[MoE Refactor] Centralize FlashInfer CUTLASS MoE runner (#28211)

This commit is contained in:
Mohammad Miadh Angkad
2026-06-25 13:40:33 -07:00
committed by GitHub
parent dbe9e3b706
commit 212c30d008
8 changed files with 457 additions and 388 deletions
@@ -0,0 +1,372 @@
"""FlashInfer CUTLASS MoE fused funcs.
This module owns the FlashInfer ``cutlass_fused_moe`` calls used by the
unquantized, ModelOpt FP8, ModelOpt NVFP4, and SM90 MXFP4 MoE paths.
Quantization methods prepare a small quant_info payload and route through
``MoeRunner``.
"""
from __future__ import annotations
from dataclasses import dataclass
from typing import TYPE_CHECKING, Optional
import torch
from sglang.srt.distributed import get_tp_group
from sglang.srt.distributed.device_communicators.pynccl_allocator import (
use_symmetric_memory,
)
from sglang.srt.layers.dp_attention import is_allocation_symmetric
from sglang.srt.layers.moe.moe_runner.base import (
MoeQuantInfo,
MoeRunnerConfig,
register_fused_func,
)
from sglang.srt.layers.quantization.fp8_kernel import scaled_fp8_quant
from sglang.srt.utils import is_flashinfer_available
from sglang.srt.utils.common import next_power_of_2
if TYPE_CHECKING:
from sglang.srt.layers.moe.token_dispatcher.flashinfer import (
FlashinferCombineInput,
FlashinferDispatchOutput,
)
from sglang.srt.layers.moe.token_dispatcher.standard import (
StandardCombineInput,
StandardDispatchOutput,
)
@dataclass
class FlashInferCutlassMoeQuantInfo(MoeQuantInfo):
"""Payload for FlashInfer CUTLASS fused MoE.
``quant_type`` selects the input/weight conventions:
- ``"bf16"``: unquantized weights, BF16/FP16 input, no quant scales.
- ``"fp8"``: FP8 weights, FP8-quantized input, per-tensor scales.
- ``"fp4"``: NVFP4 packed weights and optional NVFP4 packed input.
"""
quant_type: str
w13_weight: torch.Tensor
w2_weight: torch.Tensor
quant_scales: Optional[list[torch.Tensor]] = None
output_dtype: Optional[torch.dtype] = None
moe_tp_size: int = 1
moe_tp_rank: int = 0
moe_ep_size: int = 1
moe_ep_rank: int = 0
apply_routed_scaling_factor: bool = True
@dataclass
class FlashInferCutlassMxfp4MoeQuantInfo(MoeQuantInfo):
"""Quantization payload for the SM90 CUTLASS W4A16 MXFP4 MoE path.
Weights and scales are pre-interleaved at load time via
``interleave_moe_{weights,scales}_for_sm90_mixed_gemm``; this dataclass
only carries references plus the per-call routing/topology fields.
"""
# Pre-interleaved weights (uint8, packed FP4)
w13_weight: torch.Tensor # [E, 2*N, K/2]
w2_weight: torch.Tensor # [E, K, N/2]
# Pre-interleaved E8M0 block scales (uint8; viewed as int32 at call time)
w13_weight_scale: torch.Tensor # [E, 2*N, K/32]
w2_weight_scale: torch.Tensor # [E, K, N/32]
# Per-expert bias. GPT-OSS has both; DSv4 leaves both None.
w13_bias: Optional[torch.Tensor] = None # bf16 [E, 2*N]
w2_bias: Optional[torch.Tensor] = None # bf16 [E, K]
# Per-expert SwiGLU scalars (fp32 [E]). Either all three are present
# (clamped SwiGLU) or all three are None (kernel default SwiGLU).
swiglu_alpha: Optional[torch.Tensor] = None
swiglu_beta: Optional[torch.Tensor] = None
swiglu_limit: Optional[torch.Tensor] = None
# TP/EP topology (forwarded to the FlashInfer kernel)
moe_tp_size: int = 1
moe_tp_rank: int = 0
moe_ep_size: int = 1
moe_ep_rank: int = 0
# GPT-OSS pads its input hidden dim up to the (pre-padded) loaded weight
# width and trims the output back. DSv4 leaves this as ``None`` (no pad).
padded_hidden: Optional[int] = None
def _flashinfer_cutlass_fused_moe():
if not is_flashinfer_available():
raise RuntimeError(
"flashinfer_cutlass MoE runner backend requires flashinfer to be installed."
)
from flashinfer.fused_moe import cutlass_fused_moe
from flashinfer.fused_moe.core import ActivationType
return cutlass_fused_moe, ActivationType
def _activation_type(runner_config: MoeRunnerConfig):
from sglang.srt.layers.moe.moe_runner.flashinfer_trtllm import get_activation_type
_, ActivationType = _flashinfer_cutlass_fused_moe()
activation = ActivationType(
get_activation_type(
runner_config.activation,
is_gated=runner_config.is_gated,
)
)
supported = {
ActivationType.Swiglu,
ActivationType.Geglu,
ActivationType.Relu2,
ActivationType.Identity,
}
assert activation in supported, (
f"Activation {runner_config.activation!r} "
f"(is_gated={runner_config.is_gated}) maps to {activation.name}, "
"which is not supported by flashinfer cutlass moe."
)
return activation
def _maybe_apply_routed_scaling_factor(
output: torch.Tensor,
quant_info: FlashInferCutlassMoeQuantInfo,
runner_config: MoeRunnerConfig,
) -> torch.Tensor:
if (
quant_info.apply_routed_scaling_factor
and runner_config.routed_scaling_factor is not None
):
output.mul_(runner_config.routed_scaling_factor)
return output
def _prepare_input(
dispatch_output,
quant_info: FlashInferCutlassMoeQuantInfo,
runner_config: MoeRunnerConfig,
) -> tuple[torch.Tensor, Optional[torch.Tensor], torch.dtype, int]:
x = dispatch_output.hidden_states
x_sf = dispatch_output.hidden_states_scale
if quant_info.quant_type == "fp8":
assert quant_info.quant_scales is not None and len(quant_info.quant_scales) == 4
x, _ = scaled_fp8_quant(x, quant_info.quant_scales[3])
x_sf = None
output_dtype = quant_info.output_dtype or dispatch_output.hidden_states.dtype
output_col = dispatch_output.hidden_states.shape[1]
elif quant_info.quant_type == "fp4":
output_dtype = quant_info.output_dtype or torch.bfloat16
output_col = x.shape[1]
if x_sf is not None and runner_config.is_gated:
output_col *= 2
else:
assert quant_info.quant_type == "bf16"
output_dtype = quant_info.output_dtype or x.dtype
output_col = x.shape[1]
return x, x_sf, output_dtype, output_col
def _run_flashinfer_cutlass(
*,
dispatch_output,
quant_info: FlashInferCutlassMoeQuantInfo,
runner_config: MoeRunnerConfig,
output: Optional[torch.Tensor] = None,
enable_alltoall: bool = False,
) -> torch.Tensor:
flashinfer_cutlass_fused_moe, _ = _flashinfer_cutlass_fused_moe()
topk_output = dispatch_output.topk_output
topk_weights = topk_output.topk_weights
topk_ids = topk_output.topk_ids
x, x_sf, output_dtype, output_col = _prepare_input(
dispatch_output, quant_info, runner_config
)
if output is None:
with use_symmetric_memory(
get_tp_group(), disabled=not is_allocation_symmetric()
):
output = torch.empty(
x.shape[0],
output_col,
dtype=output_dtype,
device=x.device,
)
w13_weight = quant_info.w13_weight
w2_weight = quant_info.w2_weight
quant_scales = quant_info.quant_scales
if quant_info.quant_type == "fp4":
w13_weight = w13_weight.view(torch.long)
w2_weight = w2_weight.view(torch.long)
assert quant_scales is not None and len(quant_scales) == 6
quant_scales = [
quant_scales[0],
quant_scales[1].view(torch.int32),
quant_scales[2],
quant_scales[3],
quant_scales[4].view(torch.int32),
quant_scales[5],
]
output = flashinfer_cutlass_fused_moe(
output=output,
input=x,
token_selected_experts=topk_ids.to(torch.int),
token_final_scales=topk_weights,
fc1_expert_weights=w13_weight,
fc2_expert_weights=w2_weight,
output_dtype=output_dtype,
input_sf=x_sf,
quant_scales=quant_scales,
ep_size=quant_info.moe_ep_size,
ep_rank=quant_info.moe_ep_rank,
tp_size=quant_info.moe_tp_size,
tp_rank=quant_info.moe_tp_rank,
tune_max_num_tokens=next_power_of_2(x.shape[0]),
activation_type=_activation_type(runner_config),
enable_alltoall=enable_alltoall,
)[0]
if quant_info.quant_type in ("bf16", "fp8"):
_maybe_apply_routed_scaling_factor(output, quant_info, runner_config)
return output
@register_fused_func("none", "flashinfer_cutlass")
def fused_experts_none_to_flashinfer_cutlass(
dispatch_output: StandardDispatchOutput,
quant_info: MoeQuantInfo,
runner_config: MoeRunnerConfig,
) -> StandardCombineInput:
from sglang.srt.layers.moe.token_dispatcher.standard import StandardCombineInput
assert isinstance(
quant_info, FlashInferCutlassMoeQuantInfo
), f"Unexpected quant_info type for flashinfer_cutlass: {type(quant_info)}"
assert (
not runner_config.apply_router_weight_on_input
), "apply_router_weight_on_input is not supported for FlashInfer CUTLASS"
output = _run_flashinfer_cutlass(
dispatch_output=dispatch_output,
quant_info=quant_info,
runner_config=runner_config,
)
return StandardCombineInput(hidden_states=output)
@register_fused_func("flashinfer", "flashinfer_cutlass")
def fused_experts_flashinfer_to_flashinfer_cutlass(
dispatch_output: FlashinferDispatchOutput,
quant_info: MoeQuantInfo,
runner_config: MoeRunnerConfig,
) -> FlashinferCombineInput:
from sglang.srt.layers.moe.token_dispatcher.flashinfer import (
FlashinferCombineInput,
)
assert isinstance(
quant_info, FlashInferCutlassMoeQuantInfo
), f"Unexpected quant_info type for flashinfer_cutlass: {type(quant_info)}"
assert (
not runner_config.apply_router_weight_on_input
), "apply_router_weight_on_input is not supported for FlashInfer CUTLASS"
output = _run_flashinfer_cutlass(
dispatch_output=dispatch_output,
quant_info=quant_info,
runner_config=runner_config,
output=dispatch_output.moe_output,
enable_alltoall=True,
)
return FlashinferCombineInput(hidden_states=output)
@register_fused_func("none", "flashinfer_mxfp4")
def fused_experts_none_to_flashinfer_mxfp4(
dispatch_output: StandardDispatchOutput,
quant_info: MoeQuantInfo,
runner_config: MoeRunnerConfig,
) -> StandardCombineInput:
"""SM90 W4A16 MXFP4 fused expert forward pass.
This preserves the ``flashinfer_mxfp4`` runner backend registration while
centralizing the CUTLASS execution in this module.
