camenduru / stable-diffusion-webui

Stable Diffusion web UI
GNU Affero General Public License v3.0
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xformers #1

Closed camenduru closed 1 year ago

camenduru commented 1 year ago

https://github.com/camenduru/stable-diffusion-webui/blob/colab/modules/sd_hijack_optimizations.py

def reshape_heads_to_batch_dim(self, tensor):
    batch_size, seq_len, dim = tensor.shape
    head_size = self.heads
    tensor = tensor.reshape(batch_size, seq_len, head_size, dim // head_size)
    tensor = tensor.permute(0, 2, 1, 3).reshape(batch_size * head_size, seq_len, dim // head_size)
    return tensor

def reshape_batch_dim_to_heads(self, tensor):
    batch_size, seq_len, dim = tensor.shape
    head_size = self.heads
    tensor = tensor.reshape(batch_size // head_size, head_size, seq_len, dim)
    tensor = tensor.permute(0, 2, 1, 3).reshape(batch_size // head_size, seq_len, dim * head_size)
    return tensor

def xformers_attention_forward(self, x, context=None, mask=None):
    q_in = self.to_q(x)
    context = context if context is not None else x
    hypernetwork = shared.loaded_hypernetwork
    hypernetwork_layers = (hypernetwork.layers if hypernetwork is not None else {}).get(context.shape[2], None)
    if hypernetwork_layers is not None:
        k_in = self.to_k(hypernetwork_layers[0](context))
        v_in = self.to_v(hypernetwork_layers[1](context))
    else:
        k_in = self.to_k(context)
        v_in = self.to_v(context)

    q_in = reshape_heads_to_batch_dim(self, q_in)
    k_in = reshape_heads_to_batch_dim(self, k_in)
    v_in = reshape_heads_to_batch_dim(self, v_in)

    x = xformers.ops.memory_efficient_attention(q_in, k_in, v_in)
    x = reshape_batch_dim_to_heads(self, x)

    return self.to_out(x)
camenduru commented 1 year ago

https://github.com/camenduru/stable-diffusion-webui/blob/colab/modules/sd_hijack.py

# ldm.modules.diffusionmodules.model.AttnBlock.forward = sd_hijack_optimizations.xformers_attnblock_forward

ldm.modules.diffusionmodules.model.AttnBlock.forward = sd_hijack_optimizations.cross_attention_attnblock_forward

camenduru commented 1 year ago

from https://github.com/huggingface/diffusers/blob/main/src/diffusers/models/attention.py

camenduru commented 1 year ago
def xformers_attention_forward(self, x, context=None, mask=None):
    h = self.heads
    q_in = self.to_q(x)
    context = default(context, x)

    context_k, context_v = hypernetwork.apply_hypernetwork(shared.loaded_hypernetwork, context)
    k_in = self.to_k(context_k)
    v_in = self.to_v(context_v)

    q, k, v = map(lambda t: rearrange(t, 'b n (h d) -> b n h d', h=h), (q_in, k_in, v_in))
    del q_in, k_in, v_in
    out = xformers.ops.memory_efficient_attention(q, k, v, attn_bias=None)

    out = rearrange(out, 'b n h d -> b n (h d)', h=h)
    return self.to_out(out)
camenduru commented 1 year ago
# taken from https://github.com/huggingface/diffusers/blob/main/src/diffusers/models/attention.py and modified

def xformers_attention_forward(self, x, context=None, mask=None):
    h = self.heads
    q_in = self.to_q(x)
    context = default(context, x)

    context_k, context_v = hypernetwork.apply_hypernetwork(shared.loaded_hypernetwork, context)
    k_in = self.to_k(context_k)
    v_in = self.to_v(context_v)

    q, k, v = map(lambda t: t.reshape(t.shape[0], t.shape[1], self.heads, t.shape[2] // self.heads).permute(0, 2, 1, 3).reshape(t.shape[0] * self.heads, t.shape[1],  t.shape[2] // self.heads), (q_in, k_in, v_in))
    del q_in, k_in, v_in
    x = xformers.ops.memory_efficient_attention(q, k, v)

    x = x.reshape(x.shape[0] // self.heads, self.heads, x.shape[1], x.shape[2]).permute(0, 2, 1, 3).reshape(x.shape[0] // self.heads, x.shape[1],  x.shape[2] * self.heads)
    return self.to_out(x)
camenduru commented 1 year ago
def xformers_attnblock_forward(self, x):
    try:
        h_ = x
        h_ = self.norm(h_)
        q = self.q(h_)
        k = self.k(h_)
        v = self.v(h_)
        b, c, h, w = q.shape
        q, k, v = map(lambda t: rearrange(t, 'b c h w -> b (h w) c'), (q, k, v))
        q = q.contiguous()
        k = k.contiguous()
        v = v.contiguous()
        out = xformers.ops.memory_efficient_attention(q, k, v)
        out = rearrange(out, 'b (h w) c -> b c h w', h=h)
        out = self.proj_out(out)
        return x + out
    except NotImplementedError:
        return cross_attention_attnblock_forward(self, x)
camenduru commented 1 year ago
def xformers_attnblock_forward(self, x):
    try:
        h_ = x
        h_ = self.norm(h_)
        q = self.q(h_)
        k = self.k(h_)
        v = self.v(h_)
        b, c, h, w = q.shape
        q, k, v = map(lambda t: t.reshape(t.shape[0], t.shape[1], self.heads, t.shape[2] // self.heads).permute(0, 2, 1, 3).reshape(t.shape[0] * self.heads, t.shape[1], t.shape[2] // self.heads), (q, k, v))
        out = xformers.ops.memory_efficient_attention(q, k, v)
        out = out.reshape(x.shape[0] // self.heads, self.heads, out.shape[1], out.shape[2]).permute(0, 2, 1, 3).reshape(out.shape[0] // self.heads, out.shape[1], out.shape[2] * self.heads)
        out = self.proj_out(out)
        return x + out
    except NotImplementedError:
        return cross_attention_attnblock_forward(self, x)
camenduru commented 1 year ago

q, k, v = map(lambda t: rearrange(t, 'b n (h d) -> b n h d', h=h), (q_in, k_in, v_in))

q, k, v = map(lambda t: rearrange(t, 'b c h w -> b (h w) c'), (q, k, v))

camenduru commented 1 year ago

y = x.transpose(0, 2, 3, 1) y = rearrange(x, 'b c h w -> b h w c')

camenduru commented 1 year ago
q, k, v = map(lambda t: rearrange(t, 'b n (h d) -> b n h d', h=h), (q_in, k_in, v_in))
q, k, v = map(lambda t: t.reshape(t.shape[0], t.shape[1], self.heads, t.shape[2] // self.heads).permute(0, 2, 1, 3).reshape(t.shape[0] * self.heads, t.shape[1],  t.shape[2] // self.heads), (q_in, k_in, v_in))

q, k, v = map(lambda t: rearrange(t, 'b c h w -> b (h w) c'), (q1, k1, v))

how 😭?

camenduru commented 1 year ago

x = rearrange(x, "b c h w -> b (h w) c")

# first transpose: b c h w -> b h w c
x = x.transpose([0, 2, 3, 1])

# then compose two axes into one: b h w c-> b (h w) c
b, h, w, c = x.shape
x = x.reshape([b,  h * w, c])

x = x.permute(0, 2, 3, 1).reshape(b, h * w, c)

camenduru commented 1 year ago
b c h w -> b (h w) c
0 1 2 3

# first transpose: b c h w -> b h w c
x = x.transpose([0, 2, 3, 1])

# then compose two axes into one: b h w c-> b (h w) c
b, h, w, c = x.shape
x = x.reshape([b,  h * w, c])

b n (h d) -> b n h d
0 1 2 3
x = x.reshape()

batch_size, seq_len, dim = tensor.shape
head_size = self.heads
tensor = tensor.reshape(batch_size // head_size, head_size, seq_len, dim)
tensor = tensor.permute(0, 2, 1, 3).reshape(batch_size // head_size, seq_len, dim * head_size)

