ci/cd: bring up flashinfer-cubin package (#1718)

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## 📌 Description

User prefers a standalone wheel for cubin files in flashinfer, this PR
implements this feature.

## 🔍 Related Issues

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## 🚀 Pull Request Checklist

Thank you for contributing to FlashInfer! Before we review your pull
request, please make sure the following items are complete.

### ✅ Pre-commit Checks

- [ ] I have installed `pre-commit` by running `pip install pre-commit`
(or used your preferred method).
- [ ] I have installed the hooks with `pre-commit install`.
- [ ] I have run the hooks manually with `pre-commit run --all-files`
and fixed any reported issues.

> If you are unsure about how to set up `pre-commit`, see [the
pre-commit documentation](https://pre-commit.com/).

## 🧪 Tests

- [ ] Tests have been added or updated as needed.
- [ ] All tests are passing (`unittest`, etc.).

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Author: yzh119

.pre-commit-config.yaml

@@ -47,6 +47,9 @@ repos:
       rev: 'v1.17.1'  # Use the sha / tag you want to point at
       hooks:
       -   id: mypy
+          args: ["--config-file", "pyproject.toml", "--exclude", "flashinfer-cubin/"]
+          files: ^flashinfer/
+          exclude: ^(flashinfer-cubin/|3rdparty/|build/)
 
   - repo: https://github.com/astral-sh/ruff-pre-commit
     # Ruff version.

flashinfer-cubin/.gitignore

@@ -0,0 +1,2 @@
+build/
+flashinfer_cubin/cubins/

flashinfer-cubin/MANIFEST.in

@@ -0,0 +1,3 @@
+include README.md
+include LICENSE
+recursive-include flashinfer_cubin/cubins *

flashinfer-cubin/build_wheel.py

@@ -0,0 +1,66 @@
+#!/usr/bin/env python3
+"""
+Copyright (c) 2025 by FlashInfer team.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+"""
+
+import os
+import subprocess
+import sys
+from pathlib import Path
+
+
+def build_wheel():
+    """Build the flashinfer-cubin wheel."""
+
+    # Change to the flashinfer-cubin directory
+    script_dir = Path(__file__).parent
+    os.chdir(script_dir)
+
+    print("Building flashinfer-cubin wheel...")
+    print(f"Working directory: {script_dir}")
+
+    # Clean previous builds
+    dist_dir = script_dir / "dist"
+    build_dir = script_dir / "build"
+    egg_info_dir = script_dir / "flashinfer_cubin.egg-info"
+
+    for dir_to_clean in [dist_dir, build_dir, egg_info_dir]:
+        if dir_to_clean.exists():
+            print(f"Cleaning {dir_to_clean}")
+            import shutil
+
+            shutil.rmtree(dir_to_clean)
+
+    # Build wheel
+    try:
+        subprocess.run([sys.executable, "setup.py", "bdist_wheel"], check=True)
+
+        print("Wheel built successfully!")
+
+        # List built wheels
+        if dist_dir.exists():
+            wheels = list(dist_dir.glob("*.whl"))
+            if wheels:
+                print(f"Built wheel: {wheels[0]}")
+            else:
+                print("No wheel files found in dist/")
+
+    except subprocess.CalledProcessError as e:
+        print(f"Failed to build wheel: {e}")
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    build_wheel()

flashinfer-cubin/download_cubins.py

@@ -0,0 +1,80 @@
+#!/usr/bin/env python3
+"""
+Copyright (c) 2025 by FlashInfer team.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+"""
+
+import os
+import sys
+import argparse
+from pathlib import Path
+
+# Add parent directory to path to import flashinfer modules
+sys.path.insert(0, str(Path(__file__).parent.parent))
+
+from flashinfer.artifacts import download_artifacts
+from flashinfer.jit.cubin_loader import FLASHINFER_CUBINS_REPOSITORY
+
+
+def main():
+    parser = argparse.ArgumentParser(
+        description="Download FlashInfer cubins from artifactory"
+    )
+    parser.add_argument(
+        "--output-dir",
+        "-o",
+        type=str,
+        default="flashinfer_cubin/cubins",
+        help="Output directory for cubins (default: flashinfer_cubin/cubins)",
+    )
+    parser.add_argument(
+        "--threads",
+        "-t",
+        type=int,
+        default=4,
+        help="Number of download threads (default: 4)",
+    )
+    parser.add_argument(
+        "--repository",
+        "-r",
+        type=str,
+        default=None,
+        help="Override the cubins repository URL",
+    )
+
+    args = parser.parse_args()
+
+    # Set environment variables to control download behavior
+    if args.repository:
+        os.environ["FLASHINFER_CUBINS_REPOSITORY"] = args.repository
+
+    os.environ["FLASHINFER_CUBIN_DIR"] = str(Path(args.output_dir).absolute())
+    os.environ["FLASHINFER_CUBIN_DOWNLOAD_THREADS"] = str(args.threads)
+
+    print(f"Downloading cubins to {args.output_dir}")
+    print(
+        f"Repository: {os.environ.get('FLASHINFER_CUBINS_REPOSITORY', FLASHINFER_CUBINS_REPOSITORY)}"
+    )
+
+    # Use the existing download_artifacts function
+    try:
+        download_artifacts()
+        print("Download complete!")
+    except Exception as e:
+        print(f"Download failed: {e}")
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    main()

