### What this PR does / why we need it?
This PR optimizes the Qwen3.5 and Qwen3Next GDN prefill path on Ascend
by reducing host/device synchronization overhead.
The current implementation of the `chunk_gated_delta_rule` path for
variable-length sequences prepares chunk metadata during the forward
pass. This approach triggers frequent CPU intervention and host/device
round-trips. When running prefill-heavy workloads with asynchronous
scheduling enabled, these synchronizations result in execution "bubbles"
and prefill stalling (stuttering). **Note that this does not cause
asynchronous scheduling to fail; rather, it prevents the system from
reaching its theoretical throughput due to these unnecessary stalls.**
To resolve this, the patch moves metadata preparation out of the hot
path:
- **Prebuilt Metadata:** All non-speculative varlen chunk metadata for
GDN is now prebuilt on the CPU.
- **Asynchronous Transfer:** Staging buffers are kept in pinned memory
and transferred to the NPU asynchronously.
- **Integration:** The prebuilt bundle is attached to GDN attention
metadata via `patch_gdn_attn.py` and passed into Triton wrappers.
- **Backward Compatibility:** Triton wrappers fall back to the legacy
preparation path if no prebuilt metadata is provided.
- vLLM version: v0.17.0
- vLLM main:
8b6325758c
---------
Signed-off-by: maoxx241 <maomaoyu870@gmail.com>
### What this PR does / why we need it?
This pull request refactors the dispatch mechanism for the
**triton-ascend-specific operators** `insert_slice`, `extract_slice`,
and `get_element` to ensure compatibility with both CANN 8.5 and 9.0.
A unified helper function, `_resolve_triton_ascend_op`, has been
introduced in `vllm_ascend/ops/triton/triton_utils.py`. This function
dynamically resolves these operators by first attempting to import them
from the `triton.language.extra.cann.extension` module, which is present
in newer CANN versions. If that fails, it falls back to the standard
`triton.language` module.
This approach centralizes operator dispatch logic, allowing individual
Triton kernels to use these functions without being aware of the
underlying Triton/CANN version. All call sites have been updated to use
these new unified functions.
### Does this PR introduce _any_ user-facing change?
No. This is an internal refactoring of operator implementations and does
not introduce any user-facing changes.
### How was this patch tested?
CI is expected to pass with existing tests.
**Testing Context:**
- vLLM version: v0.16.0
- vLLM main: `15d76f74e2fdb12a95ea00f0ca283acf6219a2b7`
Signed-off-by: linfeng-yuan <1102311262@qq.com>
### What this PR does / why we need it?
qwen3-next suppot triton chunk_gated_delta_rule ops
### co-owners
@OsirisDuan
- vLLM version: v0.11.2
Signed-off-by: shiyuan680 <917935075@qq.com>