t.reshape(t.shape[0], t.shape[1], self.heads, t.shape[2] // self.heads).permute(0, 2, 1, 3).reshape(t.shape[0] * self.heads, t.shape[1],  t.shape[2] // self.heads)
camenduru commented 1 year ago
q, k, v = rearrange(qkv, "b (qkv heads c) h w -> qkv b heads c (h w)", heads=self.heads, qkv=3)
q, k, v = (
    qkv.reshape(b, 3, self.heads, self.dim_head, h, w)
    .permute(1, 0, 2, 3, 4, 5)
    .reshape(3, b, self.heads, self.dim_head, -1)
)
out = rearrange(out, "b heads c (h w) -> b (heads c) h w", heads=self.heads, h=h, w=w)
out = out.reshape(b, self.heads, self.dim_head, h, w).reshape(b, self.heads * self.dim_head, h, w)
x = einops.rearrange(x, "b h t -> b t h")
x = x.permute(0, 2, 1)
q, k, v = map(lambda t: rearrange(t, "b n (h d) -> (b h) n d", h=h), (q, k, v))
def reshape_heads_to_batch_dim(self, tensor):
        batch_size, seq_len, dim = tensor.shape
        head_size = self.heads
        tensor = tensor.reshape(batch_size, seq_len, head_size, dim // head_size)
        tensor = tensor.permute(0, 2, 1, 3).reshape(batch_size * head_size, seq_len, dim // head_size)
        return tensor
 x = rearrange(x, "b c h w -> b (h w) c")
 x = x.permute(0, 2, 3, 1).reshape(b, h * w, c)
x = rearrange(x, "b (h w) c -> b c h w", h=h, w=w)
x = x.reshape(b, h, w, c).permute(0, 3, 1, 2)
camenduru commented 1 year ago
def forward(self, x, context=None):
    # note: if no context is given, cross-attention defaults to self-attention
    b, c, h, w = x.shape
    x_in = x
    x = self.norm(x)
    x = self.proj_in(x)
    x = x.permute(0, 2, 3, 1).reshape(b, h * w, c)
    for block in self.transformer_blocks:
        x = block(x, context=context)
    x = x.reshape(b, h, w, c).permute(0, 3, 1, 2)
    x = self.proj_out(x)
    return x + x_in
camenduru commented 1 year ago

from code q, k, v = map(lambda t: rearrange(t, 'b n (h d) -> b n h d', h=h), (q_in, k_in, v_in))

q, k, v = map(lambda t: rearrange(t, "b n (h d) -> (b h) n d", h=h), (q_in, k_in, v_in))

batch_size, seq_len, dim = tensor.shape
head_size = self.heads
tensor = tensor.reshape(batch_size // head_size, head_size, seq_len, dim)
tensor = tensor.permute(0, 2, 1, 3).reshape(batch_size // head_size, seq_len, dim * head_size)

q, k, v = map(lambda t: t.reshape(t.shape[0], t.shape[1], self.heads, t.shape[2] // self.heads).permute(0, 2, 1, 3).reshape(t.shape[0] * self.heads, t.shape[1],  t.shape[2] // self.heads), (q_in, k_in, v_in))
q, k, v = map(lambda t: rearrange(t, 'b c h w -> b (h w) c'), (q1, k1, v))
 x = x.permute(0, 2, 3, 1).reshape(b, h * w, c)
camenduru commented 1 year ago
b n (h d) -> (b h) n d
0 1 (2 3) -> ((0 2) 1 3)

batch_size // head_size = 0
head_size = 1
seq_len = 2
dim = 3

permute(0, 2, 1, 3)

batch_size // head_size
seq_len
head_size * dim 
camenduru commented 1 year ago
x = rearrange(x, "b (h w) c -> b c h w", h=h, w=w)
x = x.reshape(b, h, w, c).permute(0, 3, 1, 2)
camenduru commented 1 year ago
class SpatialTransformer(nn.Module):
    """
    Transformer block for image-like data.
    First, project the input (aka embedding)
    and reshape to b, t, d.
    Then apply standard transformer action.
    Finally, reshape to image
    """

    def __init__(self, in_channels, n_heads, d_head, depth=1, dropout=0.0, context_dim=None):
        super().__init__()
        self.in_channels = in_channels
        inner_dim = n_heads * d_head
        self.norm = Normalize(in_channels)

        self.proj_in = nn.Conv2d(in_channels, inner_dim, kernel_size=1, stride=1, padding=0)

        self.transformer_blocks = nn.ModuleList(
            [
                BasicTransformerBlock(inner_dim, n_heads, d_head, dropout=dropout, context_dim=context_dim)
                for d in range(depth)
            ]
        )

        self.proj_out = zero_module(nn.Conv2d(inner_dim, in_channels, kernel_size=1, stride=1, padding=0))

    def forward(self, x, context=None):
        # note: if no context is given, cross-attention defaults to self-attention
        b, c, h, w = x.shape
        x_in = x
        x = self.norm(x)
        x = self.proj_in(x)
        x = x.permute(0, 2, 3, 1).reshape(b, h * w, c)
        for block in self.transformer_blocks:
            x = block(x, context=context)
        x = x.reshape(b, h, w, c).permute(0, 3, 1, 2)
        x = self.proj_out(x)
        return x + x_in
camenduru commented 1 year ago
class SpatialTransformer(nn.Module):
    """
    Transformer block for image-like data. First, project the input (aka embedding) and reshape to b, t, d. Then apply
    standard transformer action. Finally, reshape to image.
    Parameters:
        in_channels (:obj:`int`): The number of channels in the input and output.
        n_heads (:obj:`int`): The number of heads to use for multi-head attention.
        d_head (:obj:`int`): The number of channels in each head.
        depth (:obj:`int`, *optional*, defaults to 1): The number of layers of Transformer blocks to use.
        dropout (:obj:`float`, *optional*, defaults to 0.1): The dropout probability to use.
        context_dim (:obj:`int`, *optional*): The number of context dimensions to use.
    """

