Files
vllm/tests/kernels/moe/test_batched_moe.py
Bill Nell 922165cba3 fp8 + pplx tests + fixes
Signed-off-by: Bill Nell <bnell@redhat.com>
2025-05-29 21:25:33 +00:00

406 lines
14 KiB
Python

# SPDX-License-Identifier: Apache-2.0
from dataclasses import dataclass
from typing import Optional
import pytest
import torch
import triton.language as tl
import vllm._custom_ops as ops
from vllm.config import VllmConfig, set_current_vllm_config
from vllm.model_executor.layers.activation import SiluAndMul
from vllm.model_executor.layers.fused_moe.fused_batched_moe import (
BatchedPrepareAndFinalize, BatchedTritonExperts,
invoke_moe_batched_triton_kernel)
from vllm.model_executor.layers.fused_moe.fused_moe import fused_topk
from vllm.model_executor.layers.fused_moe.modular_kernel import (
FusedMoEModularKernel)
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 round_up
NUM_EXPERTS = [8, 64]
TOP_KS = [1, 2, 6]
vllm_config = VllmConfig()
vllm_config.scheduler_config.max_num_seqs = 128
vllm_config.scheduler_config.max_model_len = 8192
@dataclass
class BatchedMMConfig:
in_dtype: torch.dtype
out_dtype: torch.dtype
num_experts: int
max_tokens_per_expert: int
K: int
N: int
@dataclass
class BatchedMMTensors:
A: torch.Tensor # [E, max_tokens, K]
B: torch.Tensor # [E, K, N] - column major
C: torch.Tensor # [E, max_tokens, N]
num_expert_tokens: torch.Tensor # [E]
@staticmethod
def make_tensors(config: BatchedMMConfig):
if config.in_dtype == torch.torch.float8_e4m3fn:
config_in_dtype = torch.bfloat16
else:
config_in_dtype = config.in_dtype
A = torch.randn(
(config.num_experts, config.max_tokens_per_expert, config.K),
device="cuda",
dtype=config_in_dtype) / 10
B = torch.randn((config.num_experts, config.N, config.K),
device="cuda",
dtype=config_in_dtype)
C = torch.zeros(
(config.num_experts, config.max_tokens_per_expert, config.N),
device="cuda",
dtype=config.out_dtype)
A = A.to(config.in_dtype)
B = B.to(config.in_dtype)
num_expert_tokens = torch.randint(low=0,
high=config.max_tokens_per_expert,
size=(config.num_experts, ),
device="cuda",
dtype=torch.int32)
return BatchedMMTensors(A, B, C, num_expert_tokens)
def native_w8a8_block_matmul(A: torch.Tensor,
B: torch.Tensor,
As: torch.Tensor,
Bs: torch.Tensor,
block_size,
output_dtype=torch.bfloat16):
"""This function performs matrix multiplication with block-wise
quantization using native torch.
It is agnostic to the input data type and can be used for both int8 and
fp8 data types.
It takes two input tensors `A` and `B` (int8) with scales `As` and
`Bs` (float32).
The output is returned in the specified `output_dtype`.
"""
A = A.to(torch.float32)
B = B.to(torch.float32).contiguous()
assert A.shape[-1] == B.shape[-1]
assert B.ndim == 2 and B.is_contiguous() and Bs.ndim == 2
assert len(block_size) == 2
block_n, block_k = block_size[0], block_size[1]
assert (A.shape[-1] + block_k - 1) // block_k == As.shape[-1], (
f"{(A.shape[-1] + block_k - 1) // block_k} == {As.shape[-1]}")
assert A.shape[:-1] == As.shape[:-1], f"{A.shape} == {As.shape}"
M = A.numel() // A.shape[-1]
N, K = B.shape
origin_C_shape = A.shape[:-1] + (N, )
A = A.reshape(M, A.shape[-1])
As = As.reshape(M, As.shape[-1])
n_tiles = (N + block_n - 1) // block_n
k_tiles = (K + block_k - 1) // block_k
assert n_tiles == Bs.shape[0]
assert k_tiles == Bs.shape[1]
C_shape = (M, N)
C = torch.zeros(C_shape, dtype=torch.float32, device=A.device)
A_tiles = [
A[:, i * block_k:min((i + 1) * block_k, K)] for i in range(k_tiles)
]
B_tiles = [[
B[
j * block_n:min((j + 1) * block_n, N),
i * block_k:min((i + 1) * block_k, K),
] for i in range(k_tiles)
] for j in range(n_tiles)]
C_tiles = [
C[:, j * block_n:min((j + 1) * block_n, N)] for j in range(n_tiles)
]
As_tiles = [As[:, i:i + 1] for i in range(k_tiles)]
for i in range(k_tiles):
for j in range(n_tiles):
a = A_tiles[i]
b = B_tiles[j][i]
c = C_tiles[j]
s = As_tiles[i] * Bs[j][i]
c[:, :] += torch.matmul(a, b.t()) * s
C = C.reshape(origin_C_shape).to(output_dtype)
return C
def ref_impl(
A: torch.Tensor,
B: torch.Tensor,
C: torch.Tensor,
num_expert_tokens: torch.Tensor,
A_scale: Optional[torch.Tensor],
B_scale: Optional[torch.Tensor],
block_shape: Optional[list[int]],
) -> torch.Tensor:
num_expert_tokens_cpu = num_expert_tokens.clone()
num_expert_tokens_cpu = num_expert_tokens_cpu.to(device="cpu")
num_experts = num_expert_tokens.size(0)
for e in range(num_experts):
num_tokens = num_expert_tokens_cpu[e]
if A.dtype == torch.torch.float8_e4m3fn:
if False:
tmp = native_w8a8_block_matmul(A[e, :, :],
B[e].transpose(0, 1), A_scale,
B_scale, block_shape)
else:
tmp = ops.cutlass_scaled_mm(A[e, :, :], B[e].transpose(0, 1),
A_scale, B_scale, torch.bfloat16)
C[e, :num_tokens, :] = tmp[:num_tokens, :]
else:
C[e, :num_tokens, :] = A[e, :num_tokens, :] @ B[e].transpose(0, 1)
return C
@pytest.mark.parametrize("num_experts", [16, 32])
@pytest.mark.parametrize("max_tokens_per_expert",
[32, 64, 128, 192, 224, 256, 512])
@pytest.mark.parametrize("K", [128, 256, 1024])
@pytest.mark.parametrize("N", [128, 256, 512, 1024])
@pytest.mark.parametrize(
"dtype",
[torch.torch.float8_e4m3fn, torch.float32, torch.float16, torch.bfloat16])
def test_batched_mm(num_experts: int, max_tokens_per_expert: int, K: int,
N: int, dtype: torch.dtype):
if dtype == torch.torch.float8_e4m3fn:
in_dtype = dtype
out_dtype = torch.bfloat16
else:
in_dtype = dtype
out_dtype = dtype
config = BatchedMMConfig(in_dtype, out_dtype, num_experts,
max_tokens_per_expert, K, N)
tensors = BatchedMMTensors.make_tensors(config)
test_output = tensors.C
ref_output = test_output.clone()
ref_output2 = test_output.clone()
compute_tl_dtype = {
torch.float16: tl.float16,
torch.bfloat16: tl.bfloat16,
torch.float32: tl.float32
}[test_output.dtype]
use_fp8_w8a8 = dtype == torch.torch.float8_e4m3fn
block_shape = [16, 16, 32] # 16 for k if not fp8
if use_fp8_w8a8:
A_scale = torch.ones(1, dtype=torch.float32, device=tensors.A.device)
B_scale = torch.ones(1, dtype=torch.float32, device=tensors.B.device)
quant_block_shape = [1, 1]
else:
A_scale = None
B_scale = None
quant_block_shape = None
invoke_moe_batched_triton_kernel(
tensors.A,
tensors.B,
test_output,
tensors.num_expert_tokens,
compute_tl_dtype,
# Quantization data
A_scale,
B_scale,
None,
# Quantization schemes
use_fp8_w8a8,
False,
False,
config={
"BLOCK_SIZE_M": block_shape[0],
"BLOCK_SIZE_N": block_shape[1],
"BLOCK_SIZE_K": block_shape[2],
},
block_shape=quant_block_shape,
)
ref_output = ref_output.to(dtype=out_dtype)
ref_output = ref_impl(tensors.A.to(dtype=out_dtype),
tensors.B.to(dtype=out_dtype), ref_output,
tensors.num_expert_tokens, A_scale, B_scale,
block_shape[-2:])
ref_output2 = ref_impl(tensors.A, tensors.B, ref_output2,
tensors.num_expert_tokens, A_scale, B_scale,
block_shape[-2:])
rtol, atol = {
torch.float16: (6e-2, 6e-2),
torch.bfloat16: (6e-2, 6e-2),
torch.float32: (1e-2, 1e-2),
}[test_output.dtype]
torch.testing.assert_close(ref_output, ref_output2, atol=atol, rtol=rtol)
torch.testing.assert_close(test_output, ref_output2, atol=atol, rtol=rtol)
def batched_moe(
a: torch.Tensor,
w1: torch.Tensor,
w2: torch.Tensor,
topk_weight: torch.Tensor,
topk_ids: torch.Tensor,
w1_scale: Optional[torch.Tensor] = None,
w2_scale: Optional[torch.Tensor] = None,
qtype: Optional[torch.dtype] = None,
block_shape: Optional[list[int]] = None,
per_act_token: bool = False,
) -> torch.Tensor:
max_num_tokens = round_up(a.shape[0], 64)
fused_experts = FusedMoEModularKernel(
BatchedPrepareAndFinalize(max_num_tokens,
world_size=1,
dp_size=1,
rank=0,
qtype=qtype,
block_shape=block_shape,
per_act_token=per_act_token),
BatchedTritonExperts(max_num_tokens=max_num_tokens,
dp_size=1,
world_size=1,
use_fp8_w8a8=qtype == torch.float8_e4m3fn,
block_shape=block_shape))
return fused_experts(a,
w1,
w2,
topk_weight,
topk_ids,
w1_scale=w1_scale,
w2_scale=w2_scale)
