Repository: huggingface/transformers
Pull request: prevent creating a view/leaf param for low rank optimizers w FSDP

# What does this PR do?
Currently, low rank optimizers like Apollo can't be used with FSDP with the error below which is caused by copying the param, causing a view/leaf of the parameter. This PR fixes that and allows apollo_adamw optimizer to be used with FSDP(1)

```
[rank0]:   File "/root/miniconda3/envs/py3.11/lib/python3.11/site-packages/transformers/trainer.py", line 1246, in create_optimizer
[rank0]:     self.optimizer = optimizer_cls(optimizer_grouped_parameters, **optimizer_kwargs)       
[rank0]:                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
[rank0]:   File "/root/miniconda3/envs/py3.11/lib/python3.11/site-packages/torch/_dynamo/eval_frame.py", line 745, in _fn
[rank0]:     return fn(*args, **kwargs)                                                                                       
[rank0]:            ^^^^^^^^^^^^^^^^^^^                    
[rank0]:   File "/root/miniconda3/envs/py3.11/lib/python3.11/site-packages/apollo_torch/apollo.py", line 74, in __init__
[rank0]:     super().__init__(params, defaults)                                                                               
[rank0]:   File "/root/miniconda3/envs/py3.11/lib/python3.11/site-packages/torch/optim/optimizer.py", line 377, in __init__
[rank0]:     self.add_param_group(cast(dict, param_group))
[rank0]:   File "/root/miniconda3/envs/py3.11/lib/python3.11/site-packages/torch/_compile.py", line 32, in inner
[rank0]:     return disable_fn(*args, **kwargs)
[rank0]:            ^^^^^^^^^^^^^^^^^^^^^^^^^^^
[rank0]:   File "/root/miniconda3/envs/py3.11/lib/python3.11/site-packages/torch/_dynamo/eval_frame.py", line 745, in _fn
[rank0]:     return fn(*args, **kwargs)  
[rank0]:            ^^^^^^^^^^^^^^^^^^^  
[rank0]:   File "/root/miniconda3/envs/py3.11/lib/python3.11/site-packages/torch/optim/optimizer.py", line 1062, in add_param_group
[rank0]:     param.is_leaf or param.retains_grad
[rank0]:     ^^^^^^^^^^^^^                                                                                                    
[rank0]: RuntimeError: Output 0 of ViewBackward0 is a view and its base or another view of its base has been modified inplace. This view is the output of a function that returns multiple views. Such functions do not allow the output views to be modified
```

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Fixes # (issue)


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## Who can review?

@SunMarc @ArthurZucker 
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Changed files:
filename: src/transformers/trainer.py
patch: @@ -1363,7 +1363,6 @@ def setup_low_rank_optimizer(
                 and args.optim_target_modules.replace("_", "-") == "all-linear"
             )
 
-            target_params = []
             target_params_names = []
             for module_name, module in model.named_modules():
                 target_module_exists, is_regex = check_target_module_exists(
@@ -1380,12 +1379,12 @@ def setup_low_rank_optimizer(
                 if not target_module_exists and not all_linear:
                     continue
 
-                target_params.append(module.weight)
                 target_params_names.append(module_name + ".weight")
 
-            if len(target_params) == 0:
+            if len(target_params_names) == 0:
                 raise ValueError(f"No target modules found for {optimizer_name} ({args.optim_target_modules}).")
 
+            target_params = [p for n, p in model.named_parameters() if n in target_params_names]
             non_target_params = [p for n, p in model.named_parameters() if n not in target_params_names]
             optim_kwargs.update(optim_args)