[Bugfix] Adding Rope Scaling to Handle Both rope_type and type in vLLM Neuron Code

[vara-bonthu]

PR Description

This PR addresses a bug in the vLLM Neuron code related to handling different rope scaling configurations. Previously, the code only supported handling rope_scaling["type"], which led to errors when encountering rope_scaling["rope_type"] or unsupported scaling types like linear.

The changes in this PR introduce support for both rope_type and type within the model configuration to ensure compatibility with models using different rope scaling strategies. The updated logic also ensures backward compatibility with legacy models that use the su type and proper error handling for unsupported types.

Changes Summary:

Files Modified: vllm/config.py

Key Changes:

• Introduced logic to handle both rope_type and type keys from the hf_config.
• Added error handling to raise appropriate exceptions if neither type nor rope_type is present.
• Kept backward compatibility for the su rope scaling type and handled the newly supported llama3 and longrope types.
• Fixed the issue where the linear scaling type would raise a ValueError.

Example of the issue before the fix:

I was encountering the following error during model initialization in the vLLM Neuron code:

Unrecognized keys in `rope_scaling` for 'rope_type'='linear': {'type'}

FIX #xxxx (link existing issues this PR will resolve)

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PR Checklist (Click to Expand)

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[jimburtoft]

This worked for me!