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- # 🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨
- # This file was automatically generated from src/transformers/models/bamba/modular_bamba.py.
- # Do NOT edit this file manually as any edits will be overwritten by the generation of
- # the file from the modular. If any change should be done, please apply the change to the
- # modular_bamba.py file directly. One of our CI enforces this.
- # 🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨
- # Copyright 2024 IBM and the HuggingFace Inc. team. All rights reserved.
- #
- # This code is based on EleutherAI's GPT-NeoX library and the GPT-NeoX
- # and OPT implementations in this library. It has been modified from its
- # original forms to accommodate minor architectural differences compared
- # to GPT-NeoX and OPT used by the Meta AI team that trained the model.
- #
- # Licensed under the Apache License, Version 2.0 (the "License");
- # you may not use this file except in compliance with the License.
- # You may obtain a copy of the License at
- #
- # http://www.apache.org/licenses/LICENSE-2.0
- #
- # Unless required by applicable law or agreed to in writing, software
- # distributed under the License is distributed on an "AS IS" BASIS,
- # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- # See the License for the specific language governing permissions and
- # limitations under the License.
- from collections.abc import Callable
- from typing import Optional, TypedDict
- import torch
- from torch import nn
- from ... import initialization as init
- from ...activations import ACT2FN
- from ...cache_utils import Cache, DynamicCache
- from ...generation import GenerationMixin
- from ...integrations import use_kernel_forward_from_hub, use_kernelized_func
- from ...integrations.hub_kernels import lazy_load_kernel
- from ...masking_utils import create_causal_mask
- from ...modeling_layers import GradientCheckpointingLayer
- from ...modeling_outputs import BaseModelOutputWithPast, CausalLMOutputWithPast
- from ...modeling_rope_utils import ROPE_INIT_FUNCTIONS, dynamic_rope_update
- from ...modeling_utils import ALL_ATTENTION_FUNCTIONS, PreTrainedModel
- from ...processing_utils import Unpack
- from ...utils import TransformersKwargs, auto_docstring, can_return_tuple, is_torchdynamo_compiling, logging
- from ...utils.generic import maybe_autocast, merge_with_config_defaults
- from ...utils.import_utils import resolve_internal_import
- from ...utils.output_capturing import capture_outputs
- from .configuration_bamba import BambaConfig
- logger = logging.get_logger(__name__)
- class BambaFlashAttentionKwargs(TypedDict, total=False):
- """
- Keyword arguments for advanced Flash Attention, causal-conv1d, and mamba_ssm kernel usage.
- Use cases include padding-free training and fewer `torch.compile` graph breaks.
- cu_seq_lens_q (`torch.LongTensor`):
- Gets cumulative sequence length for query state.
- cu_seq_lens_k (`torch.LongTensor`):
- Gets cumulative sequence length for key state.
- max_length_q (`int`):
- Maximum sequence length for query state.
- max_length_k (`int`):
- Maximum sequence length for key state.
- seq_idx (`torch.IntTensor`):
- Index of each packed sequence.
- """
- cu_seq_lens_q: torch.LongTensor
- cu_seq_lens_k: torch.LongTensor
- max_length_q: int
- max_length_k: int
- seq_idx: torch.IntTensor
- class BambaRotaryEmbedding(nn.Module):
- inv_freq: torch.Tensor # fix linting for `register_buffer`
- def __init__(self, config: BambaConfig, device=None):
- super().__init__()
- self.max_seq_len_cached = config.max_position_embeddings
- self.original_max_seq_len = config.max_position_embeddings
- self.config = config
- self.rope_type = self.config.rope_parameters["rope_type"]
- rope_init_fn: Callable = self.compute_default_rope_parameters
- if self.rope_type != "default":
- rope_init_fn = ROPE_INIT_FUNCTIONS[self.rope_type]
- inv_freq, self.attention_scaling = rope_init_fn(self.config, device)
- self.register_buffer("inv_freq", inv_freq, persistent=False)
- self.register_buffer("original_inv_freq", inv_freq.clone(), persistent=False)
- @staticmethod
- def compute_default_rope_parameters(
- config: BambaConfig | None = None,
- device: Optional["torch.device"] = None,
- seq_len: int | None = None,
- ) -> tuple["torch.Tensor", float]:
- """
- Computes the inverse frequencies according to the original RoPE implementation
- Args:
- config ([`~transformers.PreTrainedConfig`]):
- The model configuration.
