[v1] add models & accelerator (#9579)

src/llamafactory/v1/accelerator/helper.py

@@ -0,0 +1,52 @@
+# Copyright 2025 the LlamaFactory team.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from functools import lru_cache
+
+import torch
+
+
+def get_current_accelerator(check_available: bool = True):
+    """Get current accelerator.
+
+    Note: this api requires torch>=2.7.0, 2.6 or lower will get an AttributeError or RuntimeError
+    """
+    if not hasattr(torch, "accelerator"):
+        raise RuntimeError("torch.accelerator is not available, please upgrade torch to 2.7.0 or higher.")
+
+    accelerator = torch.accelerator.current_accelerator(check_available=check_available)
+    if accelerator is None:
+        return torch.device("cpu")
+
+    return accelerator
+
+
+@lru_cache
+def is_torch_npu_available():
+    return get_current_accelerator().type == "npu"
+
+
+@lru_cache
+def is_torch_cuda_available():
+    return get_current_accelerator().type == "cuda"
+
+
+@lru_cache
+def is_torch_xpu_available():
+    return get_current_accelerator().type == "xpu"
+
+
+@lru_cache
+def is_torch_mps_available():
+    return get_current_accelerator().type == "mps"