[Core] Refactor ColumnParallelLinear: remove unused parameter and optimize forward (#31939)

Signed-off-by: maang <maang_h@163.com>

vllm/model_executor/layers/linear.py

@@ -411,10 +411,10 @@ class ReplicatedLinear(LinearBase):
         assert self.quant_method is not None
 
         output = self.quant_method.apply(self, x, bias)
-        output_bias = self.bias if self.skip_bias_add else None
 
         if not self.return_bias:
             return output
+        output_bias = self.bias if self.skip_bias_add else None
         return output, output_bias
 
     def extra_repr(self) -> str:
@@ -444,8 +444,6 @@ class ColumnParallelLinear(LinearBase):
                        skip adding bias but instead return it.
         params_dtype: Data type for the parameters.
         quant_config: Quantization configure.
-        output_sizes: list of output sizes packed into one output, like for QKV
-                       the list would be size 3.
         prefix: The name of the layer in the state dict, including all parents
                         (e.g. model.layers.0.qkv_proj)
         return_bias: If true, return bias together with outputs in forward pass.
@@ -463,7 +461,6 @@ class ColumnParallelLinear(LinearBase):
         skip_bias_add: bool = False,
         params_dtype: torch.dtype | None = None,
         quant_config: QuantizationConfig | None = None,
-        output_sizes: list[int] | None = None,
         prefix: str = "",
         *,
         return_bias: bool = True,
@@ -495,9 +492,6 @@ class ColumnParallelLinear(LinearBase):
         self._maybe_allow_fp8_block_shape_mismatch()
         self.gather_output = gather_output
 
-        if output_sizes is None:
-            output_sizes = [output_size]
-
         assert self.quant_method is not None
         self.quant_method.create_weights(
             layer=self,
@@ -614,9 +608,10 @@ class ColumnParallelLinear(LinearBase):
             output = tensor_model_parallel_all_gather(output_parallel)
         else:
             output = output_parallel
-        output_bias = self.bias if self.skip_bias_add else None
+
         if not self.return_bias:
             return output
+        output_bias = self.bias if self.skip_bias_add else None
         return output, output_bias
 
     def extra_repr(self) -> str:
@@ -1469,10 +1464,9 @@ class RowParallelLinear(LinearBase):
         else:
             output = output_parallel
 
-        output_bias = self.bias if self.skip_bias_add else None
-
         if not self.return_bias:
             return output
+        output_bias = self.bias if self.skip_bias_add else None
         return output, output_bias
 
     def extra_repr(self) -> str: