[diffusion] refactor: move model_stages into stages folder

[mickqian]

Motivation

Modifications

Accuracy Tests

Benchmarking and Profiling

Checklist

• Format your code according to the Format code with pre-commit.
• Add unit tests according to the Run and add unit tests.
• Update documentation according to Write documentations.
• Provide accuracy and speed benchmark results according to Test the accuracy and Benchmark the speed.
• Follow the SGLang code style guidance.

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[mickqian]

/tag-and-rerun-ci

[gemini-code-assist]

Summary of Changes

Hello @mickqian, 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 focuses on a structural refactoring, reorganizing model-specific stage definitions within the project. The primary goal is to enhance code organization and maintainability by consolidating pipeline-related components into a more intuitive directory structure, making it easier for developers to navigate and understand the codebase.

Highlights

• Refactor Model Stages: Model-specific stage definitions have been relocated from sglang.multimodal_gen.runtime.models.model_stages to a new, more logical directory: sglang.multimodal_gen.runtime.pipelines_core.stages.model_specific_stages.
• Updated Import Paths: All affected files, including glm_image.py, mova_pipeline.py, and qwen_image.py, have had their import statements updated to reflect the new locations of the moved stage modules.

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Changelog

• python/sglang/multimodal_gen/runtime/models/model_stages/glm_image.py
  • Renamed to python/sglang/multimodal_gen/runtime/pipelines_core/stages/model_specific_stages/glm_image.py.
• python/sglang/multimodal_gen/runtime/models/model_stages/mova.py
  • Renamed to python/sglang/multimodal_gen/runtime/pipelines_core/stages/model_specific_stages/mova.py.
• python/sglang/multimodal_gen/runtime/models/model_stages/qwen_image_layered.py
  • Renamed to python/sglang/multimodal_gen/runtime/pipelines_core/stages/model_specific_stages/qwen_image_layered.py.
• python/sglang/multimodal_gen/runtime/pipelines/glm_image.py
  • Updated the import path for GlmImageBeforeDenoisingStage to its new location within pipelines_core/stages/model_specific_stages.
• python/sglang/multimodal_gen/runtime/pipelines/mova_pipeline.py
  • Updated import paths for MOVADecodingStage, MOVADenoisingStage, MOVALatentPreparationStage, and MOVATimestepPreparationStage to their new pipelines_core/stages/model_specific_stages location.
• python/sglang/multimodal_gen/runtime/pipelines/qwen_image.py
  • Updated the import path for QwenImageLayeredBeforeDenoisingStage to its new location under pipelines_core/stages/model_specific_stages.

Activity

• The pull request was opened by mickqian.
• No human activity (comments, reviews, etc.) has been recorded on this pull request yet.

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[gemini-code-assist]

Code Review

This pull request refactors the project structure by moving model-specific pipeline stages from runtime/models/model_stages to a more appropriate location at runtime/pipelines_core/stages/model_specific_stages. This change improves the organization of the codebase by grouping pipeline stages together, making the project structure more logical and easier to navigate. The import paths have been updated accordingly across the affected pipeline files. The changes are clean, focused, and represent a good improvement to the project's maintainability. I have reviewed the changes and found no issues.