Source code for nni.compression.torch.utils.mask_conflict

# Copyright (c) Microsoft Corporation.
# Licensed under the MIT license.
import os
import logging
import torch
import numpy as np
from .shape_dependency import ChannelDependency, GroupDependency, CatPaddingDependency
# logging.basicConfig(level = logging.DEBUG)
_logger = logging.getLogger('FixMaskConflict')

def fix_mask_conflict(masks, model=None, dummy_input=None, traced=None):
    """
    MaskConflict fix the mask conflict for the channel dependencies
    and group dependency.

    Parameters
    ----------
    masks : dict/str
        A dict object that stores the masks or the path of the mask file
    model : torch.nn.Module
        model to fix the mask conflict
    dummy_input : torch.Tensor
        input example to trace the model
    traced : torch._C.torch.jit.TopLevelTracedModule
        the traced model of the target model, is this parameter is not None,
        we donnot use the model and dummpy_input to get the trace graph.
    """
    if isinstance(masks, str):
        # if the input is the path of the mask_file
        assert os.path.exists(masks)
        masks = torch.load(masks)
    # if the user uses the model and dummy_input to trace the model, we
    # should get the traced model handly, so that, we only trace the
    # model once, GroupMaskConflict and ChannelMaskConflict will reuse
    # this traced model.
    if traced is None:
        assert model is not None and dummy_input is not None
        with torch.onnx.set_training(model, False):
            # We need to trace the model in this way, else it will have problems
            traced = torch.jit.trace(model, dummy_input)

    fix_group_mask = GroupMaskConflict(masks, model, dummy_input, traced)
    masks = fix_group_mask.fix_mask()
    fix_channel_mask = ChannelMaskConflict(masks, model, dummy_input, traced)
    masks = fix_channel_mask.fix_mask()
    padding_cat_mask = CatMaskPadding(masks, model, dummy_input, traced)
    masks = padding_cat_mask.fix_mask()
    return masks

class MaskFix:
    def __init__(self, masks, model=None, dummy_input=None, traced=None):
        # check if the parameters are valid
        parameter_valid = False
        if traced is not None:
            parameter_valid = True
        elif (model is not None) and (dummy_input is not None):
            parameter_valid = True
        if not parameter_valid:
            raise Exception('The input parameters is invalid!')
        self.model = model
        self.dummy_input = dummy_input
        self.traced = traced
        self.masks = masks

    def fix_mask(self):
        raise NotImplementedError

    def export(self, path):
        """
        Export the masks after fixing the conflict to file.
        """
        torch.save(self.masks, path)

