vllm/tests/compile/test_fusion.py
Luka Govedič 9cdde47289
[BugFix] Fix fusion test and add them to CI (#16287)
Signed-off-by: luka <luka@neuralmagic.com>
2025-04-08 23:46:45 -07:00

131 lines
5.2 KiB
Python

# SPDX-License-Identifier: Apache-2.0
import pytest
import torch
import vllm.envs as envs
import vllm.plugins
from vllm.compilation.fusion import (FUSED_OPS, QUANT_OPS, FusedRMSQuantKey,
FusionPass, QuantKey)
from vllm.compilation.fx_utils import find_auto_fn, find_auto_fn_maybe
from vllm.compilation.noop_elimination import NoOpEliminationPass
from vllm.config import CompilationConfig, CompilationLevel, VllmConfig
from vllm.model_executor.layers.layernorm import RMSNorm
from vllm.model_executor.layers.quantization.utils.w8a8_utils import (
CUTLASS_FP8_SUPPORTED, Fp8LinearOp, maybe_create_device_identity)
from vllm.platforms import current_platform
from .backend import TestBackend
FP8_DTYPE = current_platform.fp8_dtype()
class TestModel(torch.nn.Module):
def __init__(self, hidden_size: int, eps: float, static: bool,
cutlass_fp8_enabled: bool, *args, **kwargs):
super().__init__(*args, **kwargs)
self.cutlass_fp8_enabled = cutlass_fp8_enabled
self.norm = [RMSNorm(hidden_size, eps) for _ in range(3)]
self.wscale = [torch.rand(1, dtype=torch.float32) for _ in range(2)]
if static:
self.scale = [torch.rand(1, dtype=torch.float32) for _ in range(2)]
else:
self.scale = [None for _ in range(2)]
self.w = [
torch.rand(hidden_size, hidden_size).to(dtype=FP8_DTYPE).t()
for _ in range(2)
]
self.fp8_linear = Fp8LinearOp(
cutlass_fp8_supported=cutlass_fp8_enabled,
use_per_token_if_dynamic=True)
def forward(self, x):
resid = torch.sqrt(x)
y = self.norm[0](x)
x2 = self.fp8_linear.apply(y,
self.w[0],
self.wscale[0],
input_scale=self.scale[0])
# make sure resid is used for replacement to work
y2, resid = self.norm[1](x2, resid)
x3 = self.fp8_linear.apply(y2,
self.w[1],
self.wscale[1],
input_scale=self.scale[1])
y3, resid = self.norm[2](x3, resid) # use resid here
return y3
@pytest.mark.parametrize("dtype", [torch.float16, torch.bfloat16])
@pytest.mark.parametrize("hidden_size", [64, 3392, 4096])
@pytest.mark.parametrize("num_tokens", [7, 256, 533, 2048, 2049])
@pytest.mark.parametrize("eps", [1e-5, 1e-6])
@pytest.mark.parametrize("static", [True, False])
@pytest.mark.parametrize("cutlass_fp8_enabled",
[True, False] if CUTLASS_FP8_SUPPORTED else [False])
@pytest.mark.skipif(envs.VLLM_TARGET_DEVICE not in ["cuda", "rocm"],
reason="Only test on CUDA and ROCm")
def test_fusion_rmsnorm_quant(dtype, hidden_size, num_tokens, eps, static,
cutlass_fp8_enabled):
torch.set_default_device("cuda")
torch.set_default_dtype(dtype)
torch.manual_seed(1)
maybe_create_device_identity() # needed for certain non-cutlass fp8 paths
vllm_config = VllmConfig(compilation_config=CompilationConfig(
level=CompilationLevel.PIECEWISE, custom_ops=["+rms_norm"]))
with vllm.config.set_current_vllm_config(vllm_config):
# Reshape pass is needed for the fusion pass to work
config = CompilationConfig.PassConfig(enable_fusion=True,
enable_noop=True)
noop_pass = NoOpEliminationPass(config)
fusion_pass = FusionPass.instance(config)
backend = TestBackend(noop_pass, fusion_pass)
model = TestModel(hidden_size, eps, static, cutlass_fp8_enabled)
# First dimension dynamic
x = torch.rand(num_tokens, hidden_size)
torch._dynamo.mark_dynamic(x, 0)
result = model(x)
model2 = torch.compile(model, backend=backend)
result2 = model2(x)
# Higher tol for dynamic, even higher for bfloat16
if static:
ATOL, RTOL = (1e-3, 1e-3)
elif dtype == torch.float16:
ATOL, RTOL = (2e-3, 2e-3)
else:
ATOL, RTOL = (1e-2, 1e-2)
torch.testing.assert_close(result, result2, atol=ATOL, rtol=RTOL)
# Check substitution worked
pre_nodes = backend.graph_pre_pass.nodes
post_nodes = backend.graph_post_pass.nodes
# static is per-tensor, dynamic is per-token
key = QuantKey(dtype=FP8_DTYPE,
static=static,
per_tensor=static,
symmetric=True)
rms_quant = FUSED_OPS[FusedRMSQuantKey(key, False)]
add_rms_quant = FUSED_OPS[FusedRMSQuantKey(key, True)]
fp8_quant = QUANT_OPS[key]
# In pre-nodes, fp8 quant should be there and fused kernels should not
assert find_auto_fn_maybe(pre_nodes, rms_quant) is None
assert find_auto_fn_maybe(pre_nodes, add_rms_quant) is None
find_auto_fn(pre_nodes, fp8_quant)
# In post-nodes, fused kernels should be there and fp8 quant should not
find_auto_fn(post_nodes, rms_quant)
find_auto_fn(post_nodes, add_rms_quant)
assert find_auto_fn_maybe(post_nodes, fp8_quant) is None