[Refactor] Remove Duplicate per_block_cast_to_fp8, Remove Dependencies of DeepGEMM (#21787)

Signed-off-by: yewentao256 <zhyanwentao@126.com>
This commit is contained in:
Wentao Ye
2025-07-31 21:13:27 -04:00
committed by GitHub
parent 0bd409cf01
commit 3700642013
8 changed files with 55 additions and 132 deletions

View File

@@ -4,49 +4,16 @@
# ruff: noqa: E501
import time
# Import DeepGEMM functions
import deep_gemm
import torch
from deep_gemm import calc_diff, ceil_div, get_col_major_tma_aligned_tensor
# Import vLLM functions
from vllm import _custom_ops as ops
from vllm.model_executor.layers.quantization.utils.fp8_utils import (
get_col_major_tma_aligned_tensor,
per_token_group_quant_fp8,
w8a8_block_fp8_matmul,
)
from vllm.triton_utils import triton
# Copied from
# https://github.com/deepseek-ai/DeepGEMM/blob/78cacf70d41d15d688bd493ebc85845f7f2a3d5d/tests/test_core.py#L9
def per_token_cast_to_fp8(
x: torch.Tensor) -> tuple[torch.Tensor, torch.Tensor]:
"""Convert tensor to FP8 format with per-token scaling."""
assert x.dim() == 2 and x.size(1) % 128 == 0
m, n = x.shape
x_view = x.view(m, -1, 128)
x_amax = x_view.abs().float().amax(dim=2).view(m, -1).clamp(1e-4)
return (x_view * (448.0 / x_amax.unsqueeze(2))).to(
torch.float8_e4m3fn).view(m, n), (x_amax / 448.0).view(m, -1)
# Copied from
# https://github.com/deepseek-ai/DeepGEMM/blob/78cacf70d41d15d688bd493ebc85845f7f2a3d5d/tests/test_core.py#L17
def per_block_cast_to_fp8(
x: torch.Tensor) -> tuple[torch.Tensor, torch.Tensor]:
"""Convert tensor to FP8 format with per-block scaling."""
assert x.dim() == 2
m, n = x.shape
x_padded = torch.zeros((ceil_div(m, 128) * 128, ceil_div(n, 128) * 128),
dtype=x.dtype,
device=x.device)
x_padded[:m, :n] = x
x_view = x_padded.view(-1, 128, x_padded.size(1) // 128, 128)
x_amax = x_view.abs().float().amax(dim=(1, 3), keepdim=True).clamp(1e-4)
x_scaled = (x_view * (448.0 / x_amax)).to(torch.float8_e4m3fn)
return x_scaled.view_as(x_padded)[:m, :n].contiguous(), (
x_amax / 448.0).view(x_view.size(0), x_view.size(2))
from vllm.utils.deep_gemm import calc_diff, fp8_gemm_nt, per_block_cast_to_fp8
def benchmark_shape(m: int,
@@ -69,14 +36,14 @@ def benchmark_shape(m: int,
# Pre-quantize B for all implementations
# (weights can be pre-quantized offline)
B_deepgemm, B_scale_deepgemm = per_block_cast_to_fp8(B)
B_vllm, B_scale_vllm = per_block_cast_to_fp8(B)
B_deepgemm, B_scale_deepgemm = per_block_cast_to_fp8(B, [128, 128], use_ue8m0=True)
B_vllm, B_scale_vllm = per_block_cast_to_fp8(B, [128, 128], use_ue8m0=True)
# Block size configuration
block_size = [128, 128]
# Pre-quantize A for all implementations
A_deepgemm, A_scale_deepgemm = per_token_cast_to_fp8(A)
A_deepgemm, A_scale_deepgemm = per_token_group_quant_fp8(A, block_size[1])
A_scale_deepgemm = get_col_major_tma_aligned_tensor(A_scale_deepgemm)
C_deepgemm = torch.empty((m, n), device='cuda', dtype=torch.bfloat16)
A_vllm, A_scale_vllm = per_token_group_quant_fp8(A, block_size[1])
@@ -85,7 +52,7 @@ def benchmark_shape(m: int,
# === DeepGEMM Implementation ===
def deepgemm_gemm():
deep_gemm.gemm_fp8_fp8_bf16_nt((A_deepgemm, A_scale_deepgemm),
fp8_gemm_nt((A_deepgemm, A_scale_deepgemm),
(B_deepgemm, B_scale_deepgemm),
C_deepgemm)
return C_deepgemm