[kernels] Reorganize ops/diffusion by operator domain behind a lazy facade (#35114)

Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
This commit is contained in:
Xiaoyu Zhang
2026-08-18 20:37:43 +08:00
committed by GitHub
co-authored by Claude Opus 5
parent 7605529bdf
commit ae6945e112
167 changed files with 4813 additions and 4340 deletions
@@ -0,0 +1,141 @@
import sys
import pytest
import torch
from sglang.kernels.ops.quantization.fp8_kernel import static_quant_fp8
from sglang.multimodal_gen.runtime.layers.quantization.modelopt_quant import (
ModelOptFp8Config,
ModelOptFp8LinearMethod,
)
from sglang.srt.layers.quantization.fp8_utils import (
cutlass_fp8_supported,
input_to_float8,
)
from sglang.test.ci.ci_register import register_cuda_ci
register_cuda_ci(est_time=20, stage="base-b-kernel-unit", runner_config="1-gpu-large")
DEVICE = "cuda"
DTYPE = torch.bfloat16
MAX_FP8_DIFF = 5e-4
TEST_CASES = [
pytest.param(19, 150, 80, id="misaligned_projection_shape"),
pytest.param(512, 3072, 4096, id="flux2_added_kv_projection_shape"),
]
def _modelopt_fp8_supported() -> bool:
return torch.cuda.is_available() and cutlass_fp8_supported()
def _calc_diff(x: torch.Tensor, y: torch.Tensor) -> float:
x, y = x.double(), y.double()
denominator = (x * x + y * y).sum()
if denominator == 0:
return 0.0
sim = 2 * (x * y).sum() / denominator
return (1 - sim).item()
def _dequantize_fp8_input(qinput: torch.Tensor, x_scale: torch.Tensor) -> torch.Tensor:
return qinput.to(torch.float32) * x_scale.to(torch.float32)
def _dequantize_fp8_weight(
weight: torch.Tensor, weight_scale: torch.Tensor
) -> torch.Tensor:
if weight_scale.ndim == 0 or weight_scale.numel() == 1:
scale = weight_scale.to(torch.float32)
else:
scale = weight_scale.to(torch.float32).reshape(-1, 1).t()
return weight.to(torch.float32) * scale
def _build_layer(
weight_q: torch.Tensor,
weight_scale: torch.Tensor,
input_scale: torch.Tensor,
) -> tuple[torch.nn.Module, ModelOptFp8LinearMethod]:
output_size, input_size = weight_q.shape
method = ModelOptFp8LinearMethod(
ModelOptFp8Config(is_checkpoint_fp8_serialized=True)
)
layer = torch.nn.Module()
method.create_weights(
layer=layer,
input_size_per_partition=input_size,
output_partition_sizes=[output_size],
input_size=input_size,
output_size=output_size,
params_dtype=DTYPE,
weight_loader=lambda *args, **kwargs: None,
)
layer = layer.to(device=DEVICE)
layer.weight.data.copy_(weight_q)
layer.weight_scale.data.copy_(weight_scale.reshape_as(layer.weight_scale))
layer.input_scale.data.copy_(input_scale.reshape_as(layer.input_scale))
method.process_weights_after_loading(layer)
return layer, method
@pytest.mark.skipif(
not _modelopt_fp8_supported(),
reason="Diffusion ModelOpt FP8 scaled mm correctness requires CUDA FP8 support",
)
@pytest.mark.parametrize("m,n,k", TEST_CASES)
def test_checkpoint_processing(m: int, n: int, k: int) -> None:
generator = torch.Generator(device=DEVICE)
generator.manual_seed(20260410 + m + n + k)
weight = torch.randn((n, k), device=DEVICE, dtype=DTYPE, generator=generator)
weight_q, weight_scale = input_to_float8(weight)
input_scale = torch.tensor(1.0, device=DEVICE, dtype=torch.float32)
