[BugFix] Async scheduling and PP compatibility with DP

[jesse996]

What this PR does / why we need it?

based on the vllm-project/vllm#23770,
fix Async scheduling and PP compatibility with DP, also fixes issue with finished requests not being processed in async scheduling and PP cases, and possible worker race conditions.

Does this PR introduce any user-facing change?

How was this patch tested?

• vLLM version: v0.10.2
• vLLM main: vllm-project/vllm@544fe76

[github-actions]

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[gemini-code-assist]

Code Review

This pull request aims to fix issues related to asynchronous scheduling and pipeline parallelism (PP) compatibility with data parallelism (DP). The changes in vllm_ascend/worker/worker_v1.py introduce a check to prevent deadlocks when no tokens are scheduled and refactor the model execution logic for intermediate pipeline ranks. While the refactoring improves clarity, it introduces a critical type error where a function returns a value that violates its type hint, potentially causing runtime failures. My review focuses on correcting this type violation to ensure the fix is robust.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 75.25%. Comparing base (1bbb20e) to head (eada40c).
⚠️ Report is 26 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2796      +/-   ##
==========================================
+ Coverage   74.76%   75.25%   +0.48%     
==========================================
  Files         150      154       +4     
  Lines       20891    21413     +522     
==========================================
+ Hits        15620    16115     +495     
- Misses       5271     5298      +27     

Flag	Coverage Δ
unittests	75.25% <100.00%> (+0.48%)	⬆️

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[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.

[github-actions]

This pull request has conflicts, please resolve those before we can evaluate the pull request.