- device (`torch.device`):
- The device to use for initialization of the inverse frequencies.
- seq_len (`int`, *optional*):
- The current sequence length. Unused for this type of RoPE.
- Returns:
- Tuple of (`torch.Tensor`, `float`), containing the inverse frequencies for the RoPE embeddings and the
- post-processing scaling factor applied to the computed cos/sin (unused in this type of RoPE).
- """
- base = config.rope_parameters["rope_theta"]
- dim = getattr(config, "head_dim", None) or config.hidden_size // config.num_attention_heads
- attention_factor = 1.0 # Unused in this type of RoPE
- # Compute the inverse frequencies
- inv_freq = 1.0 / (
- base ** (torch.arange(0, dim, 2, dtype=torch.int64).to(device=device, dtype=torch.float) / dim)
- )
- return inv_freq, attention_factor
- @torch.no_grad()
- @dynamic_rope_update # power user: used with advanced RoPE types (e.g. dynamic rope)
- def forward(self, x, position_ids):
- inv_freq_expanded = self.inv_freq[None, :, None].float().expand(position_ids.shape[0], -1, 1).to(x.device)
- position_ids_expanded = position_ids[:, None, :].float()
- device_type = x.device.type if isinstance(x.device.type, str) and x.device.type != "mps" else "cpu"
- with maybe_autocast(device_type=device_type, enabled=False): # Force float32
- freqs = (inv_freq_expanded.float() @ position_ids_expanded.float()).transpose(1, 2)
- emb = torch.cat((freqs, freqs), dim=-1)
- cos = emb.cos() * self.attention_scaling
- sin = emb.sin() * self.attention_scaling
- return cos.to(dtype=x.dtype), sin.to(dtype=x.dtype)
- def rotate_half(x):
- """Rotates half the hidden dims of the input."""
- x1 = x[..., : x.shape[-1] // 2]
- x2 = x[..., x.shape[-1] // 2 :]
- return torch.cat((-x2, x1), dim=-1)
- def repeat_kv(hidden_states: torch.Tensor, n_rep: int) -> torch.Tensor:
- """
- This is the equivalent of torch.repeat_interleave(x, dim=1, repeats=n_rep). The hidden states go from (batch,
- num_key_value_heads, seqlen, head_dim) to (batch, num_attention_heads, seqlen, head_dim)
- """
- batch, num_key_value_heads, slen, head_dim = hidden_states.shape
- if n_rep == 1:
- return hidden_states
- hidden_states = hidden_states[:, :, None, :, :].expand(batch, num_key_value_heads, n_rep, slen, head_dim)
- return hidden_states.reshape(batch, num_key_value_heads * n_rep, slen, head_dim)
- def eager_attention_forward(
- module: nn.Module,
- query: torch.Tensor,
- key: torch.Tensor,
- value: torch.Tensor,
- attention_mask: torch.Tensor | None,
- scaling: float,
- dropout: float = 0.0,
- **kwargs: Unpack[TransformersKwargs],
- ):
- key_states = repeat_kv(key, module.num_key_value_groups)
- value_states = repeat_kv(value, module.num_key_value_groups)
- attn_weights = torch.matmul(query, key_states.transpose(2, 3)) * scaling
- if attention_mask is not None:
- attn_weights = attn_weights + attention_mask
- attn_weights = nn.functional.softmax(attn_weights, dim=-1, dtype=torch.float32).to(query.dtype)
- attn_weights = nn.functional.dropout(attn_weights, p=dropout, training=module.training)
- attn_output = torch.matmul(attn_weights, value_states)
- attn_output = attn_output.transpose(1, 2).contiguous()
- return attn_output, attn_weights
- # Adapted from transformers.models.glm.modular_glm.apply_rotary_pos_emb
- def apply_rotary_pos_emb(q, k, cos, sin, unsqueeze_dim=1):
- """Applies Rotary Position Embedding to the query and key tensors.
- Removes the interleaving of cos and sin from GLM
- Args:
- q (`torch.Tensor`): The query tensor.
- k (`torch.Tensor`): The key tensor.
- cos (`torch.Tensor`): The cosine part of the rotary embedding.
- sin (`torch.Tensor`): The sine part of the rotary embedding.