layer, _ = _build_layer(weight_q, weight_scale, input_scale)
assert tuple(layer.weight.shape) == (k, n)
assert tuple(layer.weight.stride()) == (1, k)
assert layer.weight.dtype == torch.float8_e4m3fn
assert layer.input_scale.ndim == 0
assert tuple(layer.weight_scale.shape) == (n, 1)
expected_weight = weight_q.t().to(torch.float32) * weight_scale.to(torch.float32)
actual_weight = _dequantize_fp8_weight(layer.weight, layer.weight_scale)
torch.testing.assert_close(actual_weight, expected_weight, atol=0.0, rtol=0.0)
@pytest.mark.skipif(
not _modelopt_fp8_supported(),
reason="Diffusion ModelOpt FP8 scaled mm correctness requires CUDA FP8 support",
)
@pytest.mark.parametrize("m,n,k", TEST_CASES)
def test_shape_correctness(m: int, n: int, k: int) -> None:
generator = torch.Generator(device=DEVICE)
generator.manual_seed(20260410 + m + n + k)
x = torch.randn((m, k), device=DEVICE, dtype=DTYPE, generator=generator)
weight = torch.randn((n, k), device=DEVICE, dtype=DTYPE, generator=generator)
weight_q, weight_scale = input_to_float8(weight)
_, input_scale = input_to_float8(x)
layer, method = _build_layer(weight_q, weight_scale, input_scale)
qinput, x_scale = static_quant_fp8(
x.contiguous(),
layer.input_scale,
repeat_scale=method.cutlass_fp8_supported,
)
expected = torch.matmul(
_dequantize_fp8_input(qinput, x_scale),
_dequantize_fp8_weight(layer.weight, layer.weight_scale),
)
actual = method.apply(layer, x)
diff = _calc_diff(actual, expected.to(dtype=DTYPE))
assert diff < MAX_FP8_DIFF, f"{m=}, {n=}, {k=}, {diff=:.6f}"
if __name__ == "__main__":
sys.exit(pytest.main([__file__, "-v", "-s"]))
@@ -0,0 +1,447 @@
import sys
import flashinfer
import pytest
import torch
from sglang.multimodal_gen.runtime.layers.quantization import (
modelopt_quant as diffusion_modelopt_quant,
)
from sglang.multimodal_gen.runtime.layers.quantization.modelopt_quant import (
ModelOptFp4Config,
ModelOptFp4LinearMethod,
)
from sglang.multimodal_gen.runtime.platforms import current_platform
from sglang.srt.layers.quantization.modelopt_quant import pad_nvfp4_weight
from sglang.test.ci.ci_register import register_cuda_ci
# B200-only correctness coverage for diffusion NVFP4 scaled mm.
register_cuda_ci(est_time=15, stage="base-b-kernel-unit", runner_config="4-gpu-b200")
DEVICE = "cuda"
DTYPE = torch.bfloat16
BLOCK_SIZE = 16
FLOAT4_E2M1_MAX = 6.0
FLOAT8_E4M3_MAX = torch.finfo(torch.float8_e4m3fn).max
FP4_VALUE_LUT = (0.0, 0.5, 1.0, 1.5, 2.0, 3.0, 4.0, 6.0)
DEEPGEMM_FP4_MAX_DIFF = 0.02
TEST_CASES = [
pytest.param(19, 150, 80, id="padding_regression"),
pytest.param(512, 6144, 128, id="flux2_projection_shape"),
]
FLUX2_PROJECTION_SHAPE = (512, 6144, 128)
def _nvfp4_supported() -> bool:
return torch.cuda.is_available() and torch.cuda.get_device_capability() >= (10, 0)
def _make_global_scale(x: torch.Tensor) -> torch.Tensor:
max_abs = torch.amax(x.abs()).clamp_min_(1e-6)
return (FLOAT8_E4M3_MAX * FLOAT4_E2M1_MAX / max_abs).to(torch.float32)
def _calc_diff(x: torch.Tensor, y: torch.Tensor) -> float:
x, y = x.double(), y.double()
denominator = (x * x + y * y).sum()
if denominator == 0:
return 0.0
sim = 2 * (x * y).sum() / denominator
return (1 - sim).item()
