Remove unused kwargs from model definitions (#13555)

vllm/model_executor/layers/mamba/mamba_mixer.py

@@ -7,6 +7,7 @@ from torch.nn.parameter import Parameter
 from vllm.attention.backends.abstract import AttentionMetadata
 from vllm.distributed.parallel_state import (
     get_tensor_model_parallel_rank, get_tensor_model_parallel_world_size)
+from vllm.forward_context import get_forward_context
 from vllm.model_executor.custom_op import CustomOp
 from vllm.model_executor.layers.layernorm import RMSNorm
 from vllm.model_executor.layers.linear import (ColumnParallelLinear,
@@ -130,14 +131,14 @@ class MambaMixer(CustomOp):
         ) if use_rms_norm else None
 
     def forward_native(self, hidden_states: torch.Tensor,
-                       attn_metadata: AttentionMetadata,
                        conv_state: torch.Tensor, ssm_state: torch.Tensor):
         pass
 
     def forward_cuda(self, hidden_states: torch.Tensor,
-                     attn_metadata: AttentionMetadata,
                      mamba_cache_params: MambaCacheParams):
 
+        attn_metadata: AttentionMetadata = get_forward_context().attn_metadata
+
         # 1. Gated MLP's linear projection
         projected_states = self.in_proj(hidden_states)[0].transpose(-2, -1)
         hidden_states, gate = projected_states.chunk(2, dim=-2)