
 
-    assert not config.supports_dynamic_batching()
+    assert config.supports_dynamic_batching()
     assert config.supports_sequential_multi_output_inference()
 
 
+def _make_sensenova_u1_scheduler_request(
+    request_id: str, prompt: str, seed: int | list[int], **sampling_overrides
+) -> Req:
+    sampling = SenseNovaU1SamplingParams(
+        prompt=prompt,
+        seed=seed,
+        **sampling_overrides,
+    )
+    return Req(
+        request_id=request_id,
+        prompt=prompt,
+        seed=seed,
+        sampling_params=sampling,
+        extra=sampling.build_request_extra(),
+    )
+
+
+def test_sensenova_u1_batch_cost_tracks_resolution_steps_and_cfg():
+    config = SenseNovaU1PipelineConfig()
+    batch = SimpleNamespace(
+        width=1024,
+        height=1024,
+        num_inference_steps=5,
+        guidance_scale=4.0,
+        num_outputs_per_prompt=1,
+    )
+
+    assert config.estimate_request_cost(batch) == 32 * 32 * 5 * 2
+
+
+def test_sensenova_u1_multi_output_request_is_not_dynamically_batched():
+    scheduler = object.__new__(Scheduler)
+    scheduler.server_args = SimpleNamespace(pipeline_config=SenseNovaU1PipelineConfig())
+    sampling = SenseNovaU1SamplingParams(
+        prompt="a mountain lake", num_outputs_per_prompt=2
+    )
+    request = SimpleNamespace(
+        is_warmup=False,
+        realtime_session_id=None,
+        session=None,
+        prompt=sampling.prompt,
+        image_path=None,
+        return_file_paths_only=False,
+        num_outputs_per_prompt=2,
+        sampling_params=sampling,
+    )
+
+    assert not scheduler._can_dynamic_batch(request, request)
+    assert (
+        scheduler._get_dynamic_batch_reject_reason(request, request)
+        == "sequential_multi_output"
+    )
+
+
+def test_sensenova_u1_think_mode_request_is_dispatched_without_batching():
+    scheduler = object.__new__(Scheduler)
+    scheduler.server_args = SimpleNamespace(pipeline_config=SenseNovaU1PipelineConfig())
+    scheduler._batch_admission = SimpleNamespace(enabled=True)
+    scheduler._batch_metrics_enabled = False
+    request = _make_sensenova_u1_scheduler_request(
+        "request-0", "a mountain lake", 7, think_mode=True
+    )
+    scheduler.waiting_queue = deque([(b"identity", request, time.monotonic())])
+
+    assert not scheduler._can_dynamic_batch(request, request)
+    assert (
+        scheduler._get_dynamic_batch_reject_reason(request, request)
+        == "pipeline_request_unsupported"
+    )
+    items = scheduler.get_next_batch_to_run()
+    assert items is not None
+    assert items[0][0] == b"identity"
+    assert items[0][1] is request
+    assert not scheduler.waiting_queue
+
+
+@pytest.mark.parametrize(
+    "sampling_overrides",
+    [
+        {"guidance_scale": 1.0},
+        {"num_inference_steps": 25},
+        {"cfg_norm": "global"},
+        {"timestep_shift": 2.0},
+        {"t_eps": 0.01},
+    ],
+)
+def test_sensenova_u1_scheduler_rejects_heterogeneous_generation_options(
+    sampling_overrides,
+):
+    scheduler = object.__new__(Scheduler)
+    scheduler.server_args = SimpleNamespace(pipeline_config=SenseNovaU1PipelineConfig())
+    base = _make_sensenova_u1_scheduler_request("request-0", "first", 7)
+    candidate = _make_sensenova_u1_scheduler_request(
+        "request-1", "second", 19, **sampling_overrides
+    )
+
+    assert not scheduler._can_dynamic_batch(base, candidate)
+
+
+def test_sensenova_u1_scheduler_normalizes_single_output_seed_lists():
+    scheduler = object.__new__(Scheduler)
+    scheduler.server_args = SimpleNamespace(pipeline_config=SenseNovaU1PipelineConfig())
+    requests = [
+        _make_sensenova_u1_scheduler_request("request-0", "first", [7]),
+        _make_sensenova_u1_scheduler_request("request-1", "second", 19),
+    ]
+
+    merged = scheduler._try_merge_generation_reqs(requests)
+
+    assert merged.extra["dynamic_batch_seeds"] == [7, 19]
+
+
+def test_sensenova_u1_scheduler_merge_and_split_preserve_request_order():
+    scheduler = object.__new__(Scheduler)
+    scheduler.server_args = SimpleNamespace(pipeline_config=SenseNovaU1PipelineConfig())
+    requests = [
+        _make_sensenova_u1_scheduler_request(
+            "request-0",
+            "short",
+            7,
+            output_path="/tmp/first",
+            output_file_name="first.png",
+        ),
+        _make_sensenova_u1_scheduler_request(
+            "request-1",
+            "a longer prompt",
+            19,
+            output_path="/tmp/second",
+            output_file_name="second.png",
+        ),
+    ]
+    merged = scheduler._try_merge_generation_reqs(requests)
+    assert merged.prompt == ["short", "a longer prompt"]
+    assert merged.extra["dynamic_batch_seeds"] == [7, 19]
+    expected_paths = [request.output_file_path() for request in requests]
+    assert merged.extra["dynamic_batch_output_paths"] == expected_paths
+    assert requests[0].prompt == "short"
+    outputs = scheduler._split_batched_output(
+        OutputBatch(
+            output=[torch.tensor([7]), torch.tensor([19])],
+            output_file_paths=expected_paths,
+        ),
+        requests,
+    )
+    assert [output.output[0].item() for output in outputs] == [7, 19]
+    assert [output.output_file_paths for output in outputs] == [
+        [path] for path in expected_paths
+    ]
+    assert (
+        scheduler._split_batched_output(
+            OutputBatch(output=[torch.tensor([7])]), requests
+        )
+        is None
+    )
+    requests[1].sampling_params.width = 1024
+    del requests[1]._dynamic_batch_sig
+    assert scheduler._try_merge_generation_reqs(requests) is None
+
+
 def test_sensenova_u1_rejects_multi_gpu_during_arg_validation():
     config = SenseNovaU1PipelineConfig()
 
