Revert "add unit test for preferred_blas_library settings (#150581)"

pytorchmergebot · pytorchmergebot · commit b0e28f60df69 · 2025-04-03T23:51:49.000Z
This reverts commit 781d28e. Reverted #150581 on behalf of https://github.com/clee2000 due to new test broken internally D72395624 ([comment](#150581 (comment)))
diff --git a/test/test_cuda.py b/test/test_cuda.py
@@ -595,64 +595,6 @@ def test_serialization_array_with_storage(self):
         q_copy[1].fill_(10)
         self.assertEqual(q_copy[3], torch.cuda.IntStorage(10).fill_(10))
 
-    @setBlasBackendsToDefaultFinally
-    def test_preferred_blas_library_settings(self):
-        def _check_default():
-            default = torch.backends.cuda.preferred_blas_library()
-            if torch.version.cuda:
-                # CUDA logic is easy, it's always cublas
-                self.assertTrue(default == torch._C._BlasBackend.Cublas)
-            else:
-                # ROCm logic is less so, it's cublaslt for some Instinct, cublas for all else
-                gcn_arch = str(
-                    torch.cuda.get_device_properties(0).gcnArchName.split(":", 1)[0]
-                )
-                if gcn_arch in ["gfx90a", "gfx942", "gfx950"]:
-                    self.assertTrue(default == torch._C._BlasBackend.Cublaslt)
-                else:
-                    self.assertTrue(default == torch._C._BlasBackend.Cublas)
-
-        _check_default()
-        # "Default" can be set but is immediately reset internally to the actual default value.
-        self.assertTrue(
-            torch.backends.cuda.preferred_blas_library("default")
-            != torch._C._BlasBackend.Default
-        )
-        _check_default()
-        self.assertTrue(
-            torch.backends.cuda.preferred_blas_library("cublas")
-            == torch._C._BlasBackend.Cublas
-        )
-        self.assertTrue(
-            torch.backends.cuda.preferred_blas_library("hipblas")
-            == torch._C._BlasBackend.Cublas
-        )
-        # check bad strings
-        with self.assertRaisesRegex(
-            RuntimeError,
-            "Unknown input value. Choose from: default, cublas, hipblas, cublaslt, hipblaslt, ck.",
-        ):
-            torch.backends.cuda.preferred_blas_library("unknown")
-        # check bad input type
-        with self.assertRaisesRegex(RuntimeError, "Unknown input value type."):
-            torch.backends.cuda.preferred_blas_library(1.0)
-        # check env var override
-        custom_envs = [
-            {"TORCH_BLAS_PREFER_CUBLASLT": "1"},
-            {"TORCH_BLAS_PREFER_HIPBLASLT": "1"},
-        ]
-        test_script = "import torch;print(torch.backends.cuda.preferred_blas_library())"
-        for env_config in custom_envs:
-            env = os.environ.copy()
-            for key, value in env_config.items():
-                env[key] = value
-            r = (
-                subprocess.check_output([sys.executable, "-c", test_script], env=env)
-                .decode("ascii")
-                .strip()
-            )
-            self.assertEqual("_BlasBackend.Cublaslt", r)
-
     @unittest.skipIf(TEST_CUDAMALLOCASYNC, "temporarily disabled for async")
     @setBlasBackendsToDefaultFinally
     def test_cublas_workspace_explicit_allocation(self):