- unsqueeze_dim (`int`, *optional*, defaults to 1):
- The 'unsqueeze_dim' argument specifies the dimension along which to unsqueeze cos[position_ids] and
- sin[position_ids] so that they can be properly broadcasted to the dimensions of q and k. For example, note
- that cos[position_ids] and sin[position_ids] have the shape [batch_size, seq_len, head_dim]. Then, if q and
- k have the shape [batch_size, heads, seq_len, head_dim], then setting unsqueeze_dim=1 makes
- cos[position_ids] and sin[position_ids] broadcastable to the shapes of q and k. Similarly, if q and k have
- the shape [batch_size, seq_len, heads, head_dim], then set unsqueeze_dim=2.
- Returns:
- `tuple(torch.Tensor)` comprising of the query and key tensors rotated using the Rotary Position Embedding.
- """
- cos = cos.unsqueeze(unsqueeze_dim)
- sin = sin.unsqueeze(unsqueeze_dim)
- # Keep half or full tensor for later concatenation
- rotary_dim = cos.shape[-1]
- q_rot, q_pass = q[..., :rotary_dim], q[..., rotary_dim:]
- k_rot, k_pass = k[..., :rotary_dim], k[..., rotary_dim:]
- # Apply rotary embeddings on the first half or full tensor
- q_embed = (q_rot * cos) + (rotate_half(q_rot) * sin)
- k_embed = (k_rot * cos) + (rotate_half(k_rot) * sin)
- # Concatenate back to full shape
- q_embed = torch.cat([q_embed, q_pass], dim=-1)
- k_embed = torch.cat([k_embed, k_pass], dim=-1)
- return q_embed, k_embed
- @use_kernelized_func(apply_rotary_pos_emb)
- class BambaAttention(nn.Module):
- """Multi-headed attention from 'Attention Is All You Need' paper"""
- def __init__(self, config: BambaConfig, layer_idx: int):
- super().__init__()
- self.config = config
- self.layer_idx = layer_idx
- self.head_dim = getattr(config, "head_dim", config.hidden_size // config.num_attention_heads)
- self.num_key_value_groups = config.num_attention_heads // config.num_key_value_heads
- self.scaling = self.head_dim**-0.5
- self.attention_dropout = config.attention_dropout
- self.is_causal = True
- self.q_proj = nn.Linear(
- config.hidden_size, config.num_attention_heads * self.head_dim, bias=config.attention_bias
- )
- self.k_proj = nn.Linear(
- config.hidden_size, config.num_key_value_heads * self.head_dim, bias=config.attention_bias
- )
- self.v_proj = nn.Linear(
- config.hidden_size, config.num_key_value_heads * self.head_dim, bias=config.attention_bias
- )
- self.o_proj = nn.Linear(
- config.num_attention_heads * self.head_dim, config.hidden_size, bias=config.attention_bias
- )
- def forward(
- self,
- hidden_states: torch.Tensor,
- position_embeddings: tuple[torch.Tensor, torch.Tensor] | None = None,
- attention_mask: torch.Tensor | None = None,
- past_key_values: Cache | None = None,
- **kwargs: Unpack[TransformersKwargs],
- ) -> tuple[torch.Tensor, torch.Tensor]:
- input_shape = hidden_states.shape[:-1]
- hidden_shape = (*input_shape, -1, self.head_dim)
- query_states = self.q_proj(hidden_states).view(hidden_shape).transpose(1, 2)
- key_states = self.k_proj(hidden_states).view(hidden_shape).transpose(1, 2)
- value_states = self.v_proj(hidden_states).view(hidden_shape).transpose(1, 2)
- cos, sin = position_embeddings
- query_states, key_states = apply_rotary_pos_emb(query_states, key_states, cos, sin)
- if past_key_values is not None:
- key_states, value_states = past_key_values.update(key_states, value_states, self.layer_idx)
- attention_interface: Callable = ALL_ATTENTION_FUNCTIONS.get_interface(
- self.config._attn_implementation, eager_attention_forward
- )
- attn_output, attn_weights = attention_interface(
- self,
- query_states,
- key_states,
- value_states,
- attention_mask,
- dropout=0.0 if not self.training else self.attention_dropout,
- scaling=self.scaling,
- **kwargs,
- )
- attn_output = attn_output.reshape(*input_shape, -1).contiguous()