def _swap_fp4_nibbles(packed: torch.Tensor) -> torch.Tensor:
return ((packed >> 4) | (packed << 4)).contiguous()
def _fp4_lut(device: torch.device) -> torch.Tensor:
return torch.tensor(FP4_VALUE_LUT, dtype=torch.float32, device=device)
def _unpack_fp4_bytes(packed: torch.Tensor) -> torch.Tensor:
assert packed.dtype == torch.uint8
lut = _fp4_lut(packed.device)
def _decode(nibbles: torch.Tensor) -> torch.Tensor:
values = lut[(nibbles & 0x7).to(torch.long)]
return torch.where((nibbles & 0x8) != 0, -values, values)
low = _decode(packed & 0x0F)
high = _decode((packed & 0xF0) >> 4)
return torch.stack((low, high), dim=-1).reshape(
packed.shape[0], packed.shape[1] * 2
)
def _swizzled_to_linear(
scales_swizzled: torch.Tensor,
rows: int,
cols: int,
) -> torch.Tensor:
scales_swizzled = scales_swizzled.view(torch.float8_e4m3fn)
row_tiles = (rows + 128 - 1) // 128
tile_cols = BLOCK_SIZE * 4
col_tiles = (cols + tile_cols - 1) // tile_cols
tmp = scales_swizzled.reshape(1, row_tiles, col_tiles, 32, 4, 4)
tmp = tmp.permute(0, 1, 4, 3, 2, 5)
linear = tmp.reshape(row_tiles * 128, col_tiles * tile_cols // BLOCK_SIZE)
return linear[:rows, : cols // BLOCK_SIZE]
def _dequantize_nvfp4(
packed: torch.Tensor,
scales_swizzled: torch.Tensor,
global_scale: torch.Tensor,
) -> torch.Tensor:
rows, packed_cols = packed.shape
cols = packed_cols * 2
unpacked = _unpack_fp4_bytes(packed).reshape(rows, cols // BLOCK_SIZE, BLOCK_SIZE)
scales_linear = _swizzled_to_linear(scales_swizzled, rows, cols).to(torch.float32)
return (unpacked * (scales_linear / global_scale).unsqueeze(-1)).reshape(rows, cols)
def _quantize_weight_for_checkpoint(
weight: torch.Tensor, weight_global_scale: torch.Tensor
) -> tuple[torch.Tensor, torch.Tensor]:
weight_fp4, weight_scale_linear = flashinfer.fp4_quantize(
weight,
weight_global_scale,
is_sf_swizzled_layout=False,
)
if weight_scale_linear.dtype == torch.uint8:
weight_scale_linear = weight_scale_linear.view(torch.float8_e4m3fn)
return weight_fp4, weight_scale_linear.contiguous()
def _set_diffusion_fp4_backend(
monkeypatch: pytest.MonkeyPatch, backend: str | None
) -> None:
if backend is None:
monkeypatch.delenv(
"SGLANG_DIFFUSION_FLASHINFER_FP4_GEMM_BACKEND", raising=False
)
else:
monkeypatch.setenv("SGLANG_DIFFUSION_FLASHINFER_FP4_GEMM_BACKEND", backend)
current_platform.__class__.get_modelopt_flashinfer_fp4_backend.cache_clear()
current_platform.__class__.get_modelopt_fp4_gemm_op.cache_clear()
diffusion_modelopt_quant._get_fp4_gemm_op.cache_clear()
def _build_layer(
weight_fp4: torch.Tensor,
weight_scale_linear: torch.Tensor,
input_global_scale: torch.Tensor,
weight_global_scale: torch.Tensor,
*,
weight_scale_device: torch.device | str | None = None,
checkpoint_weight_scale_layout: str = "linear",
) -> tuple[ModelOptFp4LinearMethod, torch.nn.Module]:
output_size, input_size_half = weight_fp4.shape
input_size = input_size_half * 2
method = ModelOptFp4LinearMethod(
ModelOptFp4Config(
is_checkpoint_nvfp4_serialized=True,
group_size=BLOCK_SIZE,
swap_weight_nibbles=True,
checkpoint_weight_scale_layout=checkpoint_weight_scale_layout,
)
)
layer = torch.nn.Module()
method.create_weights(
layer,
input_size_per_partition=input_size,