[docs]class CatMaskPadding(MaskFix): def __init__(self, masks, model, dummy_input=None, traced=None): """ CatMaskPadding find the layers whose output tensor is passed to the same cat operation. The cat operation concatnates the masks of the input tensors as the output mask, so when some of the input layers of the cat operation are not pruned, we still need to pass the masks of these non-pruned layers(the mask are all ones) to the cat operation to ensure the shape of the output mask is right. Parameters ---------- masks : dict a dict object that stores the masks model : torch.nn.Module model to fix the mask conflict dummy_input : torch.Tensor input example to trace the model traced : torch._C.torch.jit.TopLevelTracedModule the traced model of the target model, is this parameter is not None, we donnot use the model and dummpy_input to get the trace graph. """ super(CatMaskPadding, self).__init__(masks, model, dummy_input, traced) def fix_mask(self): cat_padding_depen = CatPaddingDependency(self.model, self.dummy_input, self.traced) name_to_module = {} for name, module in self.model.named_modules(): name_to_module[name] = module depen = cat_padding_depen.dependency_sets for layers in depen: device = None count = 0 for layer in layers: if layer in self.masks: count += 1 if device is None: device = self.masks[layer]['weight'].device if count == 0: # no layer is pruned continue elif count == len(layers): # all the layers have been pruned continue # pad the mask for the non-pruned layers for layer in layers: if layer in self.masks: continue module = name_to_module[layer] w_shape = module.weight.data.size() w_mask = torch.ones(w_shape).to(device) b_mask = None if hasattr(module, 'bias') and module.bias is not None: # module.bias may be None b_shape = module.bias.data.size() b_mask = torch.ones(b_shape).to(device) self.masks[layer] = {'weight':w_mask, 'bias':b_mask} return self.masks
[docs]class GroupMaskConflict(MaskFix): def __init__(self, masks, model=None, dummy_input=None, traced=None): """ GroupMaskConflict fix the mask conflict between the layers that has group dependecy with each other. Parameters ---------- masks : dict a dict object that stores the masks model : torch.nn.Module model to fix the mask conflict dummy_input : torch.Tensor input example to trace the model traced : torch._C.torch.jit.TopLevelTracedModule the traced model of the target model, is this parameter is not None, we donnot use the model and dummpy_input to get the trace graph. """ super(GroupMaskConflict, self).__init__(masks, model, dummy_input, traced)
[docs] def fix_mask(self): """ Fix the mask conflict before the mask inference for the layers that has group dependencies. This function should be called before the mask inference of the 'speedup' module. """ group_depen = GroupDependency(self.model, self.dummy_input, self.traced) depens = group_depen.dependency _logger.info(depens) for layername in depens: group = depens[layername] if layername not in self.masks: # this layer not pruned continue w_mask = self.masks[layername]['weight'] shape = w_mask.size() count = np.prod(shape[1:]) all_ones = (w_mask.flatten(1).sum(-1) == count).nonzero().squeeze(1).tolist() all_zeros = (w_mask.flatten(1).sum(-1) == 0).nonzero().squeeze(1).tolist() if len(all_ones) + len(all_zeros) < w_mask.size(0): # In fine-grained pruning, skip this layer _logger.info('Layers %s using fine-grained pruning', layername) continue assert shape[0] % group == 0 # Find the number of masked filter for each group (mini_masked). # Because we have to keep the pruned filter can still # be divided into the same number of groups, so we only can # prune mini_masked filters for each group. step = shape[0] / group group_masked = [] for i in range(group): _start = step * i _end = step * (i+1) _tmp_list = list(filter(lambda x: _start <= x and x < _end, all_zeros)) group_masked.append(_tmp_list) mini_masked = min([len(x) for x in group_masked]) for gm in group_masked: for i in range(mini_masked, len(gm)): # To keep the output channel number still being divisible to # groups, we set the masks of following filters to be zero. pos = gm[i] self.masks[layername]['weight'][pos] = torch.ones(shape[1:]) if hasattr(self.masks[layername], 'bias'): self.masks[layername]['bias'][pos] = 1 return self.masks
[docs]class ChannelMaskConflict(MaskFix): def __init__(self, masks, model=None, dummy_input=None, traced=None): """ ChannelMaskConflict fix the mask conflict between the layers that has channel dependecy with each other. Parameters ---------- masks : dict a dict object that stores the masks model : torch.nn.Module model to fix the mask conflict dummy_input : torch.Tensor input example to trace the model graph : torch._C.torch.jit.TopLevelTracedModule the traced graph of the target model, is this parameter is not None, we donnot use the model and dummpy_input to get the trace graph. """ super(ChannelMaskConflict, self).__init__(masks, model, dummy_input, traced)
[docs] def fix_mask(self): """ Fix the mask conflict before the mask inference for the layers that has shape dependencies. This function should be called before the mask inference of the 'speedup' module. """ channel_depen = ChannelDependency(self.model, self.dummy_input, self.traced) depen_sets = channel_depen.dependency_sets for dset in depen_sets: if len(dset) == 1: # This layer has no channel dependency with other layers continue channel_remain = set() fine_grained = False out_channels = None # A flag that represents if all the layers in # the dependency set are pruned all_pruned = True for name in dset: if name not in self.masks: # this layer is not pruned all_pruned = False continue w_mask = self.masks[name]['weight'] if out_channels is None: out_channels = w_mask.size(0) shape = w_mask.size() count = np.prod(shape[1:]) all_ones = (w_mask.flatten(1).sum(-1) == count).nonzero().squeeze(1).tolist() all_zeros = (w_mask.flatten(1).sum(-1) == 0).nonzero().squeeze(1).tolist() if len(all_ones) + len(all_zeros) < w_mask.size(0): # In fine-grained pruning, there is no need to check # the shape conflict _logger.info('Layers %s using fine-grained pruning', ','.join(dset)) fine_grained = True break channel_remain.update(all_ones) _logger.debug('Layer: %s ', name) _logger.debug('Original pruned filters: %s', str(all_zeros)) # Update the masks for the layers in the dependency set if fine_grained or out_channels is None: # if use the fine-grained pruner or all the layers in # this dependency set are not pruned continue if not all_pruned: # if some layer are not pruned at all # then all the layers in this dependency set # cannot be pruned due to the shape dependency. channel_remain.update(range(out_channels)) ori_channels = 0 for name in dset: if name not in self.masks: # this layer is not pruned at all # in this case, all_pruned is False # and the other layers in the same dset # will not be pruned either. continue mask = self.masks[name] w_shape = mask['weight'].size() ori_channels = w_shape[0] for i in channel_remain: mask['weight'][i] = torch.ones(w_shape[1:]) if hasattr(mask, 'bias'): mask['bias'][i] = 1 _logger.info(','.join(dset)) _logger.info('Pruned Filters after fixing conflict:') pruned_filters = set(list(range(ori_channels)))-channel_remain _logger.info(str(sorted(pruned_filters))) return self.masks