refactor: remove MetaInfoHash class

[yzh119]

📌 Description

This class is not required after @jimmyzho 's refactor work in https://github.com/flashinfer-ai/flashinfer/pull/1967/files, and the only remaining pieces requiring its value is deepgemm (because of different artifact structure, deepgemm only have a kernel_map.json instead of header file).

In this PR we remove the class MetaInfoHash to stop people further updating its content, and move the special case kernel map hash to deepgemm.py .

🔍 Related Issues

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Reviewer Notes

cc @jimmyzho @cyx-6

Summary by CodeRabbit

• Refactor
  • Kernel metadata handling simplified so kernel map objects initialize without external hash input
  • Kernel validation standardized to use a fixed internal hash constant
  • Removed an obsolete public checksum data structure from the public surface
  • Public API trimmed and clarified for a leaner interface

[gemini-code-assist]

Summary of Changes

Hello @yzh119, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request refactors the artifact hash management by eliminating the MetaInfoHash class. This change streamlines the codebase by removing an unused abstraction and directly integrating the deepgemm kernel map hash into its specific usage context. The primary goal is to prevent future misuse or unnecessary updates to a deprecated class, ensuring a cleaner and more maintainable structure for artifact checksums.

Highlights

• Removal of MetaInfoHash Class: The MetaInfoHash class, previously used for storing various metadata hashes, has been entirely removed from flashinfer/artifacts.py as it was no longer required after a previous refactor.
• Relocation of DeepGemm Kernel Map Hash: The DEEPGEMM hash, which was the only remaining dependency on MetaInfoHash, has been moved directly into the KernelMap class within flashinfer/deep_gemm.py as a static attribute KERNEL_MAP_HASH.
• Simplified KernelMap Initialization: The KernelMap class constructor no longer requires a sha256 argument, as the necessary hash is now internally defined within the class itself.

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[gemini-code-assist]

Code Review

This pull request is a good refactoring that removes the unused MetaInfoHash class. The relevant hash constant is moved into the KernelMap class within deep_gemm.py, which is the only place it's used. This improves code organization by increasing locality and removing dead code. The changes are straightforward and correctly implemented. I have one minor suggestion to improve naming for better clarity.

[gemini-code-assist]

For better readability and consistency with the filename kernel_map.json, consider renaming the instance variable indice to kernel_map. This would make it clearer what this variable holds. This change would need to be applied to all usages of self.indice within the KernelMap class.

Suggested change

	self.indice = None
	self.kernel_map = None

[coderabbitai]

Note

Other AI code review bot(s) detected

CodeRabbit has detected other AI code review bot(s) in this pull request and will avoid duplicating their findings in the review comments. This may lead to a less comprehensive review.

Walkthrough

The PR removes the MetaInfoHash dataclass from flashinfer/artifacts.py and updates flashinfer/deep_gemm.py so KernelMap uses a fixed KERNEL_MAP_HASH class constant and no longer requires a sha256 constructor argument.

Changes

Cohort / File(s)	Summary
Artifacts dataclass removal flashinfer/artifacts.py	Deleted the public frozen dataclass MetaInfoHash (fields: DEEPGEMM, TRTLLM_GEN_FMHA, TRTLLM_GEN_BMM, TRTLLM_GEN_GEMM). Added a comment near ArtifactPath noting DEEPGEMM kernel map hash location.
KernelMap hash and API change flashinfer/deep_gemm.py	Introduced KERNEL_MAP_HASH class constant; removed sha256 constructor param from KernelMap and changed global instantiation to KernelMap(). Replaced uses of self.sha256 with self.KERNEL_MAP_HASH. Adjusted import to drop MetaInfoHash.

Sequence Diagram(s)

sequenceDiagram
    autonumber
    participant Caller as deep_gemm user code
    participant KernelMap_old as KernelMap (old)
    participant Filesystem as kernel_map.json

    Note over KernelMap_old: OLD FLOW (before PR)
    Caller->>KernelMap_old: KernelMap(sha256=MetaInfoHash.DEEPGEMM)
    KernelMap_old->>Filesystem: open(kernel_map.json)
    Filesystem-->>KernelMap_old: json data
    KernelMap_old->>Filesystem: get_cubin(indice_path, sha256)
    Filesystem-->>Caller: validation result

Loading

sequenceDiagram
    autonumber
    participant Caller as deep_gemm user code
    participant KernelMap_new as KernelMap (new)
    participant Filesystem as kernel_map.json

    Note over KernelMap_new: NEW FLOW (this PR)
    Caller->>KernelMap_new: KernelMap()
    KernelMap_new->>Filesystem: open(kernel_map.json)
    Filesystem-->>KernelMap_new: json data
    KernelMap_new->>Filesystem: get_cubin(indice_path, KERNEL_MAP_HASH)
    Filesystem-->>Caller: validation result

Loading

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

• Verify KERNEL_MAP_HASH equals the previous MetaInfoHash.DEEPGEMM value.
• Search the codebase for remaining MetaInfoHash imports/usages.
• Confirm no callers still pass a sha256 to KernelMap and that tests (if any) reflect the API change.

Possibly related PRs

• misc: Update artifacts docstring and MetaInfoHash #1967 — Similar removal/replace of MetaInfoHash usage with alternate checksum handling.
• unittest: fix deepgemm sha256 #1953 — Updates the DEEPGEMM hash value that corresponds to the KERNEL_MAP_HASH embedded here.

Suggested reviewers

• cyx-6
• yongwww
• wenscarl
• nvmbreughe

Poem

🐇 I hid the dataclass, tucked the hash in place,
A constant now guides the kernel-map race.
No args to pass, no fields to prune,
Quiet refactor under the moon. ✨

Pre-merge checks and finishing touches

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately and concisely describes the main refactoring change: removing the MetaInfoHash class from the codebase.
Description check	✅ Passed	The PR description covers the key sections: explains why the change is needed (referencing prior refactor PR #1967), describes what is being removed and moved, and includes checklist items marked as complete with reviewer mentions.

✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

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📜 Recent review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between b75d4fa and f6d4bc4.

📒 Files selected for processing (1)

• flashinfer/artifacts.py (1 hunks)

⏰ Context from checks skipped due to timeout of 90000ms. You can increase the timeout in your CodeRabbit configuration to a maximum of 15 minutes (900000ms). (1)

• GitHub Check: Deploy Docs

🔇 Additional comments (2)

flashinfer/artifacts.py (2)

98-99: LGTM! Comment addresses past review feedback.

The comment appropriately documents the cross-file dependency between ArtifactPath.DEEPGEMM and KernelMap.KERNEL_MAP_HASH in flashinfer/deep_gemm.py, helping maintainers keep these values synchronized. This directly addresses jimmyzho's earlier suggestion.

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17-100: MetaInfoHash removal verified—no remaining references found.

Comprehensive searches across the entire codebase confirm complete removal with no imports, usages, or exports remaining. The change is safe.

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