[Refactor] Create a function util and cache the results for has_deepgemm, has_deepep, has_pplx (#20187)

yewentao256 · web-flow · commit 4d3669368753 · 2025-06-28T22:06:38.000Z
Signed-off-by: yewentao256 &lt;zhyanwentao@126.com&gt;
diff --git a/tests/kernels/moe/test_deepep_deepgemm_moe.py b/tests/kernels/moe/test_deepep_deepgemm_moe.py
@@ -6,7 +6,6 @@
 """
 
 import dataclasses
-import importlib
 from typing import Optional
 
 import pytest
@@ -21,38 +20,33 @@
 from vllm.model_executor.layers.quantization.utils.fp8_utils import (
     per_token_group_quant_fp8)
 from vllm.platforms import current_platform
+from vllm.utils import has_deep_ep, has_deep_gemm
 
 from .utils import ProcessGroupInfo, parallel_launch
 
-has_deep_ep = importlib.util.find_spec("deep_ep") is not None
-
-try:
-    import deep_gemm
-    has_deep_gemm = True
-except ImportError:
-    has_deep_gemm = False
-
-if has_deep_ep:
+if has_deep_ep():
     from vllm.model_executor.layers.fused_moe.deepep_ht_prepare_finalize import (  # noqa: E501
         DeepEPHTPrepareAndFinalize)
     from vllm.model_executor.layers.fused_moe.deepep_ll_prepare_finalize import (  # noqa: E501
         DeepEPLLPrepareAndFinalize)
 
     from .deepep_utils import DeepEPHTArgs, DeepEPLLArgs, make_deepep_a2a
 
-if has_deep_gemm:
+if has_deep_gemm():
+    import deep_gemm
+
     from vllm.model_executor.layers.fused_moe.batched_deep_gemm_moe import (
         BatchedDeepGemmExperts)
     from vllm.model_executor.layers.fused_moe.deep_gemm_moe import (
         DeepGemmExperts)
 
 requires_deep_ep = pytest.mark.skipif(
-    not has_deep_ep,
+    not has_deep_ep(),
     reason="Requires deep_ep kernels",
 )
 
 requires_deep_gemm = pytest.mark.skipif(
-    not has_deep_gemm,
+    not has_deep_gemm(),
     reason="Requires deep_gemm kernels",
 )
 
diff --git a/tests/kernels/moe/test_deepep_moe.py b/tests/kernels/moe/test_deepep_moe.py
@@ -4,7 +4,6 @@
 """
 
 import dataclasses
-import importlib
 from typing import Optional, Union
 
 import pytest
@@ -22,12 +21,11 @@
 from vllm.model_executor.layers.quantization.utils.fp8_utils import (
     per_token_group_quant_fp8)
 from vllm.platforms import current_platform
+from vllm.utils import has_deep_ep
 
 from .utils import ProcessGroupInfo, parallel_launch
 
-has_deep_ep = importlib.util.find_spec("deep_ep") is not None
-
-if has_deep_ep:
+if has_deep_ep():
     from vllm.model_executor.layers.fused_moe.deepep_ht_prepare_finalize import (  # noqa: E501
         DeepEPHTPrepareAndFinalize)
     from vllm.model_executor.layers.fused_moe.deepep_ll_prepare_finalize import (  # noqa: E501
@@ -36,7 +34,7 @@
     from .deepep_utils import DeepEPHTArgs, DeepEPLLArgs, make_deepep_a2a
 
 requires_deep_ep = pytest.mark.skipif(
-    not has_deep_ep,
+    not has_deep_ep(),
     reason="Requires deep_ep kernels",
 )
 
diff --git a/vllm/distributed/device_communicators/all2all.py b/vllm/distributed/device_communicators/all2all.py
@@ -1,13 +1,13 @@
 # SPDX-License-Identifier: Apache-2.0
 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project
-import importlib.util
 from typing import TYPE_CHECKING, Any
 
