fix(native): remove deadlock detection

[kixelated]

Summary

• remove the debug-only deadlock checker and its process-lifetime thread
• replace the remaining low-frequency parking_lot::Mutex with std::sync::Mutex, removing moq-native’s direct parking_lot dependency
• stop enabling parking_lot/deadlock_detection across release builds; Cargo feature unification compiled its per-lock tracking even though #[cfg(debug_assertions)] prevented the checker from running

Fixes #3125.

Public API changes

None.

Test plan

• nix develop --command just fix
• nix develop --command just check
• nix develop --command just test (3264 passed, 1 skipped)
• inspected cargo tree --locked -p moq-relay -e features -i parking_lot_core to confirm only parking_lot_core/default remains enabled

Cross-package sync is not applicable because this changes neither a public API nor a wire format.

(Written by Codex)

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-08-29T04:32:43.081704Z	a595872	PR opened

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[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: a595872233

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[chatgpt-codex-connector]

Add a regression check for the disabled feature

This bug fix has no automated check that parking_lot/deadlock_detection remains absent from the unified release feature graph. A later dependency change can silently re-enable the per-lock tracking that this commit removes while all behavioral tests still pass, so encode the inspected cargo tree invariant in a regression check that fails when the feature returns. (Written by GPT-5.6 Sol)

AGENTS.md reference: AGENTS.md:L141-L141

Useful? React with 👍 / 👎.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: da4ab485-0326-4bb3-9880-1f3834ecf05a

📥 Commits

Reviewing files that changed from the base of the PR and between 85c9f48 and a595872.

⛔ Files ignored due to path filters (1)

• Cargo.lock is excluded by !**/*.lock

📒 Files selected for processing (3)

• rs/moq-native/Cargo.toml
• rs/moq-native/src/accept.rs
• rs/moq-native/src/log.rs

💤 Files with no reviewable changes (2)

• rs/moq-native/src/log.rs
• rs/moq-native/Cargo.toml

Included review availability: Your plan provides up to 4 included reviews per hour; 2 remain after this review.

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Walkthrough

The native module removes the parking_lot dependency and its deadlock detection feature. The accept health state changes to std::sync::Mutex, with lock results unwrapped at each access. The logging initialization no longer starts the debug-only deadlock detector, and the detector implementation is removed.

Merge Risk: 🔵 Low · up to a5958

The change removes deadlock-detection overhead and switches native health-state locking to the standard library without changing public APIs or wire formats. It is mergeable with owner awareness because a panic while holding the health-state lock could poison it and cause later lock attempts to panic.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 inconclusive)

Check name	Status	Explanation	Resolution
Linked Issues check	❓ Inconclusive	The reviewable changes satisfy the code-related objectives in issue #3125 by removing deadlock detection and the direct parking_lot dependency. Cargo.lock regeneration and removal of the backtrace dep…	Review Cargo.lock outside the filtered file set. Confirm it was regenerated and that the parking_lot deadlock_detection and backtrace dependency edges are removed as required by issue #3125.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly summarizes the primary change: removing native deadlock detection.
Description check	✅ Passed	The description directly explains the deadlock checker removal, mutex replacement, dependency change, testing, and linked issue.
Out of Scope Changes check	✅ Passed	All reviewed changes support the linked issue. The mutex replacement removes the remaining dependency usage, and the log changes remove the unused deadlock checker and its thread.
Docstring Coverage	✅ Passed	Docstring coverage is 80.00% which is sufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 5 functions across 1 files.

Full details: Linked Issues check

Explanation

The reviewable changes satisfy the code-related objectives in issue #3125 by removing deadlock detection and the direct parking_lot dependency. Cargo.lock regeneration and removal of the backtrace dependency edge cannot be verified because Cargo.lock is excluded by the !**/*.lock path filter.

• Fix all pre-merge checks with AI

✨ Finishing Touches

✨ Simplify code

• Create PR with simplified code
• Commit simplified code in branch codex/remove-deadlock-detection

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