Spaces:
Running
on
Zero
Running
on
Zero
# Copyright (c) Meta Platforms, Inc. and affiliates. | |
# | |
# This source code is licensed under the Apache License, Version 2.0 | |
# found in the LICENSE file in the root directory of this source tree. | |
# References: | |
# https://github.com/facebookresearch/dino/blob/master/vision_transformer.py | |
# https://github.com/rwightman/pytorch-image-models/tree/master/timm/models/vision_transformer.py | |
import logging | |
import os | |
import warnings | |
from torch import unbind | |
#from xformers.ops import memory_efficient_attention | |
from torch import Tensor | |
from torch import nn | |
import torch.nn.functional as F | |
XFORMERS_AVAILABLE = False | |
class Attention(nn.Module): | |
def __init__( | |
self, | |
dim: int, | |
num_heads: int = 8, | |
qkv_bias: bool = True, | |
proj_bias: bool = True, | |
attn_drop: float = 0.0, | |
proj_drop: float = 0.0, | |
norm_layer: nn.Module = nn.LayerNorm, | |
qk_norm: bool = False, | |
fused_attn: bool = True, # use F.scaled_dot_product_attention or not | |
rope=None, | |
) -> None: | |
super().__init__() | |
assert dim % num_heads == 0, "dim should be divisible by num_heads" | |
self.num_heads = num_heads | |
self.head_dim = dim // num_heads | |
self.scale = self.head_dim**-0.5 | |
self.fused_attn = fused_attn | |
self.qkv = nn.Linear(dim, dim * 3, bias=qkv_bias) | |
self.q_norm = norm_layer(self.head_dim) if qk_norm else nn.Identity() | |
self.k_norm = norm_layer(self.head_dim) if qk_norm else nn.Identity() | |
self.attn_drop = nn.Dropout(attn_drop) | |
self.proj = nn.Linear(dim, dim, bias=proj_bias) | |
self.proj_drop = nn.Dropout(proj_drop) | |
self.rope = rope | |
def forward(self, x: Tensor, pos=None) -> Tensor: | |
B, N, C = x.shape | |
qkv = self.qkv(x).reshape(B, N, 3, self.num_heads, self.head_dim).permute(2, 0, 3, 1, 4) | |
q, k, v = qkv.unbind(0) | |
q, k = self.q_norm(q), self.k_norm(k) | |
if self.rope is not None: | |
q = self.rope(q, pos) | |
k = self.rope(k, pos) | |
if self.fused_attn: | |
x = F.scaled_dot_product_attention( | |
q, | |
k, | |
v, | |
dropout_p=self.attn_drop.p if self.training else 0.0, | |
) | |
else: | |
q = q * self.scale | |
attn = q @ k.transpose(-2, -1) | |
attn = attn.softmax(dim=-1) | |
attn = self.attn_drop(attn) | |
x = attn @ v | |
# attn_vis = ((q * self.scale) @ k.transpose(-2, -1)).softmax(dim=-1) | |
# import matplotlib.pyplot as plt | |
# for i in range (attn_vis.shape[0]): | |
# for j in range (attn_vis.shape[1]): | |
# for k in range(7): | |
# _ = attn_vis[i][j][k][7:].reshape(1,1,32,32) | |
# _ = F.interpolate(_, size=(256, 256), mode='nearest') | |
# _ = _.squeeze().cpu().detach().numpy() | |
# os.makedirs("/share/project/cwm/houyuan.chen/UPS_Lightning/plot/results/Net2_v15_epoch5_vis_for_goblet_attn_map/", exist_ok=True) | |
# plt.imsave(f"/share/project/cwm/houyuan.chen/UPS_Lightning/plot/results/Net2_v15_epoch5_vis_for_goblet_attn_map/attn_vis_img_{i}_head_{j}_token_{k}.png", _) | |
x = x.transpose(1, 2).reshape(B, N, C) | |
x = self.proj(x) | |
x = self.proj_drop(x) | |
return x | |
class MemEffAttention(Attention): | |
def forward(self, x: Tensor, attn_bias=None, pos=None) -> Tensor: | |
assert pos is None | |
if not XFORMERS_AVAILABLE: | |
if attn_bias is not None: | |
raise AssertionError("xFormers is required for using nested tensors") | |
return super().forward(x) | |
B, N, C = x.shape | |
qkv = self.qkv(x).reshape(B, N, 3, self.num_heads, C // self.num_heads) | |
q, k, v = unbind(qkv, 2) | |
x = memory_efficient_attention(q, k, v, attn_bias=attn_bias) | |
x = x.reshape([B, N, C]) | |
x = self.proj(x) | |
x = self.proj_drop(x) | |
return x | |