output_partition_sizes=[output_size],
input_size=input_size,
output_size=output_size,
params_dtype=DTYPE,
weight_loader=lambda *args, **kwargs: None,
)
layer = layer.to(device=DEVICE)
checkpoint_weight = _swap_fp4_nibbles(weight_fp4)
layer.weight.data.copy_(checkpoint_weight)
layer.input_scale.data.copy_(
(1.0 / input_global_scale).reshape_as(layer.input_scale)
)
layer.weight_scale_2.data.copy_(
(1.0 / weight_global_scale).reshape_as(layer.weight_scale_2)
)
layer.weight_scale.data.copy_(weight_scale_linear)
if weight_scale_device is not None:
layer.weight_scale = torch.nn.Parameter(
layer.weight_scale.detach().to(weight_scale_device), requires_grad=False
)
method.process_weights_after_loading(layer)
_, flashinfer_backend = current_platform.get_modelopt_fp4_gemm_op()
if flashinfer_backend == "trtllm":
expected_weight, _ = pad_nvfp4_weight(
weight_fp4, n_alignment=128, k_alignment=0
)
expected_scale = (
_swizzled_to_linear(weight_scale_linear, output_size, input_size)
if checkpoint_weight_scale_layout == "swizzled"
else weight_scale_linear
)
if expected_scale.shape[0] != expected_weight.shape[0]:
pad_n = expected_weight.shape[0] - expected_scale.shape[0]
expected_scale = torch.nn.functional.pad(expected_scale, (0, 0, 0, pad_n))
expected_padding_cols = 0
if expected_scale.shape[1] % 4 != 0:
padded_scale_k = ((expected_scale.shape[1] + 4 - 1) // 4) * 4
pad_scale_k = padded_scale_k - expected_scale.shape[1]
expected_scale = torch.nn.functional.pad(
expected_scale, (0, pad_scale_k, 0, 0)
)
pad_weight_k = pad_scale_k * 8
expected_weight = torch.nn.functional.pad(
expected_weight, (0, pad_weight_k, 0, 0)
)
expected_padding_cols = pad_weight_k
expected_weight = flashinfer.shuffle_matrix_a(
expected_weight.view(torch.uint8), 128
)
expected_scale = (
flashinfer.shuffle_matrix_sf_a(expected_scale.view(torch.uint8), 128)
.reshape(expected_scale.shape)
.view(torch.float8_e4m3fn)
)
assert torch.equal(layer.weight, expected_weight)
assert torch.equal(
layer.weight_scale_interleaved.view(torch.uint8),
expected_scale.view(torch.uint8),
)
assert layer.weights_padding_cols == expected_padding_cols
else:
expected_weight, expected_padding_cols = pad_nvfp4_weight(weight_fp4)
expected_scale_shape = (
((output_size + 128 - 1) // 128) * 128,
(((input_size // BLOCK_SIZE) + 4 - 1) // 4) * 4,
)
assert torch.equal(layer.weight, expected_weight)
assert layer.weight_scale_interleaved.shape == expected_scale_shape
assert layer.weight_scale_interleaved.dtype == torch.float8_e4m3fn
assert layer.weights_padding_cols == expected_padding_cols
torch.testing.assert_close(
layer.alpha,
(1.0 / (input_global_scale * weight_global_scale)).to(torch.float32),
)
torch.testing.assert_close(
layer.input_scale_inv,
input_global_scale.to(torch.float32),
)
return method, layer
def _resolve_mode(mode: str):
if mode == "flashinfer2":
return flashinfer.fp4_quantize, flashinfer.mm_fp4, "cudnn"
if mode == "flashinfer_trtllm":
return flashinfer.fp4_quantize, flashinfer.mm_fp4, "trtllm"
raise ValueError(f"Unknown mode: {mode}")
@pytest.mark.skipif(
not _nvfp4_supported(),
reason="Diffusion NVFP4 scaled mm correctness requires Blackwell GPUs",
)
