[Misc] Minor enhancement of benchmark_moe

[jeejeelee]

Essential Elements of an Effective PR Description Checklist

• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
• The test plan, such as providing test command.
• The test results, such as pasting the results comparison before and after, or e2e results
• (Optional) The necessary documentation update, such as updating supported_models.md and examples for a new model.

Purpose

The current code doesn't check whether intermediate_size can be evenly divided by TP, which may lead to generating some useless configs. This PR mainly ensures that intermediate_size can be divided by TP.

Test Plan

Test Result

(Optional) Documentation Update

[gemini-code-assist]

Code Review

This pull request adds a check to ensure intermediate_size is divisible by the tensor parallelism size in the MoE benchmark, which is a good correctness fix. My review focuses on improving the implementation of this check. I've suggested inlining the assertion, which simplifies the code and removes a new helper function that has a misleading generic name for a specific purpose.

[gemini-code-assist]

Since this function is only used once, it can be inlined at the call site for simplicity. This also avoids introducing a new helper function with a generic name but a specific implementation, which could be misleading for future maintenance.

[gemini-code-assist]

Inlining the divisibility check here makes the code more direct and removes the need for a separate helper function.

Suggested change

	ensure_divisibility(intermediate_size, args.tp_size)
	assert intermediate_size % args.tp_size == 0, f"intermediate_size {intermediate_size} is not divisible by tp {args.tp_size}"

[github-actions]

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