- attn_output = self.o_proj(attn_output)
- return attn_output, attn_weights
- class BambaRMSNormGated(torch.nn.Module):
- def __init__(self, hidden_size, eps=1e-6):
- super().__init__()
- self.weight = nn.Parameter(torch.ones(hidden_size))
- self.variance_epsilon = eps
- def forward(self, hidden_states, gate=None):
- input_dtype = hidden_states.dtype
- hidden_states = hidden_states.to(torch.float32)
- if gate is not None:
- hidden_states = hidden_states * nn.functional.silu(gate.to(torch.float32))
- variance = hidden_states.pow(2).mean(-1, keepdim=True)
- hidden_states = hidden_states * torch.rsqrt(variance + self.variance_epsilon)
- return self.weight * hidden_states.to(input_dtype)
- # Helper methods for segment sum computation
- def pad_tensor_by_size(input_tensor: torch.Tensor, pad_size: int):
- """
- Padding x tensor with `pad_size` on the seq_len dim (dim=1)
- Assumes that we only have tensors of either size 4 or 3
- """
- pad_shape = (0, 0, 0, 0, 0, pad_size, 0, 0) if len(input_tensor.shape) == 4 else (0, 0, 0, pad_size, 0, 0)
- return torch.nn.functional.pad(input_tensor, pad_shape, mode="constant", value=0)
- def reshape_into_chunks(input_tensor, pad_size, chunk_size):
- """
- Padding input_tensor with `pad_size` on the seq_len dim (dim=1) and
- simultaneously splitting it into chunk sequences.
- Assumes that we only have tensors of either size 4 or 3
- """
- # [bsz, seq_len, ...] -> [bsz, seq_len multiple of chunk_size, ...]
- input_tensor = pad_tensor_by_size(input_tensor, pad_size)
- if len(input_tensor.shape) == 3:
- # [bsz, seq_len multiple of chunk_size, num_heads] -> [bsz, -1, chunk_size, num_heads]
- return input_tensor.reshape(input_tensor.shape[0], -1, chunk_size, input_tensor.shape[2])
- else:
- # [bsz, seq_len multiple of chunk_size, num_heads, head_dim or state_size] -> [bsz, -1, chunk_size, num_heads, head_dim or state_size]
- return input_tensor.reshape(
- input_tensor.shape[0], -1, chunk_size, input_tensor.shape[2], input_tensor.shape[3]
- )
- def segment_sum(input_tensor):
- """
- More stable segment sum calculation. Uses cumulative sums and masking instead of direct subtractions.
- """
- chunk_size = input_tensor.size(-1)
- # 1. expand input tensor to have an additional dimension and repeat along that dimension
- # [..., chunk_size] -> [..., chunk_size, chunk_size]
- input_tensor = input_tensor[..., None].expand(*input_tensor.size(), chunk_size)
- # 2. create a lower triangular mask with the diagonal set to 0 to 0 out elements above diag
- mask = torch.tril(torch.ones(chunk_size, chunk_size, device=input_tensor.device, dtype=torch.bool), diagonal=-1)
- input_tensor = input_tensor.masked_fill(~mask, 0)
- # 3. compute actual cumsum
- tensor_segsum = torch.cumsum(input_tensor, dim=-2)
- # 4. apply mask to keep only the lower triangular part of the cumulative sum result (incl diagonal this time)
- mask = torch.tril(torch.ones(chunk_size, chunk_size, device=input_tensor.device, dtype=torch.bool), diagonal=0)
- tensor_segsum = tensor_segsum.masked_fill(~mask, -torch.inf)
- return tensor_segsum
- def apply_mask_to_padding_states(hidden_states, attention_mask):
- """
- Tunes out the hidden states for padding tokens, see https://github.com/state-spaces/mamba/issues/66
- """
- # NOTE: attention mask is a 2D boolean tensor
- if attention_mask is not None and attention_mask.shape[1] > 1 and attention_mask.shape[0] > 1:
- dtype = hidden_states.dtype
- hidden_states = (hidden_states * attention_mask[:, :, None]).to(dtype)
- return hidden_states
- # Adapted from transformers.models.mamba2.modeling_mamba2.Mamba2Mixer
- class BambaMixer(nn.Module):
- """
- Compute ∆, A, B, C, and D the state space parameters and compute the `contextualized_states`.
