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sglang/python/sglang/srt/layers/quantization/modelslim/modelslim.py
2026-03-11 16:52:35 +03:00

405 lines
14 KiB
Python

from __future__ import annotations
import logging
from types import MappingProxyType
from typing import TYPE_CHECKING, Any, Dict, List, Mapping, Optional, Tuple, Union, cast
import torch
from sglang.srt.hardware_backend.npu.quantization.linear_method_npu import (
_NPULinearMethodBase,
)
from sglang.srt.layers.quantization.base_config import (
FusedMoEMethodBase,
QuantizationConfig,
)
from sglang.srt.layers.quantization.compressed_tensors.utils import should_ignore_layer
from sglang.srt.layers.quantization.modelslim.schemes import (
ModelSlimW4A4Int4,
ModelSlimW4A4Int4MoE,
ModelSlimW4A8Int8MoE,
ModelSlimW8A8Int8,
ModelSlimW8A8Int8MoE,
)
from sglang.srt.layers.quantization.unquant import UnquantizedLinearMethod
from sglang.srt.utils import apply_module_patch
if TYPE_CHECKING:
from sglang.srt.layers.moe import MoeRunnerConfig
from sglang.srt.layers.moe.token_dispatcher import (
CombineInput,
StandardDispatchOutput,
)
from sglang.srt.layers.quantization.base_config import QuantizeMethodBase
from sglang.srt.layers.quantization.modelslim.schemes import (
ModelSlimLinearScheme,
ModelSlimMoEScheme,
)
logger = logging.getLogger(__name__)
# func refers to RMSNorm.__init__
def npu_wrapper_rmsnorm_init(func):
def init(self, hidden_size: int, **extra_args) -> None:
func(self, hidden_size, **extra_args)
self.ignore_anti = True
# The Ascend w8a8_int8 quantization requires adding a bias in rmsnorm
self.bias = torch.nn.Parameter(torch.zeros(hidden_size), requires_grad=False)
return init
# func refers to RMSNorm.forward_oot
def npu_wrapper_rmsnorm_forward(func):
def _rmsnorm_forward_oot(
self,
x: torch.Tensor,
residual: Optional[torch.Tensor] = None,
post_residual_addition: Optional[torch.Tensor] = None,
) -> Union[torch.Tensor, Tuple[torch.Tensor, torch.Tensor]]:
from sgl_kernel_npu.norm.add_rmsnorm_bias import add_rmsnorm_bias
if not x.is_contiguous():
x = x.contiguous()
if residual is not None:
if post_residual_addition is not None:
residual = residual + post_residual_addition
out, residual_out = add_rmsnorm_bias(
x,
residual,
self.weight.data,
self.bias,
self.variance_epsilon,
)
return out.to(x.dtype), residual_out
out = torch.ops.npu.npu_rms_norm(x, self.weight.data, self.variance_epsilon)[0]
out = out + self.bias
return out.to(x.dtype)
return _rmsnorm_forward_oot
class ModelSlimConfig(QuantizationConfig):
"""
Config class for ModelSlim Quantization, a NPU-specific quantization type.
