[gpt-oss] Add gpt-oss bf16 support

vllm/model_executor/layers/quantization/base_config.py

@@ -0,0 +1,154 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
+
+import inspect
+from abc import ABC, abstractmethod
+from typing import TYPE_CHECKING, Any, Optional
+
+import torch
+from torch import nn
+
+if TYPE_CHECKING:
+    from vllm.model_executor.layers.quantization import QuantizationMethods
+else:
+    QuantizationMethods = str
+
+
+class QuantizeMethodBase(ABC):
+    """Base class for different quantized methods."""
+
+    @abstractmethod
+    def create_weights(self, layer: torch.nn.Module, *weight_args,
+                       **extra_weight_attrs):
+        """Create weights for a layer.
+
+        The weights will be set as attributes of the layer."""
+        raise NotImplementedError
+
+    @abstractmethod
+    def apply(self, layer: torch.nn.Module, *args, **kwargs) -> torch.Tensor:
+        """Apply the weights in layer to the input tensor.
+
+        Expects create_weights to have been called before on the layer."""
+        raise NotImplementedError
+
+    # Not required functions
+    def embedding(self, layer: torch.nn.Module, *args,
+                  **kwargs) -> torch.Tensor:
+        """Gather embeddings in the layer based on indices in the input tensor.
+
+        Expects create_weights to have been called before on the layer."""
+        raise NotImplementedError
+
+    def process_weights_after_loading(self, layer: nn.Module) -> None:
+        """Process the weight after loading.
+
+        This can be used for example, to transpose weights for computation.
+        """
+        return
+
+
+def method_has_implemented_embedding(
+        method_class: type[QuantizeMethodBase]) -> bool:
+    """
+    Not all quant methods have embedding implemented, so we need to check that
+    it exists for our given method. We check this by making sure the function
+    has been changed from the base implementation.
+    """
+    base_embedding = inspect.getattr_static(QuantizeMethodBase, "embedding",
+                                            None)
+    class_embedding = inspect.getattr_static(method_class, "embedding", None)
+
+    return (class_embedding is not None
+            and class_embedding is not base_embedding)
+
+
+class QuantizationConfig(ABC):
+    """Base class for quantization configs."""
+
+    def __init__(self):
+        super().__init__()
+        # mapping is updated by models as they initialize
+        self.packed_modules_mapping: dict[str, list[str]] = dict()
+
+    @abstractmethod
+    def get_name(self) -> QuantizationMethods:
+        """Name of the quantization method."""
+        raise NotImplementedError
+
+    @abstractmethod
+    def get_supported_act_dtypes(self) -> list[torch.dtype]:
+        """List of supported activation dtypes."""
+        raise NotImplementedError
+
+    @classmethod
+    @abstractmethod
+    def get_min_capability(cls) -> int:
+        """Minimum GPU capability to support the quantization method.
+
+        E.g., 70 for Volta, 75 for Turing, 80 for Ampere.
+        This requirement is due to the custom CUDA kernels used by the
+        quantization method.
+        """
+        raise NotImplementedError
+
+    @staticmethod
+    @abstractmethod
+    def get_config_filenames() -> list[str]:
+        """List of filenames to search for in the model directory."""
+        raise NotImplementedError
+
+    @classmethod
+    @abstractmethod
+    def from_config(cls, config: dict[str, Any]) -> "QuantizationConfig":
+        """Create a config class from the model's quantization config."""
+        raise NotImplementedError
+
+    @classmethod
+    def override_quantization_method(
+            cls, hf_quant_cfg, user_quant) -> Optional[QuantizationMethods]:
+        """
+           Detects if this quantization method can support a given checkpoint
+           format by overriding the user specified quantization method -- 
+           this method should only be overwritten by subclasses in exceptional 
+           circumstances
+        """
+        if(user_quant != None):
+            return user_quant
+        else:
+            return hf_quant_cfg["quant_method"]
+
+    @staticmethod
+    def get_from_keys(config: dict[str, Any], keys: list[str]) -> Any:
+        """Get a value from the model's quantization config."""
+        for key in keys:
+            if key in config:
+                return config[key]
+        raise ValueError(f"Cannot find any of {keys} in the model's "
+                         "quantization config.")
+
+    @staticmethod
+    def get_from_keys_or(config: dict[str, Any], keys: list[str],
+                         default: Any) -> Any:
+        """Get a optional value from the model's quantization config."""
+        try:
+            return QuantizationConfig.get_from_keys(config, keys)
+        except ValueError:
+            return default
+
+    @abstractmethod
+    def get_quant_method(self, layer: torch.nn.Module,
+                         prefix: str) -> Optional[QuantizeMethodBase]:
+        """Get the quantize method to use for the quantized layer.
+        
+        Args:
+            layer: The layer for the quant method.
+            prefix: The full name of the layer in the state dict
+        Returns:
+            The quantize method. None if the given layer doesn't support quant
+            method.
+        """
+        raise NotImplementedError
+
+    def get_cache_scale(self, name: str) -> Optional[str]:
+        return None