"""
from sglang.srt.layers.moe.token_dispatcher.standard import StandardCombineInput
from sglang.srt.layers.moe.topk import TopKOutputChecker
assert isinstance(
quant_info, FlashInferCutlassMxfp4MoeQuantInfo
), f"Unexpected quant_info type for flashinfer_mxfp4: {type(quant_info)}"
flashinfer_cutlass_fused_moe, ActivationType = _flashinfer_cutlass_fused_moe()
x = dispatch_output.hidden_states
topk_output = dispatch_output.topk_output
# Under ``--moe-runner-backend flashinfer_mxfp4`` topk may be in bypassed
# form (the SM100 trtllm-gen path does routing internally). The CUTLASS
# SM90 path needs explicit topk_ids / topk_weights; materialize here.
if TopKOutputChecker.format_is_bypassed(topk_output):
topk_output = topk_output.to_standard()
topk_ids = topk_output.topk_ids
topk_weights = topk_output.topk_weights
# GPT-OSS: pad input hidden dim up to the loaded weight width. DSv4
# leaves padded_hidden as None (or equal to origin_hidden), no pad.
origin_hidden = x.shape[-1]
padded_hidden = quant_info.padded_hidden
do_pad = padded_hidden is not None and padded_hidden != origin_hidden
if do_pad:
x = torch.nn.functional.pad(
x,
(0, padded_hidden - origin_hidden),
mode="constant",
value=0.0,
)
out_hidden = padded_hidden if do_pad else origin_hidden
output_dtype = torch.bfloat16
with use_symmetric_memory(get_tp_group(), disabled=not is_allocation_symmetric()):
out = torch.empty(x.shape[0], out_hidden, dtype=output_dtype, device=x.device)
flashinfer_cutlass_fused_moe(
input=x,
token_selected_experts=topk_ids.to(torch.int),
token_final_scales=topk_weights,
fc1_expert_weights=quant_info.w13_weight,
fc2_expert_weights=quant_info.w2_weight,
output_dtype=output_dtype,
quant_scales=[
quant_info.w13_weight_scale.view(torch.int32),
quant_info.w2_weight_scale.view(torch.int32),
],
fc1_expert_biases=quant_info.w13_bias,
fc2_expert_biases=quant_info.w2_bias,
swiglu_alpha=quant_info.swiglu_alpha,
swiglu_beta=quant_info.swiglu_beta,
swiglu_limit=quant_info.swiglu_limit,
tp_size=quant_info.moe_tp_size,
tp_rank=quant_info.moe_tp_rank,
ep_size=quant_info.moe_ep_size,
ep_rank=quant_info.moe_ep_rank,
use_w4_group_scaling=True,
activation_type=ActivationType.Swiglu,
tune_max_num_tokens=next_power_of_2(x.shape[0]),
output=out,
)
if do_pad:
out = out[:, :origin_hidden].contiguous()
return StandardCombineInput(hidden_states=out)
@@ -1,174 +0,0 @@
"""FlashInfer SM90 cutlass mixed-input W4A16 MXFP4 MoE fused func.
Registered for ``("none", "flashinfer_mxfp4")``. Drives FlashInfer's
``cutlass_fused_moe(use_w4_group_scaling=True)`` (PR #3084 in flashinfer,
SM90 only). Quant methods build the quant_info each forward and call
``MoeRunner.run(dispatch_output, quant_info)``.
Two production call sites share this fused func:
- GPT-OSS via :class:`Mxfp4MoEMethod` (input pad/output trim + per-expert
SwiGLU scalars + per-expert bias)
- DSv4 via :class:`Mxfp4FlashinferCutlassMoEMethod` (no bias, optional
SwiGLU scalars, no padding)
The SM100 trtllm-gen path also lives under ``MoeRunnerBackend.FLASHINFER_MXFP4``
but is intentionally left in the legacy bypass path for now; migrating it is a
follow-up.
"""
from __future__ import annotations
from dataclasses import dataclass
from typing import TYPE_CHECKING, Optional
import torch
from sglang.srt.distributed import get_tp_group
from sglang.srt.distributed.device_communicators.pynccl_allocator import (
use_symmetric_memory,
)
from sglang.srt.layers.dp_attention import is_allocation_symmetric
from sglang.srt.layers.moe.moe_runner.base import (
MoeQuantInfo,
MoeRunnerConfig,
register_fused_func,
)
from sglang.srt.utils import is_flashinfer_available
from sglang.srt.utils.common import next_power_of_2
if TYPE_CHECKING:
from sglang.srt.layers.moe.token_dispatcher import StandardDispatchOutput
from sglang.srt.layers.moe.token_dispatcher.standard import StandardCombineInput
@dataclass
class FlashInferMxfp4CutlassMoeQuantInfo(MoeQuantInfo):
"""Quantization payload for the SM90 cutlass W4A16 MXFP4 MoE path.
Weights and scales are pre-interleaved at load time via
``interleave_moe_{weights,scales}_for_sm90_mixed_gemm``; this dataclass
only carries references plus the per-call routing/topology fields.
"""
# Pre-interleaved weights (uint8, packed FP4)
w13_weight: torch.Tensor # [E, 2*N, K/2]
w2_weight: torch.Tensor # [E, K, N/2]
# Pre-interleaved E8M0 block scales (uint8; viewed as int32 at call time)
w13_weight_scale: torch.Tensor # [E, 2*N, K/32]
w2_weight_scale: torch.Tensor # [E, K, N/32]
# Per-expert bias. GPT-OSS has both; DSv4 leaves both None.
w13_bias: Optional[torch.Tensor] = None # bf16 [E, 2*N]
w2_bias: Optional[torch.Tensor] = None # bf16 [E, K]
# Per-expert SwiGLU scalars (fp32 [E]). Either all three are present
# (clamped SwiGLU) or all three are None (kernel default SwiGLU).
swiglu_alpha: Optional[torch.Tensor] = None
swiglu_beta: Optional[torch.Tensor] = None
swiglu_limit: Optional[torch.Tensor] = None
# TP/EP topology (forwarded to the FlashInfer kernel)
moe_tp_size: int = 1
moe_tp_rank: int = 0
moe_ep_size: int = 1
moe_ep_rank: int = 0
# GPT-OSS pads its input hidden dim up to the (pre-padded) loaded weight
# width and trims the output back. DSv4 leaves this as ``None`` (no pad).
padded_hidden: Optional[int] = None
def _flashinfer_cutlass_fused_moe():
"""Lazy import — keeps non-flashinfer wheels importable."""
if not is_flashinfer_available():
raise RuntimeError(
"flashinfer_mxfp4 runner backend requires flashinfer to be installed."
