[1/N][Attention] Restructure attention: move files

[MatthewBonanni]

Purpose

Implement step 1 of #31919. This PR consists solely of file renaming and movement, and the necessary updates to imports.

• Move vllm/attention/layers to vllm/model_executor/layers/attention
• Move vllm/attention/backends/abstract.py to vllm/v1/attention/backend.py
• Move vllm/attention/backends/registry.py to vllm/v1/attention/backends/registry.py
• Eliminate vllm/attention/backends folder
• Move vllm/attention/utils/fa_utils.py to vllm/v1/attention/backends/fa_utils.py
• Move vllm/attention/ops to vllm/v1/attention/ops
• Move vllm/attention/selector.py to vllm/v1/attention/selector.py

Note

• vllm/v1/attention is subject to more mypy scrutiny than vllm/attention since fixed mypy warnings for files vllm/v1/attention with TEMPORARY workaround #31465
• Since this PR moves files from vllm/attention to vllm/v1/attention, new pre-commit issues arise
• Due to its size, we want to keep this PR as simple as possible: only file renaming and path changes
• Therefore, we have added vllm/v1/attention/backends/fa_utils.py to EXCLUDES
• This will be addressed in the next PR

Test Plan

CI

Test Result

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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.
• (Optional) Release notes update. If your change is user facing, please update the release notes draft in the Google Doc.

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Note

Bulk path migration with no intended functional changes.

• Move vllm/attention/backends/abstract.py to vllm/v1/attention/backend.py, and backends/registry.py + utils/fa_utils.py to vllm/v1/attention/backends/
• Move attention ops from vllm/attention/ops to vllm/v1/attention/ops and selector to vllm/v1/attention/selector.py
• Relocate attention layers to vllm/model_executor/layers/attention/
• Update all imports across models, tests, examples, benchmarks, and engine/platform code to new v1 paths
• CI: adjust Buildkite watched paths, add ROCm file matchers for new paths, and update tests to use v1 modules
• Repo metadata: update CODEOWNERS and Mergify label rules to point at v1 attention paths
• Tooling: update pre-commit/mypy EXCLUDE to vllm/v1/attention/ops and backends/fa_utils.py
• Docs: fix references to new v1 attention locations

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Note

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Note

Migrates attention code into the vllm/v1 namespace and updates references across the repo.

• Move vllm/attention/backends/abstract.py → vllm/v1/attention/backend.py; backends/registry.py and utils/fa_utils.py → vllm/v1/attention/backends/
• Move ops vllm/attention/ops → vllm/v1/attention/ops, selector → vllm/v1/attention/selector.py, and attention layers → vllm/model_executor/layers/attention/
• Update imports across models, tests, examples, benchmarks, and engine/platform code to new v1 paths
• CI: adjust Buildkite watched paths, add ROCm file matchers for new v1 locations; tests updated accordingly
• Repo metadata: update CODEOWNERS and Mergify label rules to point at v1 attention paths
• Tooling: update pre-commit/mypy EXCLUDE for vllm/v1/attention/ops and backends/fa_utils.py
• Docs: fix references to new v1 attention modules

^{Written by Cursor Bugbot for commit d1dee22. This will update automatically on new commits. Configure here.}

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Note

^{Cursor Bugbot is generating a summary for commit 7613b31. Configure here.}

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Note

Bulk path migration of attention code to the v1 namespace; no functional changes intended.

• Move vllm/attention/backends/abstract.py → vllm/v1/attention/backend.py, registry and fa_utils.py → vllm/v1/attention/backends/
• Move ops vllm/attention/ops → vllm/v1/attention/ops, selector → vllm/v1/attention/selector.py
• Relocate attention layers to vllm/model_executor/layers/attention/
• Update imports across models, tests, examples, benchmarks, engine, and platforms to new v1 paths
• CI: adjust Buildkite watched paths, add ROCm matchers for vllm/v1/attention/**, update tests to new modules
• Repo metadata: update CODEOWNERS and Mergify label rules to point at v1 attention paths
• Tooling: update pre-commit/mypy EXCLUDE for vllm/v1/attention/ops and backends/fa_utils.py
• Docs: fix references to new v1 attention locations

^{Written by Cursor Bugbot for commit 7613b31. This will update automatically on new commits. Configure here.}

[gemini-code-assist]

Code Review

The pull request involves extensive changes and refactoring within the vllm project's attention mechanisms, specifically impacting model_executor/layers/attention and introducing a new v1/attention module. These changes appear to touch various attention implementations such as chunked_local_attention, cross_attention, encoder_only_attention, static_sink_attention, and different operational backends like flashmla, paged_attn, and Triton-based prefill and decode attentions. No specific code changes or review comments were provided to detail the nature or purpose of these modifications.

[mergify]

Documentation preview: https://vllm--31916.org.readthedocs.build/en/31916/

[ProExpertProg]

Confirming there should be no changes other than imports and renames!

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @MatthewBonanni.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @MatthewBonanni.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork