refactor apply_w8a8_block_fp8_linear in fp (#6545)

This commit is contained in:
ChangyiYang
2025-05-29 00:15:11 -07:00
committed by GitHub
parent 7e41290082
commit 485a023bd8
5 changed files with 283 additions and 120 deletions

View File

@@ -740,7 +740,59 @@ if _is_hip:
return _w8a8_block_fp8_matmul
def w8a8_block_fp8_matmul(
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]:
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 and _ENABLE_JIT_DEEPGEMM
if supports_custom_op():
torch.ops.sglang.deep_gemm_fp8_fp8_bf16_nt(A, As, B, Bs, C)
else:
deep_gemm_gemm_nt_f8f8bf16((A, As), (B, Bs), C)
return C
def w8a8_block_fp8_matmul_triton(
A: torch.Tensor,
B: torch.Tensor,
As: torch.Tensor,
@@ -764,81 +816,81 @@ def w8a8_block_fp8_matmul(
Returns:
torch.Tensor: The result of matmul.
"""
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] and A.is_contiguous()
assert triton.cdiv(A.shape[-1], block_k) == As.shape[-1]
M = A.numel() // A.shape[-1]
M, N, K, C = prepare_block_fp8_matmul_inputs(A, B, As, Bs, block_size, output_dtype)
assert B.ndim == 2 and B.is_contiguous() and 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]
block_n, block_k = block_size
C_shape = A.shape[:-1] + (N,)
C = A.new_empty(C_shape, dtype=output_dtype)
# deepgemm only support bf16
if C.dtype == torch.bfloat16 and _ENABLE_JIT_DEEPGEMM:
if supports_custom_op():
torch.ops.sglang.deep_gemm_fp8_fp8_bf16_nt(A, As, B, Bs, C)
else:
deep_gemm_gemm_nt_f8f8bf16((A, As), (B, Bs), C)
configs = get_w8a8_block_fp8_configs(N, K, block_size[0], block_size[1])
if configs:
# If an optimal configuration map has been found, look up the
# optimal config
config = configs[min(configs.keys(), key=lambda x: abs(x - M))]
else:
configs = get_w8a8_block_fp8_configs(N, K, block_size[0], block_size[1])
if configs:
# If an optimal configuration map has been found, look up the
# optimal config
config = configs[min(configs.keys(), key=lambda x: abs(x - M))]
else:
# Default config
# Block-wise quant: BLOCK_SIZE_K must be divisible by block_size[1]
config = {
"BLOCK_SIZE_M": 64,
"BLOCK_SIZE_N": block_size[0],
"BLOCK_SIZE_K": block_size[1],
"GROUP_SIZE_M": 32,
"num_warps": 4,
"num_stages": 3,
}
# Default config
# Block-wise quant: BLOCK_SIZE_K must be divisible by block_size[1]
config = {
"BLOCK_SIZE_M": 64,
"BLOCK_SIZE_N": block_size[0],
"BLOCK_SIZE_K": block_size[1],
"GROUP_SIZE_M": 32,
"num_warps": 4,
"num_stages": 3,
}
def grid(META):
return (
triton.cdiv(M, META["BLOCK_SIZE_M"])
* triton.cdiv(N, META["BLOCK_SIZE_N"]),
)
kernel = select_w8a8_block_fp8_matmul_kernel(M, N, config)
kernel[grid](
A,
B,
C,
As,
Bs,
M,
N,
K,
block_n,
block_k,
A.stride(-2),
A.stride(-1),
B.stride(1),
B.stride(0),
C.stride(-2),
C.stride(-1),
As.stride(-2),
As.stride(-1),
Bs.stride(1),
Bs.stride(0),
**config,
def grid(META):
return (
triton.cdiv(M, META["BLOCK_SIZE_M"]) * triton.cdiv(N, META["BLOCK_SIZE_N"]),
)
kernel = select_w8a8_block_fp8_matmul_kernel(M, N, config)
kernel[grid](
A,
B,
C,
As,
Bs,
M,
N,
K,
block_n,
block_k,
A.stride(-2),
A.stride(-1),
B.stride(1),
B.stride(0),
C.stride(-2),
C.stride(-1),
As.stride(-2),
As.stride(-1),
Bs.stride(1),
Bs.stride(0),
**config,
)
return C
# universal entry point, for testing purposes
def w8a8_block_fp8_matmul(
A: torch.Tensor,
B: torch.Tensor,
As: torch.Tensor,
Bs: torch.Tensor,
block_size: List[int],
output_dtype: torch.dtype = torch.float16,
) -> torch.Tensor:
if output_dtype == torch.bfloat16 and _ENABLE_JIT_DEEPGEMM:
return w8a8_block_fp8_matmul_deepgemm(
A, B, As, Bs, block_size, output_dtype=output_dtype
)
return w8a8_block_fp8_matmul_triton(
A, B, As, Bs, block_size, output_dtype=output_dtype
)
@triton.jit
def _per_tensor_quant_mla_fp8_stage1(
x_ptr,