    def __init__(
        self,
        in_channels: int,
        n_heads: int,
        d_head: int,
        depth: int = 1,
        dropout: float = 0.0,
        num_groups: int = 32,
        context_dim: Optional[int] = None,
    ):
        super().__init__()
        self.n_heads = n_heads
        self.d_head = d_head
        self.in_channels = in_channels
        inner_dim = n_heads * d_head
        self.norm = torch.nn.GroupNorm(num_groups=num_groups, num_channels=in_channels, eps=1e-6, affine=True)

        self.proj_in = nn.Conv2d(in_channels, inner_dim, kernel_size=1, stride=1, padding=0)

        self.transformer_blocks = nn.ModuleList(
            [
                BasicTransformerBlock(inner_dim, n_heads, d_head, dropout=dropout, context_dim=context_dim)
                for d in range(depth)
            ]
        )

        self.proj_out = nn.Conv2d(inner_dim, in_channels, kernel_size=1, stride=1, padding=0)

    def _set_attention_slice(self, slice_size):
        for block in self.transformer_blocks:
            block._set_attention_slice(slice_size)

    def forward(self, hidden_states, context=None):
        # note: if no context is given, cross-attention defaults to self-attention
        batch, channel, height, weight = hidden_states.shape
        residual = hidden_states
        hidden_states = self.norm(hidden_states)
        hidden_states = self.proj_in(hidden_states)
        inner_dim = hidden_states.shape[1]
        hidden_states = hidden_states.permute(0, 2, 3, 1).reshape(batch, height * weight, inner_dim)
        for block in self.transformer_blocks:
            hidden_states = block(hidden_states, context=context)
        hidden_states = hidden_states.reshape(batch, height, weight, inner_dim).permute(0, 3, 1, 2)
        hidden_states = self.proj_out(hidden_states)
        return hidden_states + residual
camenduru commented 1 year ago
    def forward(self, x, context=None):
        # note: if no context is given, cross-attention defaults to self-attention
        b, c, h, w = x.shape
        x_in = x
        x = self.norm(x)
        x = self.proj_in(x)
        x = x.permute(0, 2, 3, 1).reshape(b, h * w, c)
        for block in self.transformer_blocks:
            x = block(x, context=context)
        x = x.reshape(b, h, w, c).permute(0, 3, 1, 2)
        x = self.proj_out(x)
        return x + x_in
    def forward(self, hidden_states, context=None):
        # note: if no context is given, cross-attention defaults to self-attention
        batch, channel, height, weight = hidden_states.shape
        residual = hidden_states
        hidden_states = self.norm(hidden_states)
        hidden_states = self.proj_in(hidden_states)
        inner_dim = hidden_states.shape[1]
        hidden_states = hidden_states.permute(0, 2, 3, 1).reshape(batch, height * weight, inner_dim)
        for block in self.transformer_blocks:
            hidden_states = block(hidden_states, context=context)
        hidden_states = hidden_states.reshape(batch, height, weight, inner_dim).permute(0, 3, 1, 2)
        hidden_states = self.proj_out(hidden_states)
        return hidden_states + residual
camenduru commented 1 year ago
class BasicTransformerBlock(nn.Module):
    def __init__(self, dim, n_heads, d_head, dropout=0.0, context_dim=None, gated_ff=True, checkpoint=True):
        super().__init__()
        self.attn1 = CrossAttention(
            query_dim=dim, heads=n_heads, dim_head=d_head, dropout=dropout
        )  # is a self-attention
        self.ff = FeedForward(dim, dropout=dropout, glu=gated_ff)
        self.attn2 = CrossAttention(
            query_dim=dim, context_dim=context_dim, heads=n_heads, dim_head=d_head, dropout=dropout
        )  # is self-attn if context is none
        self.norm1 = nn.LayerNorm(dim)
        self.norm2 = nn.LayerNorm(dim)
        self.norm3 = nn.LayerNorm(dim)
        self.checkpoint = checkpoint

    def forward(self, x, context=None):
        x = self.attn1(self.norm1(x)) + x
        x = self.attn2(self.norm2(x), context=context) + x
        x = self.ff(self.norm3(x)) + x
        return x
class BasicTransformerBlock(nn.Module):
    r"""
    A basic Transformer block.
    Parameters:
        dim (:obj:`int`): The number of channels in the input and output.
        n_heads (:obj:`int`): The number of heads to use for multi-head attention.
        d_head (:obj:`int`): The number of channels in each head.
        dropout (:obj:`float`, *optional*, defaults to 0.0): The dropout probability to use.
        context_dim (:obj:`int`, *optional*): The size of the context vector for cross attention.
        gated_ff (:obj:`bool`, *optional*, defaults to :obj:`False`): Whether to use a gated feed-forward network.
        checkpoint (:obj:`bool`, *optional*, defaults to :obj:`False`): Whether to use checkpointing.
    """

    def __init__(
        self,
        dim: int,
        n_heads: int,
        d_head: int,
        dropout=0.0,
        context_dim: Optional[int] = None,
        gated_ff: bool = True,
        checkpoint: bool = True,
    ):
        super().__init__()
        self.attn1 = CrossAttention(
            query_dim=dim, heads=n_heads, dim_head=d_head, dropout=dropout
        )  # is a self-attention
        self.ff = FeedForward(dim, dropout=dropout, glu=gated_ff)
        self.attn2 = CrossAttention(
            query_dim=dim, context_dim=context_dim, heads=n_heads, dim_head=d_head, dropout=dropout
        )  # is self-attn if context is none
        self.norm1 = nn.LayerNorm(dim)
        self.norm2 = nn.LayerNorm(dim)
        self.norm3 = nn.LayerNorm(dim)
        self.checkpoint = checkpoint

    def _set_attention_slice(self, slice_size):
        self.attn1._slice_size = slice_size
        self.attn2._slice_size = slice_size

    def forward(self, hidden_states, context=None):
        hidden_states = hidden_states.contiguous() if hidden_states.device.type == "mps" else hidden_states
        hidden_states = self.attn1(self.norm1(hidden_states)) + hidden_states
        hidden_states = self.attn2(self.norm2(hidden_states), context=context) + hidden_states
        hidden_states = self.ff(self.norm3(hidden_states)) + hidden_states
        return hidden_states
camenduru commented 1 year ago
class CrossAttention(nn.Module):
    def __init__(self, query_dim, context_dim=None, heads=8, dim_head=64, dropout=0.0):
        super().__init__()
        inner_dim = dim_head * heads
        context_dim = default(context_dim, query_dim)

        self.scale = dim_head**-0.5
        self.heads = heads

        self.to_q = nn.Linear(query_dim, inner_dim, bias=False)
        self.to_k = nn.Linear(context_dim, inner_dim, bias=False)
        self.to_v = nn.Linear(context_dim, inner_dim, bias=False)

        self.to_out = nn.Sequential(nn.Linear(inner_dim, query_dim), nn.Dropout(dropout))

    def reshape_heads_to_batch_dim(self, tensor):
        batch_size, seq_len, dim = tensor.shape
        head_size = self.heads
        tensor = tensor.reshape(batch_size, seq_len, head_size, dim // head_size)
        tensor = tensor.permute(0, 2, 1, 3).reshape(batch_size * head_size, seq_len, dim // head_size)
        return tensor

    def reshape_batch_dim_to_heads(self, tensor):
        batch_size, seq_len, dim = tensor.shape
        head_size = self.heads
        tensor = tensor.reshape(batch_size // head_size, head_size, seq_len, dim)
        tensor = tensor.permute(0, 2, 1, 3).reshape(batch_size // head_size, seq_len, dim * head_size)
        return tensor

    def forward(self, x, context=None, mask=None):
        batch_size, sequence_length, dim = x.shape

        h = self.heads

        q = self.to_q(x)
        context = default(context, x)
        k = self.to_k(context)
        v = self.to_v(context)

        #        q, k, v = map(lambda t: rearrange(t, "b n (h d) -> (b h) n d", h=h), (q, k, v))

        q = self.reshape_heads_to_batch_dim(q)
        k = self.reshape_heads_to_batch_dim(k)
        v = self.reshape_heads_to_batch_dim(v)

        sim = torch.einsum("b i d, b j d -> b i j", q, k) * self.scale

        if exists(mask):
            #            mask = rearrange(mask, "b ... -> b (...)")
            maks = mask.reshape(batch_size, -1)
            max_neg_value = -torch.finfo(sim.dtype).max
            #            mask = repeat(mask, "b j -> (b h) () j", h=h)
            mask = mask[:, None, :].repeat(h, 1, 1)
            #        x = rearrange(x, "b (h w) c -> b c h w", h=h, w=w)
            sim.masked_fill_(~mask, max_neg_value)

