[3/N][Feat][Graph] Support all-to-all and quantized models with ACL Graph (#2614)

### What this PR does / why we need it?
* **Unify execution paths:** Consolidates the quantized and
non-quantized execution paths into a single `fused_experts` function,
removing duplicated logic and making the control flow clearer and easier
to maintain.
* **W8A8 dynamic quantization:** Adds support for W8A8 dynamic
quantization inside the unified MoE kernel. Communication routines are
updated to correctly handle dynamic quantization scales for activations.
* **Weight pre-processing:** Prae-transpose the `w13` and `w2` weight
matrices (as implemented in PR #2025) so that quantized and
non-quantized models follow the same code path for the MoE gating,
up-projection, and down-projection operations.
* **All-to-all communication:** Adds an `all-to-all` collective
communication pattern. For large token counts on modern hardware,
`all-to-all` is more efficient than the previous `all-gather` strategy.
However, `all-to-all` is not really captured and replayed due to
multiple D2H operations which will trigger synchronization, and thus
raise error when capture graphs. We only use `all-to-all` when fallback
to `compiled_graph_for_general_shape`.
* **Dynamic communication selection:** The model runner now selects the
optimal MoE communication method (`mc2`, `allgather`, or `alltoall`) at
runtime based on token count and the Ascend SoC version.
* **Limitation:** `all-gather` is not yet supported for quantized
models, which means there is still something left to do on A2.

### Does this PR introduce _any_ user-facing change?
None.

### How was this patch tested?
No further test cases needed.

- vLLM version: v0.10.1.1
- vLLM main:
d660c98c1b

---------

Signed-off-by: Yizhou Liu <liu_yizhou@outlook.com>
This commit is contained in:
yiz-liu
2025-08-30 11:00:35 +08:00
committed by GitHub
parent 91c35d765a
commit d3c93fba5c
7 changed files with 248 additions and 41 deletions

View File

@@ -33,6 +33,7 @@ from vllm_ascend.distributed.moe_comm_method import ( # isort: skip
@pytest.mark.parametrize("top_k_num", [2, 4])
@pytest.mark.parametrize("dtype", [torch.bfloat16, torch.float16])
@pytest.mark.parametrize("ep_rank", [0, 1])
@pytest.mark.parametrize("apply_a8_quantization", [False])
def test_all_gather_comm_impl(
num_tokens,
hidden_size,
@@ -41,6 +42,7 @@ def test_all_gather_comm_impl(
top_k_num,
dtype,
ep_rank,
apply_a8_quantization,
mocker,
):
"""
@@ -118,8 +120,9 @@ def test_all_gather_comm_impl(
native_permuted_hidden,
native_expert_tokens,
_,
_,
) = native_impl.permute(hidden_states, topk_ids, topk_weights, expert_map,
num_experts)
num_experts, apply_a8_quantization)
# Simulate MLP output
native_mlp_output = torch.randn_like(native_permuted_hidden)
native_impl.unpermute(native_mlp_output, native_hidden_states_out)
@@ -130,8 +133,9 @@ def test_all_gather_comm_impl(
all_gather_permuted_hidden,
all_gather_expert_tokens,
_,
_,
) = all_gather_impl.permute(hidden_states, topk_ids, topk_weights,
expert_map, num_experts)
expert_map, num_experts, apply_a8_quantization)
# Use the same simulated MLP output for a fair comparison
all_gather_mlp_output = native_mlp_output.clone()

View File

@@ -107,4 +107,4 @@ def test_models_distributed_Qwen3_MOE_TP2_WITH_ACLGRAPH():
tensor_parallel_size=2,
enforce_eager=False,
) as vllm_model:
vllm_model.generate_greedy(example_prompts, max_tokens)
vllm_model.generate_greedy(example_prompts, max_tokens)

View File

@@ -54,7 +54,8 @@ class MoECommMethod(ABC):
topk_weights: torch.Tensor,
expert_map: torch.Tensor,
num_experts: int,
) -> tuple[torch.Tensor, torch.Tensor, int]:
apply_a8_quantization: bool,
) -> tuple[torch.Tensor, torch.Tensor, Optional[torch.Tensor], int]:
"""Pre-process before MLP.
Args:
@@ -64,6 +65,7 @@ class MoECommMethod(ABC):
expert_map (torch.Tensor): Tensor of shape (global_num_experts, )
Mapping from global expert IDs to local expert IDs.
num_experts (int): Number of local experts (experts on this device).
apply_a8_quantization (bool): Whether to apply A8 quantization (W4A8 and W8A8).
Returns:
tuple[torch.Tensor, torch.Tensor, int]: Return a tuple containing:
@@ -72,6 +74,8 @@ class MoECommMethod(ABC):
hidden_states based on topk_ids.
- expert_tokens (torch.Tensor): Tensor of shape (num_experts, )
Number of tokens assigned to each expert.
- dynamic_scale (torch.Tensor, optional): Tensor of shape (num_experts, )
Dynamic scale for each expert, used for quantization.
- group_list_type (int): Type of group list, 0 for `cumsum`
and 1 for `count`. This is mainly for `npu_grouped_matmul`
to determine how to handle the output.
@@ -159,7 +163,8 @@ class AllGatherCommImpl(MoECommMethod):
topk_weights: torch.Tensor,
expert_map: torch.Tensor, # noqa: F841
num_experts: int,
) -> tuple[torch.Tensor, torch.Tensor, int]:
apply_a8_quantization: bool,
) -> tuple[torch.Tensor, torch.Tensor, Optional[torch.Tensor], int]:
num_tokens = hidden_states.shape[0]
self.topk_weights = topk_weights
@@ -194,7 +199,7 @@ class AllGatherCommImpl(MoECommMethod):
group_list_type = 1 # `count` mode
return permuted_hidden_states, expert_tokens, group_list_type
return permuted_hidden_states, expert_tokens, None, group_list_type
def unpermute(self, mlp_output: torch.Tensor,
hidden_states: torch.Tensor) -> None:
@@ -219,7 +224,8 @@ class NativeAllGatherCommImpl(AllGatherCommImpl):
topk_weights: torch.Tensor,
expert_map: torch.Tensor,
num_experts: int,
) -> tuple[torch.Tensor, torch.Tensor, int]:
apply_a8_quantization: bool,
) -> tuple[torch.Tensor, torch.Tensor, Optional[torch.Tensor], int]:
num_tokens = hidden_states.shape[0]
# Generate token indices and flatten
@@ -269,7 +275,7 @@ class NativeAllGatherCommImpl(AllGatherCommImpl):
group_list_type = 1 # `count` mode
return permuted_hidden_states, expert_tokens, group_list_type
return permuted_hidden_states, expert_tokens, None, group_list_type
def unpermute(self, mlp_output: torch.Tensor,
hidden_states: torch.Tensor) -> None:
@@ -375,7 +381,8 @@ class MC2CommImpl(MoECommMethod):
topk_weights: torch.Tensor,
expert_map: torch.Tensor,
num_experts: int,
) -> tuple[torch.Tensor, torch.Tensor, int]:
apply_a8_quantization: bool,
) -> tuple[torch.Tensor, torch.Tensor, Optional[torch.Tensor], int]:
# Store tensors needed for post_process
self.topk_ids = topk_ids
self.topk_weights = topk_weights.to(torch.float32)
@@ -388,7 +395,7 @@ class MC2CommImpl(MoECommMethod):
"moe_expert_num": self.moe_config.num_experts,
"global_bs": 0,
"scales": None,
"quant_mode": 0,
"quant_mode": 2 if apply_a8_quantization else 0,
"group_ep": self.mc2_comm_name,
"ep_world_size": self.moe_config.ep_size,
"ep_rank_id": self.moe_config.ep_rank,
@@ -409,7 +416,7 @@ class MC2CommImpl(MoECommMethod):
(
permuted_hidden_states,
_, # dynamic_scale is not used
dynamic_scale,
self.assist_info_for_combine,
expert_tokens,
self.ep_recv_counts,
@@ -418,7 +425,7 @@ class MC2CommImpl(MoECommMethod):
group_list_type = 1
return permuted_hidden_states, expert_tokens, group_list_type
return permuted_hidden_states, expert_tokens, dynamic_scale, group_list_type
def unpermute(self, mlp_output: torch.Tensor,
hidden_states: torch.Tensor) -> None:
@@ -457,3 +464,93 @@ class MC2CommImpl(MoECommMethod):
combine = torch_npu.npu_moe_distribute_combine_v2 if self.enable_dispatch_v2 else torch_npu.npu_moe_distribute_combine
hidden_states[:] = combine(**combine_kwargs)
class AlltoAllCommImpl(MoECommMethod):
"""This implementation is for the scenarios listed below:
1. `enable_expert_parallel=True`.
2. `npu_grouped_matmul` is available.
This implementation uses all-to-all communication to exchange tokens
between data parallel ranks before and after the MLP computation. It should
have better performance than AllGatherCommImpl when DP size > 1.
"""
def __init__(self, moe_config: Optional[FusedMoEConfig]):
super().__init__(moe_config)
from vllm_ascend.ops.moe_dispatcher.token_dispatcher import \
get_token_dispatcher
self.token_dispatcher = get_token_dispatcher(
"TokenDispatcherWithAll2AllV")
self._restore_tp_across_dp()
def _restore_tp_across_dp(self):
# NOTE: Since vLLM flatten tp across dp, we need to restore the original
# tp_size and tp_rank.
self.tp_size = get_tensor_model_parallel_world_size()
self.tp_rank = get_tensor_model_parallel_rank()
def prepare(
self, hidden_states: torch.Tensor,
router_logits: torch.Tensor) -> tuple[torch.Tensor, torch.Tensor]:
self.num_tokens, _ = hidden_states.shape
pad_size = self.tp_size - self.num_tokens
if pad_size > 0:
hidden_states = nn.functional.pad(hidden_states,
(0, 0, 0, pad_size))
router_logits = nn.functional.pad(router_logits,
(0, 0, 0, pad_size))
if self.tp_size > 1:
split_hidden_states = torch.tensor_split(hidden_states,
self.tp_size,
dim=0)
split_router_logits = torch.tensor_split(router_logits,
self.tp_size,
dim=0)
self.split_hidden_states = split_hidden_states
hidden_states = split_hidden_states[self.tp_rank]
router_logits = split_router_logits[self.tp_rank]
return hidden_states, router_logits
def finalize(self, hidden_states: torch.Tensor,
reduce_results: bool) -> torch.Tensor:
"""If TP size > 1, all-gather the hidden states to get the final output.
Also, unpad the hidden states if needed.
"""
if self.tp_size > 1:
dist.all_gather(list(self.split_hidden_states), hidden_states,
self.moe_config.tp_group.device_group)
hidden_states = torch.cat(self.split_hidden_states, dim=0)
if self.num_tokens < hidden_states.shape[0]:
hidden_states = hidden_states[:self.num_tokens]
return hidden_states
def permute(
self,
hidden_states: torch.Tensor,
topk_ids: torch.Tensor,
topk_weights: torch.Tensor,
expert_map: torch.Tensor,
num_experts: int,
apply_a8_quantization: bool,
) -> tuple[torch.Tensor, torch.Tensor, Optional[torch.Tensor], int]:
results = self.token_dispatcher.token_dispatch(
hidden_states,
topk_weights,
topk_ids,
None,
log2phy=None,
with_quant=apply_a8_quantization)
return results["hidden_states"], results["group_list"], results[
"dynamic_scale"], results["group_list_type"]
def unpermute(self, mlp_output: torch.Tensor,
hidden_states: torch.Tensor) -> None:
hidden_states[:] = self.token_dispatcher.token_combine(mlp_output)

View File

@@ -18,6 +18,7 @@
from typing import Any, Callable, Optional
import torch
import torch_npu
from vllm.config import CompilationLevel, get_current_vllm_config
from vllm.distributed import get_dp_group, get_ep_group, get_tp_group
from vllm.forward_context import get_forward_context
@@ -26,12 +27,14 @@ from vllm.model_executor.layers.fused_moe.layer import (
from vllm_ascend.ascend_config import get_ascend_config
from vllm_ascend.distributed.moe_comm_method import (AllGatherCommImpl,
MC2CommImpl,
MoECommMethod)
AlltoAllCommImpl,
MC2CommImpl)
from vllm_ascend.distributed.parallel_state import get_mc2_group
from vllm_ascend.ops.fused_moe import apply_mlp, fused_experts_moge
from vllm_ascend.ops.fused_moe import fused_experts_moge
from vllm_ascend.ops.layers.experts_selector import select_experts
from vllm_ascend.utils import is_310p
from vllm_ascend.ops.moe_dispatcher.token_dispatcher import \
setup_token_dispatchers
from vllm_ascend.utils import ACL_FORMAT_FRACTAL_NZ, is_310p
original_unquantized_fused_moe_init_func = UnquantizedFusedMoEMethod.__init__
@@ -52,7 +55,6 @@ def fused_experts(
w2_scale: Optional[torch.Tensor] = None,
w1_scale_bias: torch.Tensor = None,
w2_scale_bias: torch.Tensor = None,
moe_comm_method: Optional[MoECommMethod] = None,
# For TorchAir graph
is_torchair: bool = False,
# For Cube/Vector parallel
@@ -64,9 +66,8 @@ def fused_experts(
global_redundant_expert_num: int = 0,
) -> torch.Tensor:
# Check constraints
assert hidden_states.shape[1] == w1.shape[2], (
f"Hidden size mismatch {hidden_states.shape[1]} != {w1.shape[2]}")
assert hidden_states.shape[1] == w1.shape[1], (
f"Hidden size mismatch {hidden_states.shape[1]} != {w1.shape[1]}")
assert topk_weights.shape == topk_ids.shape, "topk shape mismatch"
assert hidden_states.is_contiguous(), "Hidden_states must be contiguous"
assert w1.stride(-1) == 1, "Stride of last dimension must be 1"
@@ -74,31 +75,79 @@ def fused_experts(
assert hidden_states.dtype in [
torch.float32, torch.float16, torch.bfloat16
]
if (use_int8_w8a8 or use_int4_w4a8):
assert w1_scale is not None and w2_scale is not None, \
"INT8 quantization requires weight scales."
w1_scale = w1_scale.to(torch.float32)
down_scale = [w2_scale]
down_output_dtype = w2_scale.dtype
else:
down_scale = None
down_output_dtype = None
moe_comm_method = get_forward_context().moe_comm_method
assert moe_comm_method is not None, "Missing communication context"
num_experts = w1.shape[0]
permuted_hidden_states, expert_tokens, group_list_type = moe_comm_method.permute(
hidden_states, topk_ids, topk_weights, expert_map, num_experts)
mlp_output = apply_mlp(
permuted_hidden_states,
w1,
w2,
expert_tokens,
permuted_hidden_states, expert_tokens, dynamic_scale, group_list_type = moe_comm_method.permute(
hidden_states, topk_ids, topk_weights, expert_map, num_experts,
use_int8_w8a8 or use_int4_w4a8)
gate_up_output = torch_npu.npu_grouped_matmul(
x=[permuted_hidden_states],
weight=[w1],
split_item=2,
group_list_type=group_list_type,
)
moe_comm_method.unpermute(mlp_output, hidden_states)
group_type=0,
group_list=expert_tokens,
output_dtype=torch.int32 if use_int8_w8a8 else None,
)[0]
if (use_int8_w8a8 or use_int4_w4a8):
activated_output, activated_output_scale = torch_npu.npu_dequant_swiglu_quant(
x=gate_up_output,
weight_scale=w1_scale,
activation_scale=dynamic_scale,
bias=None,
quant_scale=None,
quant_offset=None,
group_index=expert_tokens,
activate_left=True,
quant_mode=1,
)
activated_output_scale = [activated_output_scale]
else:
activated_output = torch_npu.npu_swiglu(gate_up_output)
activated_output_scale = None
down_output = torch_npu.npu_grouped_matmul(
x=[activated_output],
weight=[w2],
scale=down_scale,
per_token_scale=activated_output_scale,
split_item=2,
group_list_type=group_list_type,
group_type=0,
group_list=expert_tokens,
output_dtype=down_output_dtype,
)[0]
moe_comm_method.unpermute(down_output, hidden_states)
return hidden_states
def unquantized_fused_moe_init_func(self, *args, **kwargs):
original_unquantized_fused_moe_init_func(self, *args, **kwargs)
# NOTE: Currently, this self.use_aclgraph is only used in
# UnquantizedFusedMoEMethod.forward_oot to decide whether to use in
# ops/fused_moe.py:568 to circumvent torch.randint_like not supported issue.
# Once torch.randint_like is supported or removed, this flag can be removed.
vllm_config = get_current_vllm_config()
self.max_num_batched_tokens = vllm_config.scheduler_config.max_num_batched_tokens
ascend_config = get_ascend_config()
if ascend_config.torchair_graph_config.enabled:
self.use_aclgraph = False
else:
@@ -156,8 +205,6 @@ def forward_oot(
expert_map=expert_map,
apply_router_weight_on_input=apply_router_weight_on_input)
moe_comm_method = get_forward_context().moe_comm_method
return fused_experts(
hidden_states=x,
w1=layer.w13_weight,
@@ -166,10 +213,26 @@ def forward_oot(
topk_ids=topk_ids,
global_num_experts=global_num_experts,
expert_map=expert_map,
moe_comm_method=moe_comm_method,
)
def process_weights_after_loading(self, layer):
super(UnquantizedFusedMoEMethod, self).process_weights_after_loading(layer)
w13_data = self._maybe_pad_weight(layer.w13_weight.data).transpose(
1, 2).contiguous()
layer.w13_weight = torch.nn.Parameter(w13_data, requires_grad=False)
w2_data = self._maybe_pad_weight(layer.w2_weight.data).transpose(
1, 2).contiguous()
layer.w2_weight = torch.nn.Parameter(w2_data, requires_grad=False)
if not is_310p():
layer.w13_weight.data = torch_npu.npu_format_cast(
layer.w13_weight.data, ACL_FORMAT_FRACTAL_NZ)
layer.w2_weight.data = torch_npu.npu_format_cast(
layer.w2_weight.data, ACL_FORMAT_FRACTAL_NZ)
class AscendFusedMoE(FusedMoE):
def __init__(
@@ -224,12 +287,17 @@ class AscendFusedMoE(FusedMoE):
has_bias,
)
setup_token_dispatchers(self.moe_config.ep_size,
top_k=self.top_k,
num_experts=self.global_num_experts,
num_local_experts=self.local_num_experts)
self.moe_config.tp_group = get_tp_group()
self.moe_config.dp_group = get_dp_group()
self.moe_config.ep_group = get_ep_group()
self.moe_config.mc2_group = get_mc2_group()
for method in {AllGatherCommImpl, MC2CommImpl}:
for method in {AllGatherCommImpl, AlltoAllCommImpl, MC2CommImpl}:
setattr(
self, method.__name__.lower(),
method(moe_config=self.moe_config)) # type: ignore[abstract]
@@ -282,4 +350,5 @@ class AscendFusedMoE(FusedMoE):
UnquantizedFusedMoEMethod.__init__ = unquantized_fused_moe_init_func
UnquantizedFusedMoEMethod.process_weights_after_loading = process_weights_after_loading
UnquantizedFusedMoEMethod.forward_oot = forward_oot

View File

@@ -230,7 +230,6 @@ def fused_experts_moge(
0, sorted_topk_ids).unsqueeze(-1)
group_list = num_tokens_per_expert.cumsum(dim=0).to(torch.int64)
w1 = w1.transpose(1, 2)
gate_up_out = torch_npu.npu_grouped_matmul(
x=[sorted_hidden_states],
weight=[w1],
@@ -247,7 +246,6 @@ def fused_experts_moge(
gate_up_out = torch_npu.npu_swiglu(gate_up_out)
gate_up_out *= topk_scales
w2 = w2.transpose(1, 2)
down_out_list = torch_npu.npu_grouped_matmul(
x=[gate_up_out],
weight=[w2],

View File

@@ -19,12 +19,16 @@ from typing import Any, Callable, Dict, Optional, Tuple, Union
import torch
import torch_npu
from vllm.config import CompilationLevel, get_current_vllm_config
from vllm.distributed import get_ep_group
from vllm.forward_context import get_forward_context
import vllm_ascend.envs as envs_ascend
from vllm_ascend.ascend_config import get_ascend_config
from vllm_ascend.ascend_forward_context import FusedMoEState
from vllm_ascend.distributed.parallel_state import get_mc2_group
from vllm_ascend.ops.common_fused_moe import \
fused_experts as unified_fused_experts
from vllm_ascend.ops.fused_moe import unified_fused_experts_eager
from vllm_ascend.ops.layers.experts_selector import select_experts
from vllm_ascend.utils import ACL_FORMAT_FRACTAL_NZ, dispose_tensor
@@ -283,6 +287,13 @@ class AscendW8A8DynamicFusedMoEMethod:
self.ep_group = get_ep_group()
vllm_config = get_current_vllm_config()
ascend_config = get_ascend_config()
self.use_aclgraph = (
vllm_config.compilation_config.level == CompilationLevel.PIECEWISE
and not vllm_config.model_config.enforce_eager
and not ascend_config.torchair_graph_config.enabled)
try:
device_group = get_mc2_group().device_group
# TODO: Try local_rank = ep_group.rank_in_group
@@ -375,6 +386,19 @@ class AscendW8A8DynamicFusedMoEMethod:
e_score_correction_bias=e_score_correction_bias,
global_num_experts=global_num_experts)
if self.use_aclgraph:
return unified_fused_experts(
hidden_states=x,
w1=layer.w13_weight,
w2=layer.w2_weight,
topk_weights=topk_weights,
topk_ids=topk_ids,
use_int8_w8a8=True,
w1_scale=layer.w13_weight_scale,
w2_scale=layer.w2_weight_scale,
expert_map=expert_map,
)
fused_moe_state = get_forward_context().fused_moe_state
shared_gate_up, shared_dequant_scale = None, None
if shared_experts is not None and fused_moe_state == FusedMoEState.MC2:

View File

@@ -89,7 +89,8 @@ from vllm_ascend.sample.rejection_sampler import AscendRejectionSampler
from vllm_ascend.torchair.torchair_attention import AscendTorchairMetadata
from vllm_ascend.torchair.torchair_mla import AscendMLATorchairMetadata
from vllm_ascend.utils import (ACL_FORMAT_FRACTAL_ND, ACL_FORMAT_FRACTAL_NZ,
ProfileExecuteDuration, is_310p,
AscendSocVersion, ProfileExecuteDuration,
get_ascend_soc_version, is_310p,
lmhead_tp_enable, vllm_version_is)
from vllm_ascend.worker.eagle_proposer_v1 import EagleProposer
from vllm_ascend.worker.mtp_proposer_v1 import MtpProposer
@@ -1620,8 +1621,22 @@ class NPUModelRunner(LoRAModelRunnerMixin):
)
def _select_moe_comm_method(self, num_tokens: int) -> str:
return ("mc2"
if num_tokens <= self.mc2_tokens_capacity else "allgather")
soc_version = get_ascend_soc_version()
if num_tokens <= self.mc2_tokens_capacity:
moe_comm_method = "mc2"
elif soc_version in {AscendSocVersion.A2}:
moe_comm_method = "allgather"
elif soc_version in {AscendSocVersion.A3}:
moe_comm_method = "alltoall"
else:
raise ValueError(f"Unsupported soc_version: {soc_version}")
if is_global_first_rank():
logger.debug(f"num_tokens: {num_tokens}, "
f"moe_comm_method: {moe_comm_method}")
return moe_comm_method
@torch.inference_mode()
def execute_model(