Revert "[cutlass backend] re-add pip cutlass path (#160180)"

This reverts commit d556586448.

Reverted https://github.com/pytorch/pytorch/pull/160180 on behalf of https://github.com/atalman due to broke macos nightly ([comment](https://github.com/pytorch/pytorch/pull/160180#issuecomment-3192311552))

torch/_inductor/codecache.py

@@ -3546,15 +3546,13 @@ def _cuda_compiler() -> Optional[str]:
     return "nvcc"
 
 
-def _cutlass_path() -> Optional[str]:
+def _cutlass_path() -> str:
     if config.is_fbcode():
         from libfb.py import parutil
 
         return parutil.get_dir_path("cutlass-4-headers")
     else:
-        from torch._inductor.codegen.cuda.cutlass_utils import try_import_cutlass
-
-        return config.cuda.cutlass_dir if try_import_cutlass() else None
+        return config.cuda.cutlass_dir
 
 
 def _cutlass_paths() -> list[str]:
@@ -3569,8 +3567,6 @@ def _cutlass_paths() -> list[str]:
 def _clone_cutlass_paths(build_root: str) -> list[str]:
     paths = _cutlass_paths()
     cutlass_root = _cutlass_path()
-    if cutlass_root is None:
-        return []
     for path in _cutlass_paths():
         old_path = os.path.join(cutlass_root, path)
         new_path = os.path.join(build_root, path)
@@ -3579,12 +3575,10 @@ def _clone_cutlass_paths(build_root: str) -> list[str]:
 
 
 def _cutlass_include_paths() -> list[str]:
-    cutlass_root = _cutlass_path()
-    if cutlass_root is None:
-        return []
+    cutlass_path = _cutlass_path()
     return [
         # Use realpath to get canonical absolute paths, in order not to mess up cache keys
-        os.path.realpath(os.path.join(cutlass_root, path))
+        os.path.realpath(os.path.join(cutlass_path, path))
         for path in _cutlass_paths()
     ]
 

torch/_inductor/codegen/cuda/cutlass_utils.py

@@ -1,7 +1,6 @@
 # mypy: allow-untyped-defs
 import atexit
 import functools
-import importlib.metadata
 import logging
 import os
 import shutil
@@ -12,7 +11,6 @@ from pathlib import Path
 from typing import Any, Optional
 
 import sympy
-from packaging.version import Version
 
 import torch
 from torch._inductor.runtime.runtime_utils import dynamo_timed
@@ -75,9 +73,7 @@ def try_import_cutlass() -> bool:
     """
     We want to support three ways of passing in CUTLASS:
     1. fbcode, handled by the internal build system.
-    2. pip install nvidia-cutlass, which provides the cutlass_library package
-       and the header files in the cutlass_library/source directory.
-    3. User specifies cutlass_dir. The default is ../third_party/cutlass/,
+    2. User specifies cutlass_dir. The default is ../third_party/cutlass/,
        which is the directory when developers build from source.
     """
     if config.is_fbcode():
@@ -93,34 +89,6 @@ def try_import_cutlass() -> bool:
 
         return True
 
-    try:
-        cutlass_version = Version(importlib.metadata.version("cutlass"))
-        if cutlass_version < Version("3.7"):
-            log.warning("CUTLASS version < 3.7 is not recommended.")
-
-        import cutlass_library  # type: ignore[import-not-found]  # noqa: F811
-
-        log.debug(
-            "Found cutlass_library in python search path, overriding config.cuda.cutlass_dir"
-        )
-        cutlass_library_dir = os.path.dirname(cutlass_library.__file__)
-        assert os.path.isdir(cutlass_library_dir), (
-            f"{cutlass_library_dir} is not a directory"
-        )
-        config.cuda.cutlass_dir = os.path.abspath(
-            os.path.join(
-                cutlass_library_dir,
-                "source",
-            )
-        )
-
-        return True
-    except (ModuleNotFoundError, importlib.metadata.PackageNotFoundError):
-        log.debug(
-            "cutlass_library not found in sys.path, trying to import from config.cuda.cutlass_dir",
-            exc_info=True,
-        )
-
     # Copy CUTLASS python scripts to a temp dir and add the temp dir to Python search path.
     # This is a temporary hack to avoid CUTLASS module naming conflicts.
     # TODO(ipiszy): remove this hack when CUTLASS solves Python scripts packaging structure issues.
@@ -188,7 +156,7 @@ def try_import_cutlass() -> bool:
                 )
 
         try:
-            import cutlass  # noqa: F401
+            import cutlass  # noqa: F401, F811
             import cutlass_library.generator  # noqa: F401
             import cutlass_library.library  # noqa: F401
             import cutlass_library.manifest  # noqa: F401