 import torch
 import torch.distributed as dist
 
 from vllm.forward_context import get_forward_context
 from vllm.logger import init_logger
+from vllm.utils import has_deep_ep, has_pplx
 
 from .base_device_communicator import All2AllManagerBase, Cache
 
@@ -80,8 +80,8 @@ class PPLXAll2AllManager(All2AllManagerBase):
     """
 
     def __init__(self, cpu_group):
-        has_pplx = importlib.util.find_spec("pplx_kernels") is not None
-        assert has_pplx, "pplx_kernels not found. Please follow https://github.com/vllm-project/vllm/blob/main/tools/ep_kernels/README.md to install pplx_kernels."  # noqa
+        assert has_pplx(
+        ), "pplx_kernels not found. Please follow https://github.com/vllm-project/vllm/blob/main/tools/ep_kernels/README.md to install pplx_kernels."  # noqa
         super().__init__(cpu_group)
 
         if self.internode:
@@ -133,8 +133,8 @@ class DeepEPAll2AllManagerBase(All2AllManagerBase):
     """
 
     def __init__(self, cpu_group):
-        has_deepep = importlib.util.find_spec("deep_ep") is not None
-        assert has_deepep, "DeepEP kernels not found. Please follow https://github.com/vllm-project/vllm/blob/main/tools/ep_kernels/README.md to install DeepEP kernels."  # noqa
+        assert has_deep_ep(
+        ), "DeepEP kernels not found. Please follow https://github.com/vllm-project/vllm/blob/main/tools/ep_kernels/README.md to install DeepEP kernels."  # noqa
         super().__init__(cpu_group)
         self.handle_cache = Cache()
 
diff --git a/vllm/model_executor/layers/fused_moe/batched_deep_gemm_moe.py b/vllm/model_executor/layers/fused_moe/batched_deep_gemm_moe.py
@@ -1,5 +1,4 @@
 # SPDX-License-Identifier: Apache-2.0
-import importlib.util
 from typing import Optional
 
 import torch
@@ -11,8 +10,6 @@
 
 logger = init_logger(__name__)
 
-has_deep_gemm = importlib.util.find_spec("deep_gemm") is not None
-
 
 @triton.jit
 def _silu_mul_fp8_quant_deep_gemm(
diff --git a/vllm/model_executor/layers/fused_moe/deep_gemm_moe.py b/vllm/model_executor/layers/fused_moe/deep_gemm_moe.py
@@ -1,7 +1,6 @@
 # SPDX-License-Identifier: Apache-2.0
 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project
 import functools
-import importlib.util
 from typing import Optional
 
 import torch
@@ -12,14 +11,13 @@
     _moe_permute)
 from vllm.model_executor.layers.fused_moe.prepare_finalize import (
     MoEPrepareAndFinalizeNoEP)
-from vllm.model_executor.layers.fused_moe.utils import (
-    _resize_cache, per_token_group_quant_fp8)
-from vllm.utils import round_up
+from vllm.model_executor.layers.fused_moe.utils import _resize_cache
+from vllm.model_executor.layers.quantization.utils.fp8_utils import (
+    per_token_group_quant_fp8)
+from vllm.utils import has_deep_gemm, round_up
 
 logger = init_logger(__name__)
 
-has_deep_gemm = importlib.util.find_spec("deep_gemm") is not None
-
 
 @functools.cache
 def deep_gemm_block_shape() -> list[int]:
@@ -41,7 +39,7 @@ def _valid_deep_gemm(hidden_states: torch.Tensor, w1: torch.Tensor,
     gemm kernel.  All of M, N, K and the quantization block_shape must be
     aligned by `dg.get_m_alignment_for_contiguous_layout()`.
     """
-    if not has_deep_gemm:
+    if not has_deep_gemm():
         logger.debug("DeepGemm disabled: deep_gemm not available.")
         return False
 
diff --git a/vllm/model_executor/layers/fused_moe/layer.py b/vllm/model_executor/layers/fused_moe/layer.py
@@ -1,7 +1,6 @@
 # SPDX-License-Identifier: Apache-2.0
 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project
 
