[None][fix] Restore CpType import for HELIX KV cache

[chzblych]

Description

#18025 removed the CpType import while deleting star-attention support, but tensorrt_llm/_torch/pyexecutor/_util.py still uses CpType.HELIX in the HELIX KV-cache estimation and capacity paths. This leaves those references undefined and causes the baseline-gated legacy lint check to fail.

Restore the shared CpType import. This is an internal one-line fix with no API or runtime behavior change beyond making the existing HELIX paths valid again.

Test Coverage

• python3 scripts/legacy_utils.py lint-precommit tensorrt_llm/_torch/pyexecutor/_util.py
• ruff check --config ruff-legacy.toml --select F821 tensorrt_llm/_torch/pyexecutor/_util.py
• git diff --check

PR Checklist

• PR description clearly explains what and why.

• PR follows the TRT-LLM coding guidelines.

• No API changes, new dependencies, ownership changes, documentation changes, or architecture changes.

• The targeted CI-equivalent lint checks pass.

• Please check this after reviewing the above items as appropriate for this PR.

Dev Engineer Review

• Restores the CpType import in tensorrt_llm/_torch/pyexecutor/_util.py.
• Fixes undefined CpType.HELIX references in HELIX KV-cache estimation and capacity paths.
• Preserves API and runtime behavior.
• No configuration, public entity, or test-list changes.
• Targeted lint and whitespace checks pass.

QA Engineer Review

No test changes.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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📥 Commits

Reviewing files that changed from the base of the PR and between 958d651 and 136872e.

📒 Files selected for processing (1)

• tensorrt_llm/_torch/pyexecutor/_util.py

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Walkthrough

The utility module now imports CpType alongside Mapping.

Changes

Context-parallel import

Layer / File(s)	Summary
Utility mapping import tensorrt_llm/_torch/pyexecutor/_util.py	The mapping import includes CpType alongside Mapping.

Estimated code review effort: 1 (Trivial) | ~2 minutes

Merge Risk: ⚪ Minimal · up to 13687

This localized fix restores the import required by existing HELIX KV-cache paths without changing product behavior or public interfaces. No actionable merge-blocking risk remains beyond normal checks and review.

Suggested reviewers: bowenfu

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description check	✅ Passed	The description explains the issue, solution, test coverage, and checklist items clearly and completely.
Title check	✅ Passed	The title clearly and concisely describes restoring the CpType import for HELIX KV-cache handling.
Docstring Coverage	✅ Passed	Docstring check was indeterminate for this PR — some files could not be analyzed in time. Not blocking.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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[chzblych]

/bot skip --comment "Hotfix for release check"

[tensorrt-cicd]

PR_Github #68830 [ skip ] triggered by Bot. Commit: 136872e Link to invocation

[tensorrt-cicd]

PR_Github #68830 [ skip ] completed with state SUCCESS. Commit: 136872e
Skipping testing for commit 136872e

Link to invocation

[lori-ren]

Sorry for the inconvenience @chzblych. When drafting the PR, in PR's baseline codebase CpType has only one usage which serves for star attention and it is safe to delete the import. However, #17866 was merged yesterday, which adds a new reference to CpType. Since it appears in a totally different line, git fast-forward did not detect it as a conflict and post-merge breaks unexpectedly.