        # attention, what we cannot get enough of
        attn = sim.softmax(dim=-1)

        out = torch.einsum("b i j, b j d -> b i d", attn, v)
        out = self.reshape_batch_dim_to_heads(out)
        #        out = rearrange(out, "(b h) n d -> b n (h d)", h=h)
        return self.to_out(out)
camenduru commented 1 year ago
class CrossAttention(nn.Module):
    r"""
    A cross attention layer.
    Parameters:
        query_dim (:obj:`int`): The number of channels in the query.
        context_dim (:obj:`int`, *optional*):
            The number of channels in the context. If not given, defaults to `query_dim`.
        heads (:obj:`int`,  *optional*, defaults to 8): The number of heads to use for multi-head attention.
        dim_head (:obj:`int`,  *optional*, defaults to 64): The number of channels in each head.
        dropout (:obj:`float`, *optional*, defaults to 0.0): The dropout probability to use.
    """

    def __init__(
        self, query_dim: int, context_dim: Optional[int] = None, heads: int = 8, dim_head: int = 64, dropout: int = 0.0
    ):
        super().__init__()
        inner_dim = dim_head * heads
        context_dim = context_dim if context_dim is not None else query_dim

        self.scale = dim_head**-0.5
        self.heads = heads
        # for slice_size > 0 the attention score computation
        # is split across the batch axis to save memory
        # You can set slice_size with `set_attention_slice`
        self._slice_size = None

        self.to_q = nn.Linear(query_dim, inner_dim, bias=False)
        self.to_k = nn.Linear(context_dim, inner_dim, bias=False)
        self.to_v = nn.Linear(context_dim, inner_dim, bias=False)

        self.to_out = nn.Sequential(nn.Linear(inner_dim, query_dim), nn.Dropout(dropout))

    def reshape_heads_to_batch_dim(self, tensor):
        batch_size, seq_len, dim = tensor.shape
        head_size = self.heads
        tensor = tensor.reshape(batch_size, seq_len, head_size, dim // head_size)
        tensor = tensor.permute(0, 2, 1, 3).reshape(batch_size * head_size, seq_len, dim // head_size)
        return tensor

    def reshape_batch_dim_to_heads(self, tensor):
        batch_size, seq_len, dim = tensor.shape
        head_size = self.heads
        tensor = tensor.reshape(batch_size // head_size, head_size, seq_len, dim)
        tensor = tensor.permute(0, 2, 1, 3).reshape(batch_size // head_size, seq_len, dim * head_size)
        return tensor

    def forward(self, hidden_states, context=None, mask=None):
        batch_size, sequence_length, _ = hidden_states.shape

        query = self.to_q(hidden_states)
        context = context if context is not None else hidden_states
        key = self.to_k(context)
        value = self.to_v(context)

        dim = query.shape[-1]

        query = self.reshape_heads_to_batch_dim(query)
        key = self.reshape_heads_to_batch_dim(key)
        value = self.reshape_heads_to_batch_dim(value)

        # TODO(PVP) - mask is currently never used. Remember to re-implement when used

        # attention, what we cannot get enough of

        if self._slice_size is None or query.shape[0] // self._slice_size == 1:
            hidden_states = self._attention(query, key, value)
        else:
            hidden_states = self._sliced_attention(query, key, value, sequence_length, dim)

        return self.to_out(hidden_states)

    def _attention(self, query, key, value):
        # TODO: use baddbmm for better performance
        attention_scores = torch.matmul(query, key.transpose(-1, -2)) * self.scale
        attention_probs = attention_scores.softmax(dim=-1)
        # compute attention output
        hidden_states = torch.matmul(attention_probs, value)
        # reshape hidden_states
        hidden_states = self.reshape_batch_dim_to_heads(hidden_states)
        return hidden_states

    def _sliced_attention(self, query, key, value, sequence_length, dim):
        batch_size_attention = query.shape[0]
        hidden_states = torch.zeros(
            (batch_size_attention, sequence_length, dim // self.heads), device=query.device, dtype=query.dtype
        )
        slice_size = self._slice_size if self._slice_size is not None else hidden_states.shape[0]
        for i in range(hidden_states.shape[0] // slice_size):
            start_idx = i * slice_size
            end_idx = (i + 1) * slice_size
            attn_slice = (
                torch.matmul(query[start_idx:end_idx], key[start_idx:end_idx].transpose(1, 2)) * self.scale
            )  # TODO: use baddbmm for better performance
            attn_slice = attn_slice.softmax(dim=-1)
            attn_slice = torch.matmul(attn_slice, value[start_idx:end_idx])

