torch.nn.modules.module.register_module_full_backward_pre_hook

torch.nn.modules.module.register_module_full_backward_pre_hook(hook)

Register a backward pre-hook common to all the modules.

Warning

This adds global state to the nn.module module and it is only intended for debugging/profiling purposes.

The hook will be called every time the gradients for the module are computed. The hook should have the following signature:

hook(module, grad_output) -> Tensor or None

The grad_output is a tuple. The hook should not modify its arguments, but it can optionally return a new gradient with respect to the output that will be used in place of grad_output in subsequent computations. Entries in grad_output will be None for all non-Tensor arguments.

For technical reasons, when this hook is applied to a Module, its forward function will receive a view of each Tensor passed to the Module. Similarly the caller will receive a view of each Tensor returned by the Module’s forward function.

Global hooks are called before hooks registered with register_backward_pre_hook

Returns

a handle that can be used to remove the added hook by calling handle.remove()

Return type

torch.utils.hooks.RemovableHandle