- A, D are input independent (see Mamba paper [1] Section 3.5.2 "Interpretation of A" for why A isn't selective)
- ∆, B, C are input-dependent (this is a key difference between Mamba and the linear time invariant S4,
- and is why Mamba is called **selective** state spaces)
- The are a few differences between this and Mamba2Mixer:
- - The variable use_precomputed_states is slightly different due to the hybrid cache structure
- - There's a few non-obvious bugs fixed with batching in the slow path that exist in main
- - Some extra variables that our layer doesn't need have been removed
- - We ported most of the refactors in https://github.com/huggingface/transformers/pull/35154, which is (as of Dec 18, 2024) unmerged
- """
- def __init__(self, config: BambaConfig, layer_idx: int):
- super().__init__()
- self.num_heads = config.mamba_n_heads
- self.hidden_size = config.hidden_size
- self.ssm_state_size = config.mamba_d_state
- self.conv_kernel_size = config.mamba_d_conv
- self.intermediate_size = int(config.mamba_expand * self.hidden_size)
- self.layer_idx = layer_idx
- self.use_conv_bias = config.mamba_conv_bias
- self.activation = config.hidden_act
- self.act = ACT2FN[config.hidden_act]
- self.use_bias = config.mamba_proj_bias
- self.layer_norm_epsilon = config.rms_norm_eps
- self.n_groups = config.mamba_n_groups
- self.head_dim = config.mamba_d_head
- self.chunk_size = config.mamba_chunk_size
- self.time_step_limit = config.time_step_limit
- self.time_step_min = config.time_step_min
- self.time_step_max = config.time_step_max
- self.conv_dim = self.intermediate_size + 2 * self.n_groups * self.ssm_state_size
- self.conv1d = nn.Conv1d(
- in_channels=self.conv_dim,
- out_channels=self.conv_dim,
- bias=config.mamba_conv_bias,
- kernel_size=self.conv_kernel_size,
- groups=self.conv_dim,
- padding=self.conv_kernel_size - 1,
- )
- # projection of the input hidden states
- projection_size = self.intermediate_size + self.conv_dim + self.num_heads
- self.in_proj = nn.Linear(
- self.hidden_size,
- projection_size,
- bias=self.use_bias,
- )
- # selective projection used to make dt, B and C input dependent
- # time step projection (discretization)
- # instantiate once and copy inv_dt in init_weights of PretrainedModel
- self.dt_bias = nn.Parameter(torch.ones(self.num_heads))
- # S4D real initialization. These are not discretized!
- # The core is to load them, compute the discrete states, then write the updated state. Keeps the memory bounded
- A = torch.arange(1, self.num_heads + 1)
- self.A_log = nn.Parameter(torch.log(A))
- self.norm = BambaRMSNormGated(self.intermediate_size, eps=self.layer_norm_epsilon)
- self.D = nn.Parameter(torch.ones(self.num_heads))
- self.out_proj = nn.Linear(self.intermediate_size, self.hidden_size, bias=self.use_bias)
- global causal_conv1d_update, causal_conv1d_fn
- causal_conv1d = lazy_load_kernel("causal-conv1d")
- causal_conv1d_update = getattr(causal_conv1d, "causal_conv1d_update", None)
- causal_conv1d_fn = getattr(causal_conv1d, "causal_conv1d_fn", None)
- global selective_state_update, mamba_chunk_scan_combined, mamba_split_conv1d_scan_combined
- mamba_ssm = lazy_load_kernel("mamba-ssm")
- selective_state_update = resolve_internal_import(
- mamba_ssm, chained_path="ops.triton.selective_state_update.selective_state_update"
- )
- mamba_chunk_scan_combined = resolve_internal_import(
- mamba_ssm, chained_path="ops.triton.ssd_combined.mamba_chunk_scan_combined"
- )
- mamba_split_conv1d_scan_combined = resolve_internal_import(
- mamba_ssm, chained_path="ops.triton.ssd_combined.mamba_split_conv1d_scan_combined"
- )
- global is_fast_path_available
- is_fast_path_available = all(
- (
- selective_state_update,
- mamba_chunk_scan_combined,