            hidden_states[start_idx:end_idx] = attn_slice

        # reshape hidden_states
        hidden_states = self.reshape_batch_dim_to_heads(hidden_states)
        return hidden_states
camenduru commented 1 year ago

attention.py CrossAttention BasicTransformerBlock

unet_blocks.py SpatialTransformer class CrossAttnUpBlock2D(nn.Module): class UNetMidBlock2DCrossAttn(nn.Module): class CrossAttnDownBlock2D(nn.Module):

unet_2d_condition.py UNet2DConditionModel

camenduru commented 1 year ago
class MemoryEfficientCrossAttention(nn.Module):
    def __init__(self, query_dim, context_dim=None, heads=8, dim_head=64, dropout=0.0):
        super().__init__()
        inner_dim = dim_head * heads
        context_dim = default(context_dim, query_dim)

        self.heads = heads
        self.dim_head = dim_head

        self.to_q = nn.Linear(query_dim, inner_dim, bias=False)
        self.to_k = nn.Linear(context_dim, inner_dim, bias=False)
        self.to_v = nn.Linear(context_dim, inner_dim, bias=False)

        self.to_out = nn.Sequential(nn.Linear(inner_dim, query_dim), nn.Dropout(dropout))
        self.attention_op: Optional[Any] = None

    def forward(self, x, context=None, mask=None):
        q = self.to_q(x)
        context = default(context, x)
        k = self.to_k(context)
        v = self.to_v(context)

        b, _, _ = q.shape
        q, k, v = map(
            lambda t: t.unsqueeze(3)
            .reshape(b, t.shape[1], self.heads, self.dim_head)
            .permute(0, 2, 1, 3)
            .reshape(b * self.heads, t.shape[1], self.dim_head)
            .contiguous(),
            (q, k, v),
        )

        # actually compute the attention, what we cannot get enough of
        out = xformers.ops.memory_efficient_attention(q, k, v, attn_bias=None, op=self.attention_op)

        # TODO: Use this directly in the attention operation, as a bias
        if exists(mask):
            raise NotImplementedError
        out = (
            out.unsqueeze(0)
            .reshape(b, self.heads, out.shape[1], self.dim_head)
            .permute(0, 2, 1, 3)
            .reshape(b, out.shape[1], self.heads * self.dim_head)
        )
        return self.to_out(out)
camenduru commented 1 year ago
    def _attention(self, query, key, value):
        # TODO: use baddbmm for better performance
        attention_scores = torch.matmul(query, key.transpose(-1, -2)) * self.scale
        attention_probs = attention_scores.softmax(dim=-1)
        # compute attention output
        hidden_states = torch.matmul(attention_probs, value)
        # reshape hidden_states
        hidden_states = self.reshape_batch_dim_to_heads(hidden_states)
        return hidden_states
    def _sliced_attention(self, query, key, value, sequence_length, dim):
        batch_size_attention = query.shape[0]
        hidden_states = torch.zeros(
            (batch_size_attention, sequence_length, dim // self.heads), device=query.device, dtype=query.dtype
        )
        slice_size = self._slice_size if self._slice_size is not None else hidden_states.shape[0]
        for i in range(hidden_states.shape[0] // slice_size):
            start_idx = i * slice_size
            end_idx = (i + 1) * slice_size
            attn_slice = (
                torch.matmul(query[start_idx:end_idx], key[start_idx:end_idx].transpose(1, 2)) * self.scale
            )  # TODO: use baddbmm for better performance
            attn_slice = attn_slice.softmax(dim=-1)
            attn_slice = torch.matmul(attn_slice, value[start_idx:end_idx])

            hidden_states[start_idx:end_idx] = attn_slice
camenduru commented 1 year ago
def xformers_attention_forward(self, x, context=None, mask=None):
    h = self.heads
    q_in = self.to_q(x)
    context = default(context, x)

    context_k, context_v = hypernetwork.apply_hypernetwork(shared.loaded_hypernetwork, context)
    k_in = self.to_k(context_k)
    v_in = self.to_v(context_v)

    print(f"before (b n (h d) -> (b h) n d) q_in: {q_in.shape} | {q_in.dtype}")
    print(f"before (b n (h d) -> (b h) n d) k_in: {k_in.shape} | {k_in.dtype}")
    print(f"before (b n (h d) -> (b h) n d) v_in: {v_in.shape} | {v_in.dtype}")

    q, k, v = map(lambda t: rearrange(t, 'b n (h d) -> (b h) n d', h=h), (q_in, k_in, v_in))

