Repository: huggingface/transformers
Pull request: fix ndim check of device_mesh for TP

# What does this PR do?

This check is inverted. When I passed in a TP device mesh that's a single ndim, I hit this assertion. The TODO implies that multi-dim isn't supported yet, as well as the error message indicates that the check should be the inverse of the current check.

@SunMarc @S1ro1 

Fixes # (issue)


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Changed files:
filename: src/transformers/modeling_utils.py
patch: @@ -4522,7 +4522,7 @@ def from_pretrained(
                 tp_plan, device_map, device_mesh = initialize_tensor_parallelism(tp_plan, tp_size=None)
             else:
                 # TODO: make device_mesh support multiple dimensions
-                if device_mesh.ndim == 1:
+                if device_mesh.ndim != 1:
                     raise ValueError("device_mesh must be 1 dimensional and will be used for TP")
                 device_map = torch.device(device_mesh.device_type, int(os.environ["LOCAL_RANK"]))