-import importlib
 from abc import abstractmethod
 from collections.abc import Iterable
 from dataclasses import dataclass
@@ -32,20 +31,17 @@
 from vllm.model_executor.utils import set_weight_attrs
 from vllm.platforms import current_platform
 from vllm.platforms.interface import CpuArchEnum
-from vllm.utils import direct_register_custom_op
-
-has_pplx = importlib.util.find_spec("pplx_kernels") is not None
-has_deepep = importlib.util.find_spec("deep_ep") is not None
+from vllm.utils import direct_register_custom_op, has_deep_ep, has_pplx
 
 if current_platform.is_cuda_alike():
     from .fused_batched_moe import BatchedTritonExperts
     from .fused_moe import TritonExperts, fused_experts
     from .modular_kernel import (FusedMoEModularKernel,
                                  FusedMoEPermuteExpertsUnpermute,
                                  FusedMoEPrepareAndFinalize)
-    if has_pplx:
+    if has_pplx():
         from .pplx_prepare_finalize import PplxPrepareAndFinalize
-    if has_deepep:
+    if has_deep_ep():
         from .deepep_ht_prepare_finalize import DeepEPHTPrepareAndFinalize
         from .deepep_ll_prepare_finalize import (DEEPEP_QUANT_BLOCK_SIZE,
                                                  DeepEPLLPrepareAndFinalize)
diff --git a/vllm/model_executor/layers/fused_moe/utils.py b/vllm/model_executor/layers/fused_moe/utils.py
@@ -104,4 +104,4 @@ def find_free_port():
     with closing(socket.socket(socket.AF_INET, socket.SOCK_STREAM)) as s:
         s.bind(('', 0))
         s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
-        return s.getsockname()[1]
+        return s.getsockname()[1]
diff --git a/vllm/model_executor/layers/quantization/compressed_tensors/compressed_tensors_moe.py b/vllm/model_executor/layers/quantization/compressed_tensors/compressed_tensors_moe.py
@@ -2,7 +2,6 @@
 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project
 
 import enum
-import importlib
 from enum import Enum
 from typing import Callable, Optional
 
@@ -29,13 +28,12 @@
 from vllm.model_executor.utils import set_weight_attrs
 from vllm.platforms import current_platform
 from vllm.scalar_type import scalar_types
-
-has_pplx = importlib.util.find_spec("pplx_kernels") is not None
+from vllm.utils import has_pplx
 
 if current_platform.is_cuda_alike():
     from vllm.model_executor.layers.fused_moe.fused_batched_moe import (
         BatchedPrepareAndFinalize)
-    if has_pplx:
+    if has_pplx():
         from vllm.model_executor.layers.fused_moe.pplx_prepare_finalize import (
             PplxPrepareAndFinalize)
 
@@ -577,7 +575,7 @@ def select_gemm_impl(self, prepare_finalize, moe):
             use_batched_format=True,
         )
 
-        if has_pplx and isinstance(
+        if has_pplx() and isinstance(
                 prepare_finalize,
             (BatchedPrepareAndFinalize, PplxPrepareAndFinalize)):
             # no expert_map support in this case
diff --git a/vllm/model_executor/layers/quantization/deepgemm.py b/vllm/model_executor/layers/quantization/deepgemm.py
@@ -1,15 +1,13 @@
 # SPDX-License-Identifier: Apache-2.0
-import importlib.util
 import logging
 
 import torch
 
 from vllm.platforms import current_platform
 from vllm.triton_utils import triton
-from vllm.utils import direct_register_custom_op
+from vllm.utils import direct_register_custom_op, has_deep_gemm
 