)
from flashinfer.fused_moe import cutlass_fused_moe
from flashinfer.fused_moe.core import ActivationType
return cutlass_fused_moe, ActivationType
@register_fused_func("none", "flashinfer_mxfp4")
def fused_experts_none_to_flashinfer_mxfp4(
dispatch_output: StandardDispatchOutput,
quant_info: MoeQuantInfo,
runner_config: MoeRunnerConfig,
) -> StandardCombineInput:
"""SM90 W4A16 MXFP4 fused expert forward pass.
Mirrors the legacy ``Mxfp4MoEMethod._apply_sm90_cutlass`` and DSv4's
``Mxfp4FlashinferCutlassMoEMethod.apply`` exactly; difference vs those is
that all per-layer state arrives via ``quant_info`` rather than via the
layer module, so this function is layer-agnostic.
"""
from sglang.srt.layers.moe.token_dispatcher.standard import StandardCombineInput
from sglang.srt.layers.moe.topk import TopKOutputChecker
assert isinstance(
quant_info, FlashInferMxfp4CutlassMoeQuantInfo
), f"Unexpected quant_info type for flashinfer_mxfp4: {type(quant_info)}"
flashinfer_cutlass_fused_moe, ActivationType = _flashinfer_cutlass_fused_moe()
x = dispatch_output.hidden_states
topk_output = dispatch_output.topk_output
# Under ``--moe-runner-backend flashinfer_mxfp4`` topk may be in bypassed
# form (the SM100 trtllm-gen path does routing internally). The cutlass
# SM90 path needs explicit topk_ids / topk_weights; materialize here.
if TopKOutputChecker.format_is_bypassed(topk_output):
topk_output = topk_output.to_standard()
topk_ids = topk_output.topk_ids
topk_weights = topk_output.topk_weights
# GPT-OSS: pad input hidden dim up to the loaded weight width. DSv4
# leaves padded_hidden as None (or equal to origin_hidden), no pad.
origin_hidden = x.shape[-1]
padded_hidden = quant_info.padded_hidden
do_pad = padded_hidden is not None and padded_hidden != origin_hidden
if do_pad:
x = torch.nn.functional.pad(
x,
(0, padded_hidden - origin_hidden),
mode="constant",
value=0.0,
)
out_hidden = padded_hidden if do_pad else origin_hidden
output_dtype = torch.bfloat16
with use_symmetric_memory(get_tp_group(), disabled=not is_allocation_symmetric()):
out = torch.empty(x.shape[0], out_hidden, dtype=output_dtype, device=x.device)
flashinfer_cutlass_fused_moe(
input=x,
token_selected_experts=topk_ids.to(torch.int),
token_final_scales=topk_weights,
fc1_expert_weights=quant_info.w13_weight,
fc2_expert_weights=quant_info.w2_weight,
output_dtype=output_dtype,
quant_scales=[
quant_info.w13_weight_scale.view(torch.int32),
quant_info.w2_weight_scale.view(torch.int32),
],
fc1_expert_biases=quant_info.w13_bias,
fc2_expert_biases=quant_info.w2_bias,
swiglu_alpha=quant_info.swiglu_alpha,
swiglu_beta=quant_info.swiglu_beta,
swiglu_limit=quant_info.swiglu_limit,
tp_size=quant_info.moe_tp_size,
tp_rank=quant_info.moe_tp_rank,
ep_size=quant_info.moe_ep_size,
ep_rank=quant_info.moe_ep_rank,
use_w4_group_scaling=True,
activation_type=ActivationType.Swiglu,
tune_max_num_tokens=next_power_of_2(x.shape[0]),
output=out,
)
if do_pad:
out = out[:, :origin_hidden].contiguous()
return StandardCombineInput(hidden_states=out)
@@ -61,6 +61,8 @@ class MoeRunner:
self.runner_core = None # FlashInfer TRT-LLM only supports fused path
elif runner_backend.is_flashinfer_cutedsl():
self.runner_core = None # FlashInfer CuteDSL only supports fused path
elif runner_backend.is_flashinfer_cutlass():
self.runner_core = None # FlashInfer CUTLASS only supports fused path
elif runner_backend.is_flashinfer_mxfp4():
self.runner_core = None # FlashInfer MXFP4 only supports fused path
else:
@@ -4,24 +4,17 @@
from __future__ import annotations
import logging
from enum import IntEnum
from typing import TYPE_CHECKING, Any, Dict, List, Optional
import regex as re
import torch
from torch.nn.parameter import Parameter
from sglang.srt.distributed import get_tp_group
from sglang.srt.distributed.device_communicators.pynccl_allocator import (
use_symmetric_memory,
)
from sglang.srt.environ import envs
from sglang.srt.layers.dp_attention import is_allocation_symmetric
from sglang.srt.layers.moe import (
MoeRunner,
MoeRunnerBackend,
MoeRunnerConfig,
get_moe_a2a_backend,
get_moe_runner_backend,
)
from sglang.srt.layers.moe.cutlass_moe_params import CutlassMoEParams, CutlassMoEType
@@ -71,7 +64,6 @@ from sglang.srt.utils.common import (
is_flashinfer_available,
is_sm100_supported,
is_sm120_supported,
next_power_of_2,
round_up,
)
from sglang.srt.utils.custom_op import register_custom_op
@@ -104,20 +96,6 @@ if is_cuda():
else:
cutlass_fp4_gemm = None
try:
from flashinfer.fused_moe import cutlass_fused_moe as flashinfer_cutlass_fused_moe
from flashinfer.fused_moe.core import ActivationType
except ImportError:
flashinfer_cutlass_fused_moe = None
