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on
Zero
Running
on
Zero
from typing import * | |
import torch | |
import torch.nn as nn | |
from ...modules.utils import convert_module_to_f16, convert_module_to_f32 | |
from ...modules import sparse as sp | |
from ...modules.transformer import AbsolutePositionEmbedder | |
from ...modules.sparse.transformer import SparseTransformerBlock | |
def block_attn_config(self): | |
""" | |
Return the attention configuration of the model. | |
""" | |
for i in range(self.num_blocks): | |
if self.attn_mode == "shift_window": | |
yield "serialized", self.window_size, 0, (16 * (i % 2),) * 3, sp.SerializeMode.Z_ORDER | |
elif self.attn_mode == "shift_sequence": | |
yield "serialized", self.window_size, self.window_size // 2 * (i % 2), (0, 0, 0), sp.SerializeMode.Z_ORDER | |
elif self.attn_mode == "shift_order": | |
yield "serialized", self.window_size, 0, (0, 0, 0), sp.SerializeModes[i % 4] | |
elif self.attn_mode == "full": | |
yield "full", None, None, None, None | |
elif self.attn_mode == "swin": | |
yield "windowed", self.window_size, None, self.window_size // 2 * (i % 2), None | |
class SparseTransformerBase(nn.Module): | |
""" | |
Sparse Transformer without output layers. | |
Serve as the base class for encoder and decoder. | |
""" | |
def __init__( | |
self, | |
in_channels: int, | |
model_channels: int, | |
num_blocks: int, | |
num_heads: Optional[int] = None, | |
num_head_channels: Optional[int] = 64, | |
mlp_ratio: float = 4.0, | |
attn_mode: Literal["full", "shift_window", "shift_sequence", "shift_order", "swin"] = "full", | |
window_size: Optional[int] = None, | |
pe_mode: Literal["ape", "rope"] = "ape", | |
use_fp16: bool = False, | |
use_checkpoint: bool = False, | |
qk_rms_norm: bool = False, | |
): | |
super().__init__() | |
self.in_channels = in_channels | |
self.model_channels = model_channels | |
self.num_blocks = num_blocks | |
self.window_size = window_size | |
self.num_heads = num_heads or model_channels // num_head_channels | |
self.mlp_ratio = mlp_ratio | |
self.attn_mode = attn_mode | |
self.pe_mode = pe_mode | |
self.use_fp16 = use_fp16 | |
self.use_checkpoint = use_checkpoint | |
self.qk_rms_norm = qk_rms_norm | |
self.dtype = torch.float16 if use_fp16 else torch.float32 | |
if pe_mode == "ape": | |
self.pos_embedder = AbsolutePositionEmbedder(model_channels) | |
self.input_layer = sp.SparseLinear(in_channels, model_channels) | |
self.blocks = nn.ModuleList([ | |
SparseTransformerBlock( | |
model_channels, | |
num_heads=self.num_heads, | |
mlp_ratio=self.mlp_ratio, | |
attn_mode=attn_mode, | |
window_size=window_size, | |
shift_sequence=shift_sequence, | |
shift_window=shift_window, | |
serialize_mode=serialize_mode, | |
use_checkpoint=self.use_checkpoint, | |
use_rope=(pe_mode == "rope"), | |
qk_rms_norm=self.qk_rms_norm, | |
) | |
for attn_mode, window_size, shift_sequence, shift_window, serialize_mode in block_attn_config(self) | |
]) | |
def device(self) -> torch.device: | |
""" | |
Return the device of the model. | |
""" | |
return next(self.parameters()).device | |
def convert_to_fp16(self) -> None: | |
""" | |
Convert the torso of the model to float16. | |
""" | |
self.blocks.apply(convert_module_to_f16) | |
def convert_to_fp32(self) -> None: | |
""" | |
Convert the torso of the model to float32. | |
""" | |
self.blocks.apply(convert_module_to_f32) | |
def initialize_weights(self) -> None: | |
# Initialize transformer layers: | |
def _basic_init(module): | |
if isinstance(module, nn.Linear): | |
torch.nn.init.xavier_uniform_(module.weight) | |
if module.bias is not None: | |
nn.init.constant_(module.bias, 0) | |
self.apply(_basic_init) | |
def forward(self, x: sp.SparseTensor) -> sp.SparseTensor: | |
h = self.input_layer(x) | |
if self.pe_mode == "ape": | |
h = h + self.pos_embedder(x.coords[:, 1:]) | |
h = h.type(self.dtype) | |
for block in self.blocks: | |
h = block(h) | |
return h | |