-has_deep_gemm = importlib.util.find_spec("deep_gemm") is not None
-if has_deep_gemm:
+if has_deep_gemm():
     import deep_gemm
 
 logger = logging.getLogger(__name__)
diff --git a/vllm/model_executor/layers/quantization/fp8.py b/vllm/model_executor/layers/quantization/fp8.py
@@ -2,7 +2,6 @@
 # SPDX-FileCopyrightText: Copyright contributors to the vLLM project
 
 import functools
-import importlib.util
 from typing import Any, Callable, Optional, Union
 
 import torch
@@ -38,13 +37,12 @@
 from vllm.model_executor.utils import set_weight_attrs
 from vllm.platforms import current_platform
 from vllm.scalar_type import scalar_types
+from vllm.utils import has_deep_gemm
 
 ACTIVATION_SCHEMES = ["static", "dynamic"]
 
 logger = init_logger(__name__)
 
-has_deep_gemm = importlib.util.find_spec("deep_gemm") is not None
-
 
 def _is_col_major(x: torch.Tensor) -> bool:
     assert x.dim() == 3
@@ -451,7 +449,7 @@ def __init__(self, quant_config: Fp8Config):
         # Check for DeepGemm support.
         self.allow_deep_gemm = False
         if envs.VLLM_USE_DEEP_GEMM:
-            if not has_deep_gemm:
+            if not has_deep_gemm():
                 logger.warning_once("Failed to import DeepGemm kernels.")
             elif not self.block_quant:
                 logger.warning_once("Model is not block quantized. Not using "
diff --git a/vllm/model_executor/layers/quantization/utils/fp8_utils.py b/vllm/model_executor/layers/quantization/utils/fp8_utils.py
@@ -3,7 +3,6 @@
 
 # Adapted from https://github.com/sgl-project/sglang/pull/2575
 import functools
-import importlib.util
 import json
 import os
 from typing import Any, Callable, Optional, Union
@@ -19,10 +18,9 @@
     CUTLASS_BLOCK_FP8_SUPPORTED)
 from vllm.platforms import current_platform
 from vllm.triton_utils import tl, triton
-from vllm.utils import cdiv, direct_register_custom_op
+from vllm.utils import cdiv, direct_register_custom_op, has_deep_gemm
 
 logger = init_logger(__name__)
-has_deep_gemm = importlib.util.find_spec("deep_gemm") is not None
 
 
 def is_fp8(x: Union[torch.dtype, torch.Tensor]) -> bool:
@@ -109,7 +107,7 @@ def should_use_deepgemm(output_dtype: torch.dtype, weight: torch.Tensor):
     """
 
     return (current_platform.is_cuda()
-            and current_platform.is_device_capability(90) and has_deep_gemm
+            and current_platform.is_device_capability(90) and has_deep_gemm()
             and envs.VLLM_USE_DEEP_GEMM and output_dtype == torch.bfloat16
             and weight.shape[0] % 128 == 0 and weight.shape[1] % 128 == 0)
 
diff --git a/vllm/utils.py b/vllm/utils.py
@@ -2929,3 +2929,31 @@ def is_torch_equal_or_newer(target: str) -> bool:
 def _is_torch_equal_or_newer(torch_version: str, target: str) -> bool:
     torch_version = version.parse(torch_version)
     return torch_version >= version.parse(target)
+
+
+@cache
+def _has_module(module_name: str) -> bool:
+    """Return True if *module_name* can be found in the current environment.
+
+    The result is cached so that subsequent queries for the same module incur
+    no additional overhead.
+    """
+    return importlib.util.find_spec(module_name) is not None
+
+
+def has_pplx() -> bool:
+    """Whether the optional `pplx_kernels` package is available."""
+
+    return _has_module("pplx_kernels")
+
+
+def has_deep_ep() -> bool:
+    """Whether the optional `deep_ep` package is available."""
+
+    return _has_module("deep_ep")
+
+
+def has_deep_gemm() -> bool:
+    """Whether the optional `deep_gemm` package is available."""
+
+    return _has_module("deep_gemm")