flashinfer-cubin/flashinfer_cubin/__init__.py

@@ -0,0 +1,67 @@
+"""
+Copyright (c) 2025 by FlashInfer team.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+"""
+
+import os
+from pathlib import Path
+
+# Get the path to the cubins directory within this package
+CUBIN_DIR = Path(__file__).parent / "cubins"
+
+
+def get_cubin_dir():
+    """Get the directory containing the cubins."""
+    return str(CUBIN_DIR)
+
+
+def list_cubins():
+    """List all available cubin files."""
+    if not CUBIN_DIR.exists():
+        return []
+
+    cubins = []
+    for root, _, files in os.walk(CUBIN_DIR):
+        for file in files:
+            if file.endswith(".cubin"):
+                rel_path = os.path.relpath(os.path.join(root, file), CUBIN_DIR)
+                cubins.append(rel_path)
+    return sorted(cubins)
+
+
+def get_cubin_path(relative_path):
+    """Get the absolute path to a specific cubin file."""
+    return str(CUBIN_DIR / relative_path)
+
+
+# Read version from build metadata or fallback to main flashinfer version.txt
+def _get_version():
+    # First try to read from build metadata (for wheel distributions)
+    try:
+        from . import _build_meta
+
+        return _build_meta.__version__
+    except ImportError:
+        pass
+
+    # Fallback to reading from the main flashinfer version.txt (for development)
+    version_file = Path(__file__).parent.parent.parent / "version.txt"
+    if version_file.exists():
+        with open(version_file, "r") as f:
+            return f.read().strip()
+    return "0.0.0"
+
+
+__version__ = _get_version()
+__all__ = ["get_cubin_dir", "list_cubins", "get_cubin_path", "CUBIN_DIR"]

flashinfer-cubin/pyproject.toml

@@ -0,0 +1,54 @@
+[build-system]
+requires = ["setuptools>=61.0", "wheel", "requests", "filelock", "torch", "tqdm"] # NOTE(Zihao): we should remove torch once https://github.com/flashinfer-ai/flashinfer/pull/1641 merged
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "flashinfer-cubin"
+dynamic = ["version"]
+description = "Pre-compiled cubins for FlashInfer"
+readme = {text = "This package contains pre-compiled CUDA kernels (cubins) for FlashInfer. It provides all necessary cubin files downloaded from the FlashInfer artifactory.", content-type = "text/plain"}
+requires-python = ">=3.8"
+license = {text = "Apache-2.0"}
+authors = [
+    {name = "FlashInfer team"},
+]
+maintainers = [
+    {name = "FlashInfer team"},
+]
+classifiers = [
+    "Development Status :: 4 - Beta",
+    "Intended Audience :: Developers",
+    "License :: OSI Approved :: Apache Software License",
+    "Operating System :: OS Independent",
+    "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.8",
+    "Programming Language :: Python :: 3.9",
+    "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
+    "Programming Language :: Python :: 3.12",
+    "Topic :: Software Development :: Libraries :: Python Modules",
+]
+dependencies = [
+    "requests",
+    "filelock",
+]
+
+[project.urls]
+Homepage = "https://github.com/flashinfer-ai/flashinfer"
+Documentation = "https://github.com/flashinfer-ai/flashinfer"
+Repository = "https://github.com/flashinfer-ai/flashinfer"
+"Issue Tracker" = "https://github.com/flashinfer-ai/flashinfer/issues"
+
+[tool.setuptools]
+packages = ["flashinfer_cubin"]
+include-package-data = true
+
+[tool.setuptools.dynamic]
+version = {attr = "flashinfer_cubin.__version__"}
+
+[tool.setuptools.package-data]
+flashinfer_cubin = ["cubins/**/*"]
+
+[tool.setuptools.cmdclass]
+build_py = "setup.DownloadAndBuildPy"
+sdist = "setup.CustomSdist"