@pytest.mark.parametrize(
"backend", [None, "flashinfer_trtllm"], ids=["default", "flashinfer_trtllm"]
)
@pytest.mark.parametrize("m,n,k", TEST_CASES)
def test_checkpoint_processing(
monkeypatch: pytest.MonkeyPatch, backend: str | None, m: int, n: int, k: int
) -> None:
_set_diffusion_fp4_backend(monkeypatch, backend)
generator = torch.Generator(device=DEVICE)
generator.manual_seed(20260404 + m + n + k)
weight = torch.randn((n, k), device=DEVICE, dtype=DTYPE, generator=generator)
input_global_scale = torch.tensor(512.0, device=DEVICE, dtype=torch.float32)
weight_global_scale = _make_global_scale(weight)
weight_fp4, weight_scale_linear = _quantize_weight_for_checkpoint(
weight, weight_global_scale
)
_build_layer(
weight_fp4, weight_scale_linear, input_global_scale, weight_global_scale
)
@pytest.mark.skipif(
not _nvfp4_supported(),
reason="Diffusion NVFP4 scaled mm correctness requires Blackwell GPUs",
)
@pytest.mark.parametrize("mode", ["flashinfer2"])
def test_flux2_shape_correctness(mode: str) -> None:
m, n, k = FLUX2_PROJECTION_SHAPE
quantize_op, gemm_op, gemm_backend = _resolve_mode(mode)
generator = torch.Generator(device=DEVICE)
generator.manual_seed(20260404 + m + n + k)
x = torch.randn((m, k), device=DEVICE, dtype=DTYPE, generator=generator)
weight = torch.randn((n, k), device=DEVICE, dtype=DTYPE, generator=generator)
input_global_scale = _make_global_scale(x)
weight_global_scale = _make_global_scale(weight)
alpha = (1.0 / (input_global_scale * weight_global_scale)).to(torch.float32)
x_fp4, x_scale_swizzled = quantize_op(x, input_global_scale)
weight_fp4, weight_scale_swizzled = quantize_op(weight, weight_global_scale)
if x_scale_swizzled.dtype == torch.uint8:
x_scale_swizzled = x_scale_swizzled.view(torch.float8_e4m3fn)
if weight_scale_swizzled.dtype == torch.uint8:
weight_scale_swizzled = weight_scale_swizzled.view(torch.float8_e4m3fn)
expected = torch.matmul(
_dequantize_nvfp4(x_fp4, x_scale_swizzled, input_global_scale),
_dequantize_nvfp4(weight_fp4, weight_scale_swizzled, weight_global_scale).t(),
)
actual = gemm_op(
x_fp4,
weight_fp4.t(),
x_scale_swizzled,
weight_scale_swizzled.t(),
alpha,
DTYPE,
backend=gemm_backend,
)
diff = _calc_diff(actual, expected.to(dtype=DTYPE))
assert diff < DEEPGEMM_FP4_MAX_DIFF, f"{mode=}, {m=}, {n=}, {k=}, {diff=:.6f}"
@pytest.mark.skipif(
not _nvfp4_supported(),
reason="Diffusion NVFP4 scaled mm correctness requires Blackwell GPUs",
)
def test_flux2_shape_correctness_flashinfer_trtllm(
monkeypatch: pytest.MonkeyPatch,
) -> None:
_set_diffusion_fp4_backend(monkeypatch, "flashinfer_trtllm")
m, n, k = FLUX2_PROJECTION_SHAPE
generator = torch.Generator(device=DEVICE)
generator.manual_seed(20260404 + m + n + k + 17)
x = torch.randn((m, k), device=DEVICE, dtype=DTYPE, generator=generator)
weight = torch.randn((n, k), device=DEVICE, dtype=DTYPE, generator=generator)
input_global_scale = _make_global_scale(x)
weight_global_scale = _make_global_scale(weight)
weight_fp4, weight_scale_linear = _quantize_weight_for_checkpoint(
weight, weight_global_scale
)
method, layer = _build_layer(
weight_fp4, weight_scale_linear, input_global_scale, weight_global_scale
)
