[platform] add device_control env var

vllm/platforms/cuda.py

@@ -78,6 +78,7 @@ class CudaPlatformBase(Platform):
     device_type: str = "cuda"
     dispatch_key: str = "CUDA"
     ray_device_key: str = "GPU"
+    device_control_env_var: str = "CUDA_VISIBLE_DEVICES"
 
     @classmethod
     def get_device_capability(cls,

vllm/platforms/hpu.py

@@ -20,6 +20,7 @@ class HpuPlatform(Platform):
     device_type: str = "hpu"
     dispatch_key: str = "HPU"
     ray_device_key: str = "HPU"
+    device_control_env_var: str = "HABANA_VISIBLE_MODULES"
 
     @classmethod
     def get_attn_backend_cls(cls, selected_backend: _Backend, head_size: int,

vllm/platforms/interface.py

@@ -78,20 +78,30 @@ class Platform:
     _enum: PlatformEnum
     device_name: str
     device_type: str
+
     # available dispatch keys:
     # check https://github.com/pytorch/pytorch/blob/313dac6c1ca0fa0cde32477509cce32089f8532a/torchgen/model.py#L134 # noqa
     # use "CPU" as a fallback for platforms not registered in PyTorch
     dispatch_key: str = "CPU"
+
     # available ray device keys:
     # https://github.com/ray-project/ray/blob/10ba5adadcc49c60af2c358a33bb943fb491a171/python/ray/_private/ray_constants.py#L438 # noqa
     # empty string means the device does not support ray
     ray_device_key: str = ""
+
+    # platform-agnostic way to specify the device control environment variable,
+    # .e.g. CUDA_VISIBLE_DEVICES for CUDA.
+    # hint: search for "get_visible_accelerator_ids_env_var" in
+    # https://github.com/ray-project/ray/tree/master/python/ray/_private/accelerators # noqa
+    device_control_env_var: str = "VLLM_DEVICE_CONTROL_ENV_VAR_PLACEHOLDER"
+
     # The torch.compile backend for compiling simple and
     # standalone functions. The default value is "inductor" to keep
     # the same behavior as PyTorch.
     # NOTE: for the forward part of the model, vLLM has another separate
     # compilation strategy.
     simple_compile_backend: str = "inductor"
+
     supported_quantization: list[str] = []
 
     def is_cuda(self) -> bool:

vllm/platforms/neuron.py

@@ -18,6 +18,7 @@ class NeuronPlatform(Platform):
     device_type: str = "neuron"
     ray_device_key: str = "neuron_cores"
     supported_quantization: list[str] = ["neuron_quant"]
+    device_control_env_var: str = "NEURON_RT_VISIBLE_CORES"
 
     @classmethod
     def get_device_name(cls, device_id: int = 0) -> str:

vllm/platforms/rocm.py

@@ -65,6 +65,8 @@ class RocmPlatform(Platform):
     device_type: str = "cuda"
     dispatch_key: str = "CUDA"
     ray_device_key: str = "GPU"
+    # rocm shares the same device control env var as CUDA
+    device_control_env_var: str = "CUDA_VISIBLE_DEVICES"
 
     supported_quantization: list[str] = [
         "awq", "gptq", "fp8", "compressed_tensors", "compressed-tensors",

vllm/platforms/tpu.py

@@ -20,6 +20,7 @@ class TpuPlatform(Platform):
     device_type: str = "tpu"
     dispatch_key: str = "XLA"
     ray_device_key: str = "TPU"
+    device_control_env_var: str = "TPU_VISIBLE_CHIPS"
 
     supported_quantization: list[str] = [
         "tpu_int8", "compressed-tensors", "compressed_tensors"

vllm/platforms/xpu.py

@@ -22,6 +22,7 @@ class XPUPlatform(Platform):
     # Intel XPU's device key is "GPU" for Ray.
     # see https://github.com/ray-project/ray/blob/6a5eb5865eeb9ccf058a79b44f107e327e360673/python/ray/_private/accelerators/intel_gpu.py#L20 # noqa: E501
     ray_device_key: str = "GPU"
+    device_control_env_var: str = "ONEAPI_DEVICE_SELECTOR"
 
     @classmethod
     def get_attn_backend_cls(cls, selected_backend: _Backend, head_size: int,