"""
def __init__(self, quant_config: Dict[str, Any] = {}):
super().__init__()
self.quant_description = quant_config
ignore = cast(List[str], quant_config.get("ignore", []))
self.ignore = ignore if ignore is not None else []
packed_modules_mapping = quant_config.get("packed_modules_mapping", {})
self.packed_modules_mapping = (
packed_modules_mapping if packed_modules_mapping is not None else {}
)
for name in self.quant_description.keys():
if "norm.bias" in name:
apply_module_patch(
"sglang.srt.layers.layernorm.RMSNorm",
"__init__",
[npu_wrapper_rmsnorm_init],
)
apply_module_patch(
"sglang.srt.layers.layernorm.RMSNorm",
"forward_npu",
[npu_wrapper_rmsnorm_forward],
)
def get_linear_method(self) -> ModelSlimLinearMethod:
return ModelSlimLinearMethod(self)
@classmethod
def get_supported_act_dtypes(cls) -> List[torch.dtype]:
return [torch.int8, torch.float16, torch.bfloat16]
@classmethod
def get_min_capability(cls) -> int:
return 0
@classmethod
def get_name(cls) -> str:
return "modelslim"
@classmethod
def get_config_filenames(cls) -> List[str]:
filenames = ["quant_model_description.json"]
return filenames
@classmethod
def from_config(cls, config: Dict[str, Any]) -> ModelSlimConfig:
return cls(config)
def get_quant_method(
self,
layer: torch.nn.Module,
prefix: str,
) -> Optional[QuantizeMethodBase]:
from sglang.srt.layers.linear import LinearBase
from sglang.srt.layers.moe.fused_moe_triton import FusedMoE
if isinstance(layer, LinearBase):
if should_ignore_layer(
prefix,
ignore=self.ignore,
fused_mapping=self.packed_modules_mapping,
):
return UnquantizedLinearMethod()
key = "model"
if "vision_model" in prefix:
key = "vision_model"
elif "visual" in prefix:
key = "visual"
if "vision_tower" in prefix or "mm_projector" in prefix:
prefix = prefix.replace(r"attn.qkv_proj", r"wqkv")
prefix = prefix.replace(r"attn.proj", r"wo")
packed_modules_mapping_subset = self.packed_modules_mapping.get(key, {})
prefix_in_quant_config = prefix
proj_name = prefix.split(".")[-1]
if proj_name in packed_modules_mapping_subset:
prefix_in_quant_config = prefix.replace(
proj_name, packed_modules_mapping_subset[proj_name][0]
)
if self.is_layer_skipped(prefix, packed_modules_mapping_subset):
return UnquantizedLinearMethod()
scheme = self.get_linear_scheme(
layer=layer, layer_name=prefix_in_quant_config
)
layer.scheme = scheme
return ModelSlimLinearMethod(self)
elif isinstance(layer, FusedMoE):
layer.scheme = self.get_moe_scheme(layer, prefix)
return ModelSlimFusedMoEMethod(self)
return None
def _get_scheme_from_parts(
self,
layer_name: str,
) -> ModelSlimLinearScheme:
quant_type = self.quant_description.get(layer_name + ".weight", "")
if quant_type == "W8A8_DYNAMIC" or quant_type == "W8A8":
return ModelSlimW8A8Int8(
quant_config=self.quant_description, prefix=layer_name
)
elif quant_type == "W4A4_DYNAMIC":
return ModelSlimW4A4Int4(
quant_config=self.quant_description, prefix=layer_name
)
raise NotImplementedError("No modelslim compatible scheme was found.")
def get_linear_scheme(
self, layer: torch.nn.Module, layer_name: Optional[str] = None
) -> Optional[ModelSlimLinearScheme]:
"""
get_scheme method adjusted for modelslim, taken from
python/sglang/srt/layers/quantization/compressed_tensors/compressed_tensors.py
"""
scheme = self._get_scheme_from_parts(
layer_name=layer_name,
)
# Ascend doesn't support device capability
logger.debug("Using scheme: %s for %s", scheme.__class__.__name__, layer_name)
return scheme
def get_moe_scheme(
self,
layer: torch.nn.Module,
prefix: str,
) -> Optional[ModelSlimMoEScheme]:
# TODO: @dsikka: refactor this to use schemes as other kernels
# are supported + check if the layer is being ignored.
prefix_in_quant_config = prefix + ".0.gate_proj.weight"
is_moe_w4a4_dynamic = (
self.quant_description.get(prefix_in_quant_config, "STATIC")
== "W4A4_DYNAMIC"
)
is_moe_w4a8_dynamic = (
self.quant_description.get(prefix_in_quant_config, "STATIC")
== "W4A8_DYNAMIC"
)
is_moe_w8a8_dynamic = (
self.quant_description.get(prefix_in_quant_config, "STATIC")
== "W8A8_DYNAMIC"
)
if is_moe_w4a4_dynamic:
logger.info_once("Using ModelSlimW4A4Int4MoE")
return ModelSlimW4A4Int4MoE(self)
elif is_moe_w4a8_dynamic:
logger.info_once("Using ModelSlimW4A8Int8MoE")
return ModelSlimW4A8Int8MoE(self)
elif is_moe_w8a8_dynamic:
logger.info_once("Using ModelSlimW8A8Int8MoE")
return ModelSlimW8A8Int8MoE(self)
else:
logger.warning(
f"Unsupported FusedMoe modelslim scheme: "
f"{self.quant_description.get(prefix_in_quant_config.strip())} "
f"in layer: {prefix}"
)
return None
def is_layer_skipped(
self, prefix: str, fused_mapping: Mapping[str, List[str]] = MappingProxyType({})
):
# adapted from vllm.model_executor.layers.quantization.utils.quant_utils.is_layer_skipped
proj_name = prefix.split(".")[-1]
if proj_name in fused_mapping:
shard_prefixes = [
prefix.replace(proj_name, shard_proj_name)
for shard_proj_name in fused_mapping[proj_name]
]
is_skipped = None
for shard_prefix in shard_prefixes:
is_shard_skipped = (
self.quant_description.get(shard_prefix + ".weight", "") == "FLOAT"
)
if is_skipped is None:
is_skipped = is_shard_skipped
elif is_shard_skipped != is_skipped:
raise ValueError(
f"Detected some but not all shards of {prefix} "
"are quantized. All shards of fused layers "
"to have the same precision."
)
else:
is_skipped = self.quant_description.get(prefix + ".weight", "") == "FLOAT"
assert is_skipped is not None
return is_skipped
def get_scaled_act_names(self) -> List[str]:
return []
class ModelSlimLinearMethod(_NPULinearMethodBase):
def __init__(self, quantization_config: ModelSlimConfig):
self.quantization_config = quantization_config
def process_weights_after_loading(self, layer: torch.nn.Module) -> None:
layer.scheme.process_weights_after_loading(layer)
def create_weights(
self,
layer: torch.nn.Module,
input_size_per_partition: int,
output_partition_sizes: List[int],
input_size: int,
output_size: int,
params_dtype: torch.dtype,
**extra_weight_attrs,
):
"""
Use the ModelSlimLinearScheme associated with the layer to create
the necessary parameters for the layer. See LinearMethodBase for param
details
"""
weight_loader = extra_weight_attrs.get("weight_loader")
layer.scheme.create_weights(
layer=layer,
input_size=input_size,
input_size_per_partition=input_size_per_partition,
output_partition_sizes=output_partition_sizes,
output_size=output_size,
params_dtype=params_dtype,
weight_loader=weight_loader,
)
def apply(
self,
layer: torch.nn.Module,
x: torch.Tensor,
bias: Optional[torch.Tensor] = None,
):
"""
Use the output of create_weights and the ModelSlimLinearScheme
associated with the layer to apply the forward pass with the
layer input. See LinearMethodBase for param details
"""
scheme = layer.scheme
if scheme is None:
raise ValueError("A scheme must be defined for each layer")
return scheme.apply_weights(layer, x, bias=bias)
class ModelSlimFusedMoEMethod(FusedMoEMethodBase):
def __init__(self, quantization_config: ModelSlimConfig):
self.quantization_config = quantization_config
def process_weights_after_loading(self, layer: torch.nn.Module) -> None:
layer.scheme.process_weights_after_loading(layer)
def create_weights(
self,
layer: torch.nn.Module,
num_experts: int,
hidden_size: int,
intermediate_size_per_partition: int,
params_dtype: torch.dtype,
**extra_weight_attrs,
):
"""
Use the ModelSlimMoEScheme associated with the layer to create
the necessary parameters for the layer. See FusedMoEMethodBase for param
details
"""
layer.scheme.create_weights(
layer=layer,
num_experts=num_experts,
hidden_size=hidden_size,
intermediate_size_per_partition=intermediate_size_per_partition,
params_dtype=params_dtype,
**extra_weight_attrs,
)
def create_moe_runner(
self, layer: torch.nn.Module, moe_runner_config: MoeRunnerConfig
):
return layer.scheme.create_moe_runner(layer, moe_runner_config)
def apply(
self,
layer: torch.nn.Module,
dispatch_output: StandardDispatchOutput,
) -> CombineInput:
"""
Use the output of create_weights and the ModelSlimMoEScheme
associated with the layer to apply the forward pass with the
layer input. See FusedMoEMethodBase for param details
"""
scheme = layer.scheme
if scheme is None:
raise ValueError("A scheme must be defined for each layer")
return scheme.apply_weights(layer, dispatch_output)
def apply_without_routing_weights(
self,
layer,
hidden_states,
hidden_states_scale,
group_list_type,
group_list,
output_dtype,
):
return layer.scheme.apply_without_routing_weights(
layer,
hidden_states,
hidden_states_scale,
group_list_type,
group_list,
output_dtype,
)