ColossalAI/colossalai/moe/loss.py

79 lines
3.0 KiB
Python

import torch.nn as nn
from torch.nn.modules.loss import _Loss
from colossalai.moe.manager import MOE_MANAGER
class MoeCrossEntropyLoss(_Loss):
r"""torch.nn.CrossEntropyLoss added with auxiliary loss.
Args:
input (:class:`torch.tensor`): Predicted unnormalized scores (often referred to as logits).
target (:class:`torch.tensor`): Ground truth class indices or class probabilities.
aux_weight (float, optional): Weight of auxiliary loss in total loss.Defaults 0.01.
The ``args`` and ``kwargs`` should include parameters below:
::
weight (Tensor, optional)
size_average (bool, optional)
ignore_index (int, optional)
reduce (bool, optional)
reduction (str, optional)
label_smoothing (float, optional)
More details about ``args``, ``kwargs`` and ``torch.nn.functional.cross_entropy`` could be found in
`Cross_entropy <https://pytorch.org/docs/stable/generated/torch.nn.functional.cross_entropy.html#torch.nn.functional.cross_entropy>`_.
"""
def __init__(self, aux_weight: float = 0.01, *args, **kwargs):
super().__init__()
self.loss = nn.CrossEntropyLoss(*args, **kwargs)
self.aux_weight = aux_weight
def forward(self, *args):
"""
The ``args`` should at least include parameters below:
::
input (:class:`torch.tensor`): Predicted unnormalized scores (often referred to as logits).
target (:class:`torch.tensor`): Ground truth class indices or class probabilities.
More details about ``args``, ``kwargs`` and ``torch.nn.functional.cross_entropy`` could be found in
`Cross_entropy <https://pytorch.org/docs/stable/generated/torch.nn.functional.cross_entropy.html#torch.nn.functional.cross_entropy>`_.
"""
main_loss = self.loss(*args)
aux_loss = MOE_MANAGER.get_loss()
return main_loss + self.aux_weight * aux_loss
class MoeLoss(_Loss):
"""A wrapper class for any loss module to add with auxiliary loss.
Args:
aux_weight (float): Weight of auxiliary loss in total loss.
loss_fn (``Callable``): Loss function.
args (list): Args in loss function.
kwargs (dict): Kwargs in loss function
"""
def __init__(self, aux_weight: float, loss_fn, *args, **kwargs):
super().__init__()
self.loss_fn = loss_fn(*args, **kwargs)
self.aux_weight = aux_weight
def forward(self, *args, **kwargs):
"""
The ``args`` and ``kwargs`` should at least include parameters below:
::
input (:class:`torch.tensor`): Predicted unnormalized scores (often referred to as logits).
target (:class:`torch.tensor`): Ground truth class indices or class probabilities.
Note:
The ``args`` and ``kwargs`` may include different parameters varying with different loss function.
"""
main_loss = self.loss_fn(*args, **kwargs)
aux_loss = MOE_MANAGER.get_loss()
return main_loss + self.aux_weight * aux_loss