fix: GdnCuTileEngine import path in cutile conftest and _pygraph error msg

[vedaanta]

Problem

test/python/linear_attention/cutile/conftest.py imports GdnCuTileEngine and KdaCuTileEngine from cudnn.engines:

from cudnn.engines import GdnCuTileEngine, KdaCuTileEngine

However these classes are only exported from cudnn.linear_attention.cutile. The cudnn.engines.__getattr__ only resolves factory names registered in its own MANIFEST (e.g. GdnEngines), not individual engine classes that live in sub-packages.

This caused all 1730 tests in test/python/linear_attention/cutile/ to fail at setup with ImportError in every nightly CI run.

python/cudnn/_pygraph.py had the same wrong path in its user-facing error message.

Fix

• conftest.py: from cudnn.linear_attention.cutile import GdnCuTileEngine, KdaCuTileEngine
• _pygraph.py: update example path in error message to match

Labels

cat-bugfix, mod-linear-attention, orig-internal

Summary by CodeRabbit

• Bug Fixes
  • Updated GDN backend error messaging to reference the correct linear-attention cuTile engine location.
  • Updated cuTile and FROST test coverage to use the current linear-attention engine locations, improving validation of GDN and KDA workflows.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Path: .coderabbit.yaml

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Plan: Enterprise

Run ID: 5379d9b7-0216-4f3f-8bd7-5b8ba53a5943

📥 Commits

Reviewing files that changed from the base of the PR and between cabb38a and ec907d1.

📒 Files selected for processing (3)

• test/python/linear_attention/frost/test_gdn2_prefill_kernel.py
• test/python/linear_attention/frost/test_gdn_bprop_kernel.py
• test/python/linear_attention/frost/test_kda_prefill_kernel.py

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📝 Walkthrough

Walkthrough

The PR updates the GDN backend error and linear attention test imports to use the current cuTile and FROST engine modules.

Changes

Linear attention engine references

Layer / File(s)	Summary
Align engine module references python/cudnn/_pygraph.py, test/python/linear_attention/cutile/conftest.py	The backend error and cuTile fixture now reference engines from cudnn.linear_attention.cutile.
Add FROST engine imports test/python/linear_attention/frost/*	FROST tests import Gdn2FrostEngine, GdnFrostEngine, and KdaFrostEngine from cudnn.linear_attention.frost.

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

Possibly related PRs

• NVIDIA/cudnn-frontend#502 — Updates imports and error messages for relocated linear attention engine classes.
• NVIDIA/cudnn-frontend#503 — Updates GDN and FROST engine APIs in cudnn.linear_attention.

Suggested labels: mod-frontend, cat-cleanup, mod-frost

Suggested reviewers: yangxu1990uiuc

🚥 Pre-merge checks | ✅ 3 | ❌ 2

❌ Failed checks (2 warnings)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description explains the problem and fix, but it omits the required checklist, affected area, related issues, API impact, and exact testing results.	Complete the template sections and include exact test commands with results, or explain why testing was not run.
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the corrected GdnCuTileEngine import path and the related _pygraph error-message update.
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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[vedaanta]

@cudnn-ci-bot run frost

[cudnn-ci-bot]

🚀 Running mirror pipeline

Branch: cudnn-gh/pr-513-cabb38a
Pipeline: 61624399
Targets: frost

[vedaanta]

@cudnn-ci-bot run frost

[cudnn-ci-bot]

🚀 Running mirror pipeline

Branch: cudnn-gh/pr-513-ec907d1
Pipeline: 61650316
Targets: frost