# Define a minimal ActivationType enum if flashinfer is not available
class ActivationType(IntEnum):
Swiglu = 3
Geglu = 4
Relu2 = 6
Identity = 7
# Initialize logger for the module
logger = logging.getLogger(__name__)
@@ -1031,7 +1009,15 @@ class ModelOptFp8MoEMethod(FusedMoEMethodBase):
self, layer: torch.nn.Module, moe_runner_config: MoeRunnerConfig
):
self.moe_runner_config = moe_runner_config
self.runner = MoeRunner(MoeRunnerBackend.TRITON, moe_runner_config)
moe_runner_backend = get_moe_runner_backend()
if moe_runner_backend.is_flashinfer_cutlass():
import sglang.srt.layers.moe.moe_runner.flashinfer_cutlass # noqa: F401
self.runner = MoeRunner(
MoeRunnerBackend.FLASHINFER_CUTLASS, moe_runner_config
)
else:
self.runner = MoeRunner(MoeRunnerBackend.TRITON, moe_runner_config)
def apply(
self,
@@ -1040,7 +1026,6 @@ class ModelOptFp8MoEMethod(FusedMoEMethodBase):
) -> CombineInput:
x = dispatch_output.hidden_states
topk_output = dispatch_output.topk_output
from sglang.srt.layers.moe.token_dispatcher import StandardCombineInput
from sglang.srt.layers.moe.topk import TopKOutputChecker
# Fast path: TRT-LLM FP8 per-tensor MoE using BYPASSED TopK routing
@@ -1052,14 +1037,9 @@ class ModelOptFp8MoEMethod(FusedMoEMethodBase):
from sglang.srt.layers.moe.moe_runner.flashinfer_trtllm import (
FlashInferTrtllmFp8MoeQuantInfo,
fused_experts_none_to_flashinfer_trtllm_fp8,
)
from sglang.srt.layers.moe.utils import RoutingMethodType
topk_config = topk_output.topk_config
from sglang.srt.layers.moe.moe_runner.flashinfer_trtllm import (
get_activation_type,
)
from sglang.srt.layers.moe.utils import RoutingMethodType
_SUPPORTED_FP8_ACTIVATIONS = {"silu", "relu2"}
assert self.moe_runner_config.activation in _SUPPORTED_FP8_ACTIVATIONS, (
@@ -1096,75 +1076,33 @@ class ModelOptFp8MoEMethod(FusedMoEMethodBase):
)
if get_moe_runner_backend().is_flashinfer_cutlass():
from sglang.srt.layers.moe.moe_runner.flashinfer_trtllm import (
get_activation_type,
)
activation_str = self.moe_runner_config.activation
assert activation_str in _SUPPORTED_ACT_STRS, (
f"Activation {activation_str!r} is not supported for "
f"flashinfer cutlass fp8 moe (supported: {_SUPPORTED_ACT_STRS})."
)
activation = ActivationType(
get_activation_type(
activation_str, is_gated=self.moe_runner_config.is_gated
)
from sglang.srt.layers.moe.moe_runner.flashinfer_cutlass import (
FlashInferCutlassMoeQuantInfo,
)
# FlashInfer CUTLASS MoE supports gated Swiglu/Geglu and non-gated
# Relu2/Identity. Non-gated Silu/Gelu are not implemented.
_CUTLASS_SUPPORTED = {
ActivationType.Swiglu,
ActivationType.Geglu,
ActivationType.Relu2,
ActivationType.Identity,
}
assert activation in _CUTLASS_SUPPORTED, (
f"Activation {activation_str!r} (is_gated="
f"{self.moe_runner_config.is_gated}) maps to {activation.name}, "
"which is not supported by flashinfer cutlass fp8 moe."
)
topk_weights, topk_ids = topk_output.topk_weights, topk_output.topk_ids
x_fp8, _ = scaled_fp8_quant(x, layer.w13_input_scale)
output_dtype = x.dtype
original_col = x.shape[1]
x_sf = None
with use_symmetric_memory(
get_tp_group(), disabled=not is_allocation_symmetric()
):
symm_output = torch.empty(
x.shape[0], original_col, dtype=output_dtype, device=x.device
)
output = flashinfer_cutlass_fused_moe(
output=symm_output,
input=x_fp8,
token_selected_experts=topk_ids.to(torch.int),
token_final_scales=topk_weights,
fc1_expert_weights=layer.w13_weight,
fc2_expert_weights=layer.w2_weight,
output_dtype=output_dtype,
input_sf=x_sf,
quant_info = FlashInferCutlassMoeQuantInfo(
quant_type="fp8",
w13_weight=layer.w13_weight,
w2_weight=layer.w2_weight,
quant_scales=[
layer.fc1_dequant,
layer.fc2_quant,
layer.fc2_dequant,
layer.fc1_input_dequant,
],
ep_size=layer.moe_ep_size,
ep_rank=layer.moe_ep_rank,
tp_size=layer.moe_tp_size,
tp_rank=layer.moe_tp_rank,
tune_max_num_tokens=next_power_of_2(x.shape[0]),
activation_type=activation,
)[0]
if (
not layer.should_fuse_routed_scaling_factor_in_topk
and self.moe_runner_config.routed_scaling_factor is not None
):
output.mul_(self.moe_runner_config.routed_scaling_factor)
return StandardCombineInput(hidden_states=output)
output_dtype=x.dtype,
moe_ep_size=layer.moe_ep_size,
moe_ep_rank=layer.moe_ep_rank,
moe_tp_size=layer.moe_tp_size,
moe_tp_rank=layer.moe_tp_rank,
apply_routed_scaling_factor=not layer.should_fuse_routed_scaling_factor_in_topk,
)
return self.runner.run(dispatch_output, quant_info)
quant_info = TritonMoeQuantInfo(
w13_weight=layer.w13_weight,
@@ -1320,9 +1258,9 @@ class ModelOptFp4Config(ModelOptQuantConfig):
"Expected either flat format (config.json) or nested format (hf_quant_config.json)."
