under test, not sure no errors

vllm/platforms/cpu.py

@@ -0,0 +1,20 @@
+import psutil
+import torch
+
+from .interface import Platform, PlatformEnum
+
+
+class CpuPlatform(Platform):
+    _enum = PlatformEnum.CPU
+
+    @classmethod
+    def get_device_name(cls, device_id: int = 0) -> str:
+        return "cpu"
+
+    @classmethod
+    def get_device_total_memory(cls, device_id: int = 0) -> int:
+        return psutil.virtual_memory().total
+
+    @classmethod
+    def inference_mode(cls):
+        return torch.no_grad()