[bugfix] add supports_v1 platform interface (#15417)

Signed-off-by: Joe Runde <Joseph.Runde@ibm.com>

vllm/engine/arg_utils.py

@@ -1666,9 +1666,8 @@ class EngineArgs:
             _raise_or_fallback(feature_name=name, recommend_to_remove=True)
             return False
 
-        # No support for device type other than CUDA, AMD (experiemntal) or
-        # TPU (experimental) so far.
-        if not (current_platform.is_cuda_alike() or current_platform.is_tpu()):
+        # Platforms must decide if they can support v1 for this model
+        if not current_platform.supports_v1(model_config=model_config):
             _raise_or_fallback(
                 feature_name=f"device type={current_platform.device_type}",
                 recommend_to_remove=False)

vllm/platforms/cuda.py

@@ -20,8 +20,9 @@ from vllm.utils import import_pynvml
 from .interface import DeviceCapability, Platform, PlatformEnum, _Backend
 
 if TYPE_CHECKING:
-    from vllm.config import VllmConfig
+    from vllm.config import ModelConfig, VllmConfig
 else:
+    ModelConfig = None
     VllmConfig = None
 
 logger = init_logger(__name__)
@@ -303,6 +304,10 @@ class CudaPlatformBase(Platform):
     def supports_fp8(cls) -> bool:
         return cls.has_device_capability(89)
 
+    @classmethod
+    def supports_v1(cls, model_config: ModelConfig) -> bool:
+        return True
+
 
 # NVML utils
 # Note that NVML is not affected by `CUDA_VISIBLE_DEVICES`,

vllm/platforms/interface.py

@@ -12,9 +12,10 @@ import torch
 from vllm.logger import init_logger
 
 if TYPE_CHECKING:
-    from vllm.config import VllmConfig
+    from vllm.config import ModelConfig, VllmConfig
     from vllm.utils import FlexibleArgumentParser
 else:
+    ModelConfig = None
     VllmConfig = None
     FlexibleArgumentParser = None
 
@@ -371,6 +372,13 @@ class Platform:
                 or parallel_config.distributed_executor_backend
                 == "external_launcher")
 
+    @classmethod
+    def supports_v1(cls, model_config: ModelConfig) -> bool:
+        """Returns whether the current platform can support v1 for the supplied
+        model configuration.
+        """
+        return False
+
 
 class UnspecifiedPlatform(Platform):
     _enum = PlatformEnum.UNSPECIFIED

vllm/platforms/rocm.py

@@ -12,8 +12,9 @@ from vllm.logger import init_logger
 from .interface import DeviceCapability, Platform, PlatformEnum, _Backend
 
 if TYPE_CHECKING:
-    from vllm.config import VllmConfig
+    from vllm.config import ModelConfig, VllmConfig
 else:
+    ModelConfig = None
     VllmConfig = None
 
 logger = init_logger(__name__)
@@ -249,3 +250,8 @@ class RocmPlatform(Platform):
             return torch.float8_e4m3fnuz
         else:
             return torch.float8_e4m3fn
+
+    @classmethod
+    def supports_v1(cls, model_config: ModelConfig) -> bool:
+        # V1 support on AMD gpus is experimental
+        return True

vllm/platforms/tpu.py

@@ -10,8 +10,9 @@ from vllm.logger import init_logger
 from .interface import Platform, PlatformEnum, _Backend
 
 if TYPE_CHECKING:
-    from vllm.config import VllmConfig
+    from vllm.config import ModelConfig, VllmConfig
 else:
+    ModelConfig = None
     VllmConfig = None
 
 logger = init_logger(__name__)
@@ -127,3 +128,8 @@ class TpuPlatform(Platform):
     @classmethod
     def use_all_gather(cls) -> bool:
         return True
+
+    @classmethod
+    def supports_v1(cls, model_config: ModelConfig) -> bool:
+        # V1 support on TPU is experimental
+        return True