)
if not quant_method in ["FP8", "NVFP4"]:
if quant_method not in ["FP8", "NVFP4"]:
raise ValueError(
f"ModelOpt currently only supports: FP8, NVFP4"
"ModelOpt currently only supports: FP8, NVFP4"
" quantizations in sglang. Please check the "
"quantization config for your model's configuration."
)
@@ -2327,8 +2265,10 @@ class ModelOptNvFp4FusedMoEMethod(FusedMoEMethodBase):
if moe_runner_backend.is_flashinfer_cutedsl():
import sglang.srt.layers.moe.moe_runner.flashinfer_cutedsl # noqa: F401 triggers @register_fused_func
if not moe_runner_backend.is_flashinfer_cutlass():
self.runner = MoeRunner(moe_runner_backend, moe_runner_config)
if moe_runner_backend.is_flashinfer_cutlass():
import sglang.srt.layers.moe.moe_runner.flashinfer_cutlass # noqa: F401
self.runner = MoeRunner(moe_runner_backend, moe_runner_config)
def apply(
self,
@@ -2458,85 +2398,33 @@ class ModelOptNvFp4FusedMoEMethod(FusedMoEMethodBase):
return self.runner.run(dispatch_output, quant_info)
if self.enable_flashinfer_cutlass_moe:
from sglang.srt.layers.moe.moe_runner.flashinfer_trtllm import (
get_activation_type,
from sglang.srt.layers.moe.moe_runner.flashinfer_cutlass import (
FlashInferCutlassMoeQuantInfo,
)
from sglang.srt.layers.moe.token_dispatcher import DispatchOutputChecker
assert (
not moe_runner_config.apply_router_weight_on_input
), "apply_router_weight_on_input is not supported for Flashinfer"
# Resolve the FlashInfer ActivationType honoring the gated flag,
# then verify the CUTLASS FP4 kernel supports it.
fi_activation = ActivationType(
get_activation_type(activation, is_gated=moe_runner_config.is_gated)
)
_CUTLASS_FP4_SUPPORTED = {
ActivationType.Swiglu,
ActivationType.Geglu,
ActivationType.Relu2,
ActivationType.Identity,
}
assert fi_activation in _CUTLASS_FP4_SUPPORTED, (
f"Activation {activation!r} (is_gated={moe_runner_config.is_gated}) "
f"maps to {fi_activation.name}, which is not supported by the "
"flashinfer cutlass fp4 moe kernel."
)
# TRTLLM Cutlass moe takes in activations in BF16/Half/nvfp4 precision
# and fp4 quantized weights loaded from the checkpoint
x = dispatch_output.hidden_states
x_sf = dispatch_output.hidden_states_scale
topk_output = dispatch_output.topk_output
topk_weights, topk_ids = topk_output.topk_weights, topk_output.topk_ids
output_dtype = torch.bfloat16
if DispatchOutputChecker.format_is_flashinfer(dispatch_output):
symm_output = dispatch_output.moe_output
else:
# If x_sf is not None, x is FP4 packed (half size), so we need * 2
# If x_sf is None, x is not packed, so output_col = x.shape[1]
output_col = x.shape[1]
if x_sf is not None and layer.moe_runner_config.is_gated:
output_col *= 2
with use_symmetric_memory(
get_tp_group(), disabled=not is_allocation_symmetric()
):
symm_output = torch.empty(
x.shape[0],
output_col,
dtype=output_dtype,
device=x.device,
)
output = flashinfer_cutlass_fused_moe(
output=symm_output,
input=x,
token_selected_experts=topk_ids.to(torch.int),
token_final_scales=topk_weights,
fc1_expert_weights=layer.w13_weight.view(torch.long),
fc2_expert_weights=layer.w2_weight.view(torch.long),
output_dtype=output_dtype,
input_sf=x_sf,
# swizzled_input_sf intentionally omitted; not used for this path.
quant_info = FlashInferCutlassMoeQuantInfo(
quant_type="fp4",
w13_weight=layer.w13_weight,
w2_weight=layer.w2_weight,
output_dtype=torch.bfloat16,
quant_scales=[
layer.w13_input_scale_quant,
layer.w13_blockscale_swizzled.view(torch.int32),
layer.w13_blockscale_swizzled,
layer.g1_alphas,
layer.w2_input_scale_quant,
layer.w2_blockscale_swizzled.view(torch.int32),
layer.w2_blockscale_swizzled,
layer.g2_alphas,
],
ep_size=layer.moe_ep_size,
ep_rank=layer.moe_ep_rank,
tp_size=layer.moe_tp_size,
tp_rank=layer.moe_tp_rank,
tune_max_num_tokens=next_power_of_2(x.shape[0]),
activation_type=fi_activation,
enable_alltoall=get_moe_a2a_backend().is_flashinfer(),
)[0]
return StandardCombineInput(hidden_states=output)
moe_ep_size=layer.moe_ep_size,
moe_ep_rank=layer.moe_ep_rank,
moe_tp_size=layer.moe_tp_size,
moe_tp_rank=layer.moe_tp_rank,
apply_routed_scaling_factor=False,
)
return self.runner.run(dispatch_output, quant_info)
from sglang.srt.layers.moe.cutlass_moe import cutlass_moe_fp4
@@ -1039,7 +1039,7 @@ class Mxfp4MoEMethod(FusedMoEMethodBase):
):
# Register the fused func at runner construction so the FusedOpPool
# lookup at `MoeRunner.__init__` finds it.
import sglang.srt.layers.moe.moe_runner.flashinfer_mxfp4 # noqa: F401
import sglang.srt.layers.moe.moe_runner.flashinfer_cutlass # noqa: F401
self.runner = MoeRunner(moe_runner_backend, moe_runner_config)
else:
@@ -1051,12 +1051,12 @@ class Mxfp4MoEMethod(FusedMoEMethodBase):
"""SM90 (Hopper) MXFP4 x BF16 MoE via FlashInfer's cutlass mixed-input
path (PR #3084). Routed through the unified ``MoeRunner`` -- this
helper only builds the quant_info; the actual kernel call lives in
:mod:`sglang.srt.layers.moe.moe_runner.flashinfer_mxfp4`."""
from sglang.srt.layers.moe.moe_runner.flashinfer_mxfp4 import (
FlashInferMxfp4CutlassMoeQuantInfo,
:mod:`sglang.srt.layers.moe.moe_runner.flashinfer_cutlass`."""
from sglang.srt.layers.moe.moe_runner.flashinfer_cutlass import (
FlashInferCutlassMxfp4MoeQuantInfo,
)
quant_info = FlashInferMxfp4CutlassMoeQuantInfo(
quant_info = FlashInferCutlassMxfp4MoeQuantInfo(
w13_weight=layer.w13_weight,
w2_weight=layer.w2_weight,
w13_weight_scale=layer.w13_weight_scale,
@@ -145,7 +145,7 @@ class Mxfp4FlashinferCutlassMoEMethod:
# Register the fused func at runner construction so the FusedOpPool
# lookup at `MoeRunner.__init__` finds it.
import sglang.srt.layers.moe.moe_runner.flashinfer_mxfp4 # noqa: F401
import sglang.srt.layers.moe.moe_runner.flashinfer_cutlass # noqa: F401
self.runner = MoeRunner(MoeRunnerBackend.FLASHINFER_MXFP4, moe_runner_config)
@@ -217,8 +217,8 @@ class Mxfp4FlashinferCutlassMoEMethod:
layer: Module,
dispatch_output: DispatchOutput,
) -> CombineInput:
from sglang.srt.layers.moe.moe_runner.flashinfer_mxfp4 import (
FlashInferMxfp4CutlassMoeQuantInfo,
from sglang.srt.layers.moe.moe_runner.flashinfer_cutlass import (
FlashInferCutlassMxfp4MoeQuantInfo,
)
# DSv4 always feeds StandardDispatchOutput; the fused func tolerates
@@ -227,7 +227,7 @@ class Mxfp4FlashinferCutlassMoEMethod:
if not TopKOutputChecker.format_is_standard(topk_output):
raise ValueError(f"Unsupported topk output format: {topk_output.format}")
quant_info = FlashInferMxfp4CutlassMoeQuantInfo(
quant_info = FlashInferCutlassMxfp4MoeQuantInfo(
w13_weight=layer.w13_weight,
w2_weight=layer.w2_weight,
w13_weight_scale=layer.w13_weight_scale_inv,
@@ -35,7 +35,6 @@ from sglang.srt.utils import (
is_cpu,
is_hip,
is_npu,
next_power_of_2,
set_weight_attrs,
use_intel_amx_backend,
use_intel_xpu_backend,
@@ -62,12 +61,6 @@ if _use_aiter:
if _is_npu:
from sglang.srt.hardware_backend.npu.utils import npu_format_cast
try:
from flashinfer.fused_moe import cutlass_fused_moe as flashinfer_cutlass_fused_moe
from flashinfer.fused_moe.core import ActivationType
except ImportError:
flashinfer_cutlass_fused_moe = None
class UnquantizedEmbeddingMethod(QuantizeMethodBase):
"""Unquantized method for embeddings."""