    print(f"after (b n (h d) -> (b h) n d) q: {q.shape} | {q.dtype}")
    print(f"after (b n (h d) -> (b h) n d) k: {k.shape} | {k.dtype}")
    print(f"after (b n (h d) -> (b h) n d) v: {v.shape} | {v.dtype}")

    del q_in, k_in, v_in
    out = xformers.ops.memory_efficient_attention(q, k, v, attn_bias=None)

    print(f"before ((b h) n d -> b n (h d)) out: {out.shape} | {out.dtype}")

    out = rearrange(out, '(b h) n d -> b n (h d)', h=h)

    print(f"after ((b h) n d -> b n (h d)) out: {out.shape} | {out.dtype}")

    return self.to_out(out)
camenduru commented 1 year ago

duck Steps: 50, Sampler: Euler a, CFG scale: 7, Seed: 1886223165, Size: 512x512, Model hash: 7460a6fa


before (b n h d -> b n (h d)) out: torch.Size([2, 4096, 8, 40]) | torch.float16 after (b n h d -> b n (h d)) out: torch.Size([2, 4096, 320]) | torch.float16 100% | 50/50 [00:29<00:00, 1.72it/s] Total progress: 100% | 50/50 [00:28<00:00, 1.73it/s]


before ((b h) n d -> b n (h d)) out: torch.Size([16, 4096, 40]) | torch.float16 after ((b h) n d -> b n (h d)) out: torch.Size([2, 4096, 320]) | torch.float16 100% | 50/50 [00:30<00:00, 1.66it/s] Total progress: 100% | 50/50 [00:29<00:00, 1.72it/s]

camenduru commented 1 year ago

xformers.ops.memory_efficient_attention Don't like this one before rearrange(b n (h d) -> b n h d) torch.Size([2, 4096, 320]) | torch.float16 after rearrange(b n (h d) -> b n h d) torch.Size([2, 4096, 8, 40]) | torch.float16

xformers.ops.memory_efficient_attention like this one before rearrange(b n (h d) -> (b h) n d) torch.Size([2, 4096, 320]) | torch.float16 after rearrange(b n (h d) -> (b h) n d) torch.Size([16, 4096, 40]) | torch.float16

camenduru commented 1 year ago
def xformers_attention_forward(self, x, context=None, mask=None):
    h = self.heads
    q_in = self.to_q(x)
    context = default(context, x)
    context_k, context_v = hypernetwork.apply_hypernetwork(shared.loaded_hypernetwork, context)
    k_in = self.to_k(context_k)
    v_in = self.to_v(context_v)
    q, k, v = map(lambda t: rearrange(t, 'b n (h d) -> (b h) n d', h=h), (q_in, k_in, v_in))
    del q_in, k_in, v_in
    if shared.cmd_opts.no_half:
      out = xformers.ops.memory_efficient_attention(q, k, v, attn_bias=None).float()
    else:
      out = xformers.ops.memory_efficient_attention(q, k, v, attn_bias=None).half()
    print(f"xformers_attention_forward before ((b h) n d -> b n (h d)) out: {out.shape} | {out.dtype}")
    out = rearrange(out, '(b h) n d -> b n (h d)', h=h)
    print(f"xformers_attention_forward after ((b h) n d -> b n (h d)) out: {out.shape} | {out.dtype}")
    return self.to_out(out)
def xformers_attnblock_forward(self, x):
    try:
        h_ = x
        h_ = self.norm(h_)
        q = self.q(h_)
        k = self.k(h_)
        v = self.v(h_)
        b, c, h, w = q.shape
        q, k, v = map(lambda t: rearrange(t, 'b c h w -> b (h w) c'), (q, k, v))
        q = q.contiguous()
        k = k.contiguous()
        v = v.contiguous()
        if shared.cmd_opts.no_half:
          out = xformers.ops.memory_efficient_attention(q, k, v).float()
        else:
          out = xformers.ops.memory_efficient_attention(q, k, v).half()
        out = rearrange(out, 'b (h w) c -> b c h w', h=h)
        out = self.proj_out(out)
        return x + out
    except NotImplementedError:
        return cross_attention_attnblock_forward(self, x)
camenduru commented 1 year ago

!pip install -qq https://github.com/metrolobo/xformers_wheels/releases/download/1d31a3ac_various_6/xformers-0.0.14.dev0-cp37-cp37m-linux_x86_64.whl !pip install -qq -U --pre triton

camenduru commented 1 year ago

fixes RuntimeError: Expected query.dim() == 3 to be true, but got false. (Could this error message be improved? If so, please report an enhancement request to PyTorch.) and RuntimeError: Input type (torch.cuda.FloatTensor) and weight type (torch.cuda.HalfTensor) should be the same