[exmaple] add vit missing functions (#2154)

examples/images/vit/test_vit.py

+import os
+import random
 from functools import partial
 
+import numpy as np
 import pytest
 import torch
 import torch.multiprocessing as mp
 from torch.nn.parallel import DistributedDataParallel as DDP
-from utils.util import set_seed, tensor_equal, tensor_shard_equal
 from vit import get_training_components
 
 import colossalai
+from colossalai.context import ParallelMode
 from colossalai.context.parallel_mode import ParallelMode
 from colossalai.core import global_context as gpc
 from colossalai.nn.parallel.data_parallel import ColoDDP
-from colossalai.tensor import ColoParameter, ComputePattern, ComputeSpec, DistSpecManager, ProcessGroup, ShardSpec
+from colossalai.tensor import ComputePattern, ComputeSpec, DistSpecManager, ProcessGroup, ShardSpec
 from colossalai.testing import rerun_if_address_is_in_use
 from colossalai.utils import free_port
 from colossalai.utils.cuda import get_current_device
 from colossalai.utils.model.colo_init_context import ColoInitContext
 
 
+def set_seed(seed):
+    random.seed(seed)
+    os.environ['PYTHONHASHSEED'] = str(seed)
+    np.random.seed(seed)
+    torch.manual_seed(seed)
+    torch.cuda.manual_seed(seed)
+    torch.backends.cudnn.deterministic = True
+
+
+def tensor_equal(A, B):
+    return torch.allclose(A, B, rtol=1e-3, atol=1e-1)
+
+
+def tensor_shard_equal(tensor: torch.Tensor, shard: torch.Tensor):
+    assert tensor.ndim == shard.ndim
+    if tensor.shape == shard.shape:
+        return tensor_equal(tensor, shard)
+    else:
+        dims_not_eq = torch.nonzero(torch.tensor(tensor.shape) != torch.tensor(shard.shape))
+        if dims_not_eq.numel() == 1:
+            # 1D shard
+            dim = dims_not_eq.item()
+            world_size = gpc.get_world_size(ParallelMode.PARALLEL_1D)
+            rank = gpc.get_local_rank(ParallelMode.PARALLEL_1D)
+            return tensor_equal(tensor.chunk(world_size, dim)[rank], shard)
+        else:
+            raise
+
+
 # Only for all Linear, it's 1d_row split because Linear will be transposed when calculating.
 # But for other layers, it's 1d_col split.
 # Layernorm is not supported for now.

examples/images/vit/vit.py

+from abc import ABC, abstractmethod
+
 import torch
 import torch.nn as nn
-from utils.dummy_data_generator import DummyDataGenerator
+from transformers import ViTConfig, ViTForImageClassification
 
 from colossalai.utils.cuda import get_current_device
-from transformers import ViTConfig, ViTForImageClassification
+
+
+class DummyDataGenerator(ABC):
+
+    def __init__(self, length=10):
+        self.length = length
+
+    @abstractmethod
+    def generate(self):
+        pass
+
+    def __iter__(self):
+        self.step = 0
+        return self
+
+    def __next__(self):
+        if self.step < self.length:
+            self.step += 1
+            return self.generate()
+        else:
+            raise StopIteration
+
+    def __len__(self):
+        return self.length
 
 
 class DummyDataLoader(DummyDataGenerator):