actual = method.apply(layer, x)
x_fp4, x_scale_swizzled = flashinfer.fp4_quantize(x, input_global_scale)
weight_fp4_ref, weight_scale_swizzled = flashinfer.fp4_quantize(
weight, weight_global_scale
)
if x_scale_swizzled.dtype == torch.uint8:
x_scale_swizzled = x_scale_swizzled.view(torch.float8_e4m3fn)
if weight_scale_swizzled.dtype == torch.uint8:
weight_scale_swizzled = weight_scale_swizzled.view(torch.float8_e4m3fn)
expected = torch.matmul(
_dequantize_nvfp4(x_fp4, x_scale_swizzled, input_global_scale),
_dequantize_nvfp4(
weight_fp4_ref, weight_scale_swizzled, weight_global_scale
).t(),
)
diff = _calc_diff(actual, expected.to(dtype=DTYPE))
assert diff < DEEPGEMM_FP4_MAX_DIFF, f"{m=}, {n=}, {k=}, {diff=:.6f}"
@pytest.mark.skipif(
not _nvfp4_supported(),
reason="Diffusion NVFP4 scaled mm correctness requires Blackwell GPUs",
)
def test_flux2_swizzled_scale_checkpoint_flashinfer_trtllm_matches_cudnn(
monkeypatch: pytest.MonkeyPatch,
) -> None:
_set_diffusion_fp4_backend(monkeypatch, "flashinfer_trtllm")
m, n, k = FLUX2_PROJECTION_SHAPE
generator = torch.Generator(device=DEVICE)
generator.manual_seed(20260517 + m + n + k)
x = torch.randn((m, k), device=DEVICE, dtype=DTYPE, generator=generator)
weight = torch.randn((n, k), device=DEVICE, dtype=DTYPE, generator=generator)
input_global_scale = _make_global_scale(x)
weight_global_scale = _make_global_scale(weight)
alpha = (1.0 / (input_global_scale * weight_global_scale)).to(torch.float32)
x_fp4, x_scale_swizzled = flashinfer.fp4_quantize(x, input_global_scale)
weight_fp4, weight_scale_swizzled = flashinfer.fp4_quantize(
weight, weight_global_scale
)
if x_scale_swizzled.dtype == torch.uint8:
x_scale_swizzled = x_scale_swizzled.view(torch.float8_e4m3fn)
if weight_scale_swizzled.dtype == torch.uint8:
weight_scale_swizzled = weight_scale_swizzled.view(torch.float8_e4m3fn)
method, layer = _build_layer(
weight_fp4,
weight_scale_swizzled,
input_global_scale,
weight_global_scale,
checkpoint_weight_scale_layout="swizzled",
)
actual = method.apply(layer, x)
expected = flashinfer.mm_fp4(
x_fp4,
weight_fp4.t(),
x_scale_swizzled,
weight_scale_swizzled.t(),
alpha,
DTYPE,
backend="cudnn",
)
diff = _calc_diff(actual, expected)
assert diff < DEEPGEMM_FP4_MAX_DIFF, f"{m=}, {n=}, {k=}, {diff=:.6f}"
@pytest.mark.skipif(
not _nvfp4_supported(),
reason="Diffusion NVFP4 scaled mm correctness requires Blackwell GPUs",
)
def test_checkpoint_processing_flashinfer_trtllm_cpu_weight_scale(
monkeypatch: pytest.MonkeyPatch,
) -> None:
_set_diffusion_fp4_backend(monkeypatch, "flashinfer_trtllm")
m, n, k = FLUX2_PROJECTION_SHAPE
generator = torch.Generator(device=DEVICE)
generator.manual_seed(20260413 + m + n + k)
weight = torch.randn((n, k), device=DEVICE, dtype=DTYPE, generator=generator)
input_global_scale = torch.tensor(512.0, device=DEVICE, dtype=torch.float32)
weight_global_scale = _make_global_scale(weight)
weight_fp4, weight_scale_linear = _quantize_weight_for_checkpoint(
weight, weight_global_scale
)
_build_layer(
weight_fp4,
weight_scale_linear,
input_global_scale,
weight_global_scale,
weight_scale_device="cpu",
)
if __name__ == "__main__":
sys.exit(pytest.main([__file__, "-v", "-s"]))