@@ -412,6 +405,10 @@ class UnquantizedFusedMoEMethod(FusedMoEMethodBase, MultiPlatformOp):
if get_moe_runner_backend().is_flashinfer_trtllm_routed()
else MoeRunnerBackend.FLASHINFER_TRTLLM
)
elif self.use_flashinfer_cutlass:
import sglang.srt.layers.moe.moe_runner.flashinfer_cutlass # noqa: F401
backend = MoeRunnerBackend.FLASHINFER_CUTLASS
elif self.use_deep_gemm:
backend = MoeRunnerBackend.DEEP_GEMM
elif self.use_triton_kernels:
@@ -467,12 +464,8 @@ class UnquantizedFusedMoEMethod(FusedMoEMethodBase, MultiPlatformOp):
layer: torch.nn.Module,
dispatch_output: StandardDispatchOutput,
) -> CombineInput:
from sglang.srt.layers.moe.token_dispatcher import StandardCombineInput
x = dispatch_output.hidden_states
moe_runner_config = self.moe_runner_config
backend = self.runner.runner_backend
if backend.is_triton_kernels():
from sglang.srt.layers.moe.moe_runner.triton_kernels import (
@@ -501,34 +494,22 @@ class UnquantizedFusedMoEMethod(FusedMoEMethodBase, MultiPlatformOp):
)
return self.runner.run(dispatch_output, quant_info)
elif self.use_flashinfer_cutlass:
topk_output = dispatch_output.topk_output
output = flashinfer_cutlass_fused_moe(
input=x,
token_selected_experts=topk_output.topk_ids,
token_final_scales=topk_output.topk_weights,
fc1_expert_weights=layer.w13_weight,
fc2_expert_weights=layer.w2_weight,
from sglang.srt.layers.moe.moe_runner.flashinfer_cutlass import (
FlashInferCutlassMoeQuantInfo,
)
quant_info = FlashInferCutlassMoeQuantInfo(
quant_type="bf16",
w13_weight=layer.w13_weight,
w2_weight=layer.w2_weight,
output_dtype=x.dtype,
quant_scales=None,
ep_size=layer.moe_ep_size,
ep_rank=layer.moe_ep_rank,
tp_size=layer.moe_tp_size,
tp_rank=layer.moe_tp_rank,
tune_max_num_tokens=next_power_of_2(x.shape[0]),
activation_type=(
ActivationType.Relu2
if moe_runner_config.activation == "relu2"
else ActivationType.Swiglu
),
)[0]
if (
not layer.should_fuse_routed_scaling_factor_in_topk
and moe_runner_config.routed_scaling_factor is not None
):
output.mul_(moe_runner_config.routed_scaling_factor)
return StandardCombineInput(hidden_states=output)
moe_ep_size=layer.moe_ep_size,
moe_ep_rank=layer.moe_ep_rank,
moe_tp_size=layer.moe_tp_size,
moe_tp_rank=layer.moe_tp_rank,
apply_routed_scaling_factor=not layer.should_fuse_routed_scaling_factor_in_topk,
)
return self.runner.run(dispatch_output, quant_info)
elif self.use_flashinfer_trtllm_moe:
from sglang.srt.layers.moe.moe_runner.flashinfer_trtllm import (
FlashInferTrtllmBf16MoeQuantInfo,
@@ -171,7 +171,7 @@ def _build_flashinfer_mxfp4_runner(num_experts, hidden, inter):
and wires the runner with a minimal MoeRunnerConfig sufficient for the
cutlass SM90 fused func, which only reads dispatch_output / quant_info.
"""
import sglang.srt.layers.moe.moe_runner.flashinfer_mxfp4 # noqa: F401
import sglang.srt.layers.moe.moe_runner.flashinfer_cutlass # noqa: F401
from sglang.srt.layers.moe.moe_runner.base import MoeRunnerConfig
from sglang.srt.layers.moe.moe_runner.runner import MoeRunner
from sglang.srt.layers.moe.utils import MoeRunnerBackend
@@ -325,7 +325,7 @@ def test_apply_sm90_cutlass_matches_flashinfer_direct(
covered separately by ``test_process_weights_matches_direct_interleave``;
here we just verify that ``apply`` calls the kernel with the right
arguments (incl. input padding + output trim)."""
import sglang.srt.layers.moe.moe_runner.flashinfer_mxfp4 as fi_mxfp4_mod
import sglang.srt.layers.moe.moe_runner.flashinfer_cutlass as fi_cutlass_mod
import sglang.srt.layers.quantization.mxfp4 as mxfp4_mod
# Bypass symmetric-memory / TP-group in both the legacy quant_method and
@@ -336,10 +336,10 @@ def test_apply_sm90_cutlass_matches_flashinfer_direct(
monkeypatch.setattr(mxfp4_mod, "is_allocation_symmetric", lambda: False)
monkeypatch.setattr(mxfp4_mod, "get_tp_group", lambda: None)
monkeypatch.setattr(
fi_mxfp4_mod, "use_symmetric_memory", lambda *a, **kw: nullcontext()
fi_cutlass_mod, "use_symmetric_memory", lambda *a, **kw: nullcontext()
)
monkeypatch.setattr(fi_mxfp4_mod, "is_allocation_symmetric", lambda: False)
monkeypatch.setattr(fi_mxfp4_mod, "get_tp_group", lambda: None)
monkeypatch.setattr(fi_cutlass_mod, "is_allocation_symmetric", lambda: False)
monkeypatch.setattr(fi_cutlass_mod, "get_tp_group", lambda: None)
w13, w2, w13_s, w2_s, w13_b, w2_b = _make_random_mxfp4(num_experts, hidden, inter)
x = torch.randn(tokens, hidden, dtype=torch.bfloat16, device="cuda") * 0.1
@@ -463,17 +463,17 @@ def test_dsv4_apply_matches_flashinfer_direct(
the equivalent reorder + scale-cast + interleave applied manually."""
from types import SimpleNamespace
import sglang.srt.layers.moe.moe_runner.flashinfer_mxfp4 as fi_mxfp4_mod
import sglang.srt.layers.moe.moe_runner.flashinfer_cutlass as fi_cutlass_mod
import sglang.srt.layers.quantization.mxfp4_flashinfer_cutlass_moe as ds_mod
from sglang.srt.layers.quantization.utils import reorder_w1w3_to_w3w1
# Bypass symmetric-memory / TP-group stack in the new fused-func module
# (where DSv4 ``apply`` now dispatches the kernel call through).
monkeypatch.setattr(
fi_mxfp4_mod, "use_symmetric_memory", lambda *a, **kw: nullcontext()
fi_cutlass_mod, "use_symmetric_memory", lambda *a, **kw: nullcontext()
)
monkeypatch.setattr(fi_mxfp4_mod, "is_allocation_symmetric", lambda: False)
monkeypatch.setattr(fi_mxfp4_mod, "get_tp_group", lambda: None)
monkeypatch.setattr(fi_cutlass_mod, "is_allocation_symmetric", lambda: False)
monkeypatch.setattr(fi_cutlass_mod, "get_tp_group", lambda: None)
w13, w2, w13_s, w2_s = _make_random_dsv4_mxfp4(num_experts, hidden, inter)
x = torch.randn(tokens, hidden, dtype=torch.bfloat16, device="cuda") * 0.1