# Note: same as torch_moe but with fused_topk factored out.
def torch_moe2(
a: torch.Tensor,
w1: torch.Tensor,
w2: torch.Tensor,
topk_weight: torch.Tensor,
topk_ids: torch.Tensor,
w1_scale: Optional[torch.Tensor] = None,
w2_scale: Optional[torch.Tensor] = None,
use_fp8_w8a8: bool = False,
block_shape: Optional[list[int]] = None,
) -> torch.Tensor:
M, K = a.shape
topk = topk_ids.shape[1]
a = a.view(M, -1, K).repeat(1, topk, 1).reshape(-1, K)
if use_fp8_w8a8:
a, a_scale = per_token_group_quant_fp8(a, block_shape[1])
else:
a_scale = None
out = torch.zeros(M * topk,
w2.shape[1],
dtype=torch.bfloat16,
device=a.device)
num_experts = w1.shape[0]
for i in range(num_experts):
mask = (topk_ids == i).view(-1)
if mask.sum():
if not use_fp8_w8a8:
tmp1 = a[mask] @ w1[i].transpose(0, 1)
tmp2 = SiluAndMul()(tmp1)
out[mask] = tmp2 @ w2[i].transpose(0, 1)
else:
tmp1 = native_w8a8_block_matmul(a[mask], w1[i], a_scale[mask],
w1_scale[i], block_shape,
torch.bfloat16)
tmp2 = SiluAndMul()(tmp1)
tmp2, b_scale = per_token_group_quant_fp8(tmp2, block_shape[1])
out[mask] = native_w8a8_block_matmul(tmp2, w2[i], b_scale,
w2_scale[i], block_shape,
torch.bfloat16)
return (out.view(M, -1, w2.shape[1]) *
topk_weight.view(M, -1, 1).to(out.dtype)).sum(dim=1)
@pytest.mark.parametrize("m", [32, 45, 64]) #[1, 33, 64, 222])
@pytest.mark.parametrize("n", [128, 512, 1024, 2048])
@pytest.mark.parametrize("k", [128, 512, 1024, 2048])
@pytest.mark.parametrize("e", NUM_EXPERTS)
@pytest.mark.parametrize("topk", TOP_KS)
@pytest.mark.parametrize("dtype", [torch.float8_e4m3fn, torch.bfloat16])
def test_fused_moe_batched_experts(
m: int,
n: int,
k: int,
e: int,
topk: int,
dtype: torch.dtype,
):
current_platform.seed_everything(7)
block_shape = [128, 128]
a = torch.randn((m, k), device="cuda", dtype=torch.bfloat16) / 10
w1 = torch.randn((e, 2 * n, k), device="cuda", dtype=torch.bfloat16) / 10
w2 = torch.randn((e, k, n), device="cuda", dtype=torch.bfloat16) / 10
score = torch.randn((m, e), device="cuda", dtype=torch.bfloat16)
use_fp8_w8a8 = dtype == torch.torch.float8_e4m3fn
qtype = dtype if dtype == torch.torch.float8_e4m3fn else None
if use_fp8_w8a8:
block_n, block_k = block_shape[0], block_shape[1]
n_tiles_w1 = (2 * n + block_n - 1) // block_n
n_tiles_w2 = (k + block_n - 1) // block_n
k_tiles_w1 = (k + block_k - 1) // block_k
k_tiles_w2 = (n + block_k - 1) // block_k
finfo = torch.finfo(dtype)
fp8_min = finfo.min
fp8_max = finfo.max
w1 = w1.clamp(min=fp8_min, max=fp8_max).to(dtype)
w2 = w2.clamp(min=fp8_min, max=fp8_max).to(dtype)
factor_for_scale = 1e-2
w1_s = torch.rand(
(e, n_tiles_w1, k_tiles_w1), dtype=torch.float32,
device="cuda") * factor_for_scale
w2_s = torch.rand(
(e, n_tiles_w2, k_tiles_w2), dtype=torch.float32,
device="cuda") * factor_for_scale
else:
w1_s = None
w2_s = None
with set_current_vllm_config(vllm_config):
topk_weight, topk_ids, _ = fused_topk(a, score, topk, False)
batched_output = batched_moe(a, w1, w2, topk_weight, topk_ids, w1_s,
w2_s, qtype, block_shape)
baseline_output = torch_moe2(a, w1, w2, topk_weight, topk_ids, w1_s,
w2_s, use_fp8_w8a8, block_shape)
torch.testing.assert_close(baseline_output,
batched_output,
atol=2e-2,
rtol=0)