[Refactor] Remove DeepGEMM OP Register (#25710)

Signed-off-by: yewentao256 <zhyanwentao@126.com>

vllm/model_executor/layers/quantization/deepgemm.py

-# SPDX-License-Identifier: Apache-2.0
-# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
-import logging
-
-import torch
-
-from vllm.triton_utils import triton
-from vllm.utils import direct_register_custom_op
-from vllm.utils.deep_gemm import fp8_gemm_nt
-
-logger = logging.getLogger(__name__)
-
-
-def prepare_block_fp8_matmul_inputs(
-    A: torch.Tensor,
-    B: torch.Tensor,
-    As: torch.Tensor,
-    Bs: torch.Tensor,
-    block_size: list[int],
-    output_dtype: torch.dtype = torch.float16,
-) -> tuple[int, int, int, torch.Tensor]:
-    assert len(block_size) == 2
-    block_n, block_k = block_size[0], block_size[1]
-
-    assert A.shape[-1] == B.shape[-1]
-    assert A.shape[:-1] == As.shape[:-1]
-    assert A.is_contiguous()
-    assert triton.cdiv(A.shape[-1], block_k) == As.shape[-1]
-
-    M = A.numel() // A.shape[-1]
-
-    assert B.ndim == 2
-    assert B.is_contiguous()
-    assert Bs.ndim == 2
-    N, K = B.shape
-    assert triton.cdiv(N, block_n) == Bs.shape[0]
-    assert triton.cdiv(K, block_k) == Bs.shape[1]
-
-    C_shape = A.shape[:-1] + (N, )
-    C = A.new_empty(C_shape, dtype=output_dtype)
-
-    return M, N, K, C
-
-
-def w8a8_block_fp8_matmul_deepgemm(
-    A: torch.Tensor,
-    B: torch.Tensor,
-    As: torch.Tensor,
-    Bs: torch.Tensor,
-    block_size: list[int],
-    output_dtype: torch.dtype,
-) -> torch.Tensor:
-    M, N, K, C = prepare_block_fp8_matmul_inputs(A, B, As, Bs, block_size,
-                                                 output_dtype)
-    # Deepgemm only supports output tensor type as bfloat16
-    assert C.dtype == torch.bfloat16
-    fp8_gemm_nt((A, As), (B, Bs), C)
-    return C
-
-
-def w8a8_block_fp8_matmul_deepgemm_fake(
-    A: torch.Tensor,
-    B: torch.Tensor,
-    As: torch.Tensor,
-    Bs: torch.Tensor,
-    block_size: list[int],
-    output_dtype: torch.dtype,
-) -> torch.Tensor:
-    M, N, K, C = prepare_block_fp8_matmul_inputs(A, B, As, Bs, block_size,
-                                                 output_dtype)
-    return C
-
-
-direct_register_custom_op(
-    op_name="w8a8_block_fp8_matmul_deepgemm",
-    op_func=w8a8_block_fp8_matmul_deepgemm,
-    fake_impl=w8a8_block_fp8_matmul_deepgemm_fake,
-)

vllm/model_executor/layers/quantization/utils/fp8_utils.py

@@ -23,7 +23,7 @@ from vllm.model_executor.parameter import (BlockQuantScaleParameter,
 from vllm.platforms import current_platform
 from vllm.triton_utils import tl, triton
 from vllm.utils import direct_register_custom_op
-from vllm.utils.deep_gemm import (is_deep_gemm_e8m0_used,
+from vllm.utils.deep_gemm import (fp8_gemm_nt, is_deep_gemm_e8m0_used,
                                   should_use_deepgemm_for_fp8_linear)
 
 logger = init_logger(__name__)
@@ -141,17 +141,10 @@ def apply_w8a8_block_fp8_linear(
             block_size[1],
             column_major_scales=True,
         )
-
-        # ensure DeepGEMM-backed custom op is registered before use
-        import vllm.model_executor.layers.quantization.deepgemm  # noqa: F401
-
-        output = torch.ops.vllm.w8a8_block_fp8_matmul_deepgemm(
-            q_input,
-            weight,
-            x_scale,
-            weight_scale,
-            block_size,
-            output_dtype=output_dtype)
+        output = torch.empty((q_input.shape[0], weight.shape[0]),
+                             dtype=torch.bfloat16,
+                             device=q_input.device)
+        fp8_gemm_nt((q_input, x_scale), (weight, weight_scale), output)
         if bias is not None:
             output += bias
         return output.to(dtype=output_dtype).view(*output_shape)