@@ -626,6 +1111,71 @@ def test_sensenova_u1_generation_stage_uses_sglang_params_and_single_model_batch
     assert model.call_kwargs["seed"] == 123
 
 
+def test_sensenova_u1_generation_stage_passes_dynamic_batch_inputs():
+    sampling = SenseNovaU1SamplingParams(
+        prompt="first prompt",
+        width=1024,
+        height=1024,
+        guidance_scale=4.0,
+        num_inference_steps=5,
+        seed=7,
+    )
+    batch = SimpleNamespace(
+        prompt=["first prompt", "a longer second prompt"],
+        width=sampling.width,
+        height=sampling.height,
+        guidance_scale=sampling.guidance_scale,
+        num_inference_steps=sampling.num_inference_steps,
+        seed=sampling.seed,
+        num_outputs_per_prompt=1,
+        extra={
+            **sampling.build_request_extra(),
+            "dynamic_batch_seeds": [7, 19],
+        },
+        metrics=None,
+    )
+    model = _FakeSenseNovaModel()
+    stage = SenseNovaU1GenerationStage(model=model, tokenizer="tok")
+
+    output = stage.forward(batch, server_args=SimpleNamespace())
+
+    assert len(output.output) == 2
+    assert model.call_kwargs["prompt"] == [
+        "first prompt",
+        "a longer second prompt",
+    ]
+    assert model.call_kwargs["batch_size"] == 2
+    assert model.call_kwargs["seed"] == [7, 19]
+
+
+def test_sensenova_u1_generation_stage_rejects_batched_think_mode():
+    sampling = SenseNovaU1SamplingParams(
+        prompt="first prompt",
+        width=1024,
+        height=1024,
+        think_mode=True,
+    )
+    batch = SimpleNamespace(
+        prompt=["first prompt", "second prompt"],
+        width=sampling.width,
+        height=sampling.height,
+        guidance_scale=sampling.guidance_scale,
+        num_inference_steps=sampling.num_inference_steps,
+        seed=sampling.seed,
+        num_outputs_per_prompt=1,
+        extra={
+            **sampling.build_request_extra(),
+            "dynamic_batch_seeds": [7, 19],
+        },
+        metrics=None,
+    )
+
+    with pytest.raises(ValueError, match="think_mode"):
+        SenseNovaU1GenerationStage(
+            model=_FakeSenseNovaModel(), tokenizer="tok"
+        ).forward(batch, server_args=SimpleNamespace())
+
+
 def test_sensenova_u1_multi_output_request_expands_before_generation_stage():
     sampling = SenseNovaU1SamplingParams(
         prompt="a mountain lake",