- mamba_split_conv1d_scan_combined,
- causal_conv1d_fn,
- causal_conv1d_update,
- )
- )
- if not is_fast_path_available:
- logger.warning_once(
- "The fast path is not available because one of `(selective_state_update, causal_conv1d_fn, causal_conv1d_update)`"
- " is None. Falling back to the naive implementation. To install follow https://github.com/state-spaces/mamba/#installation and"
- " https://github.com/Dao-AILab/causal-conv1d"
- )
- else:
- logger.warning_once("The fast path for Bamba will be used when running the model on a GPU")
- def cuda_kernels_forward(
- self,
- hidden_states: torch.Tensor,
- cache_params: Cache | None = None,
- attention_mask: torch.Tensor | None = None,
- seq_idx: torch.IntTensor | None = None,
- ):
- # 1. Gated MLP's linear projection
- hidden_states = apply_mask_to_padding_states(hidden_states, attention_mask)
- projected_states = self.in_proj(hidden_states)
- # Set up dimensions for reshapes later
- batch_size, seq_len, _ = hidden_states.shape
- groups_time_state_size = self.n_groups * self.ssm_state_size
- use_precomputed_states = (
- cache_params is not None and cache_params.has_previous_state(self.layer_idx) and seq_len == 1
- )
- # getting projected states from cache if it exists
- if use_precomputed_states:
- gate, hidden_states_B_C, dt = projected_states.squeeze(1).split(
- [self.intermediate_size, self.conv_dim, self.num_heads], dim=-1
- )
- # 2. Convolution sequence transformation
- hidden_states_B_C = causal_conv1d_update(
- hidden_states_B_C,
- cache_params.layers[self.layer_idx].conv_states,
- self.conv1d.weight.squeeze(1),
- self.conv1d.bias,
- self.activation,
- )
- hidden_states, B, C = torch.split(
- hidden_states_B_C,
- [self.intermediate_size, groups_time_state_size, groups_time_state_size],
- dim=-1,
- )
- # 3. SSM transformation
- A = -torch.exp(self.A_log.float()) # (nheads,)
- A = A[:, None, ...][:, :, None].expand(-1, self.head_dim, self.ssm_state_size).to(dtype=torch.float32)
- dt = dt[:, :, None].expand(-1, -1, self.head_dim)
- dt_bias = self.dt_bias[:, None, ...].expand(-1, self.head_dim)
- D = self.D[:, None, ...].expand(-1, self.head_dim)
- B = B.view(batch_size, self.n_groups, B.shape[1] // self.n_groups)
- C = C.view(batch_size, self.n_groups, C.shape[1] // self.n_groups)
- hidden_states_reshaped = hidden_states.view(batch_size, self.num_heads, self.head_dim)
- hidden_states = selective_state_update(
- cache_params.layers[self.layer_idx].recurrent_states,
- hidden_states_reshaped,
- dt,
- A,
- B,
- C,
- D,
- z=None,
- dt_bias=dt_bias,
- dt_softplus=True,
- )
- hidden_states = hidden_states.view(batch_size, self.num_heads * self.head_dim)
- hidden_states = self.norm(hidden_states, gate)
- # 4. Final linear projection
- out = self.out_proj(hidden_states)[:, None, ...]
- # Fused calculations or step by step if no initialized cache is found
- else:
- A = -torch.exp(self.A_log.float()) # (num_heads) or (intermediate_size, state_size)
- dt_limit_kwargs = {} if self.time_step_limit == (0.0, float("inf")) else {"dt_limit": self.time_step_limit}
- # 2-4. Fused kernel for conv1d, SSM, and the final projection
- if self.training and cache_params is None:
- out = mamba_split_conv1d_scan_combined(
- projected_states,
- self.conv1d.weight.squeeze(1),
- self.conv1d.bias,
- self.dt_bias,
- A,
- D=self.D,
- chunk_size=self.chunk_size,
- seq_idx=seq_idx,
- activation=self.activation,
- rmsnorm_weight=self.norm.weight,
- rmsnorm_eps=self.norm.variance_epsilon,
- outproj_weight=self.out_proj.weight,
- outproj_bias=self.out_proj.bias,
- headdim=self.head_dim,
- ngroups=self.n_groups,
- norm_before_gate=False,
- return_final_states=False,
- **dt_limit_kwargs,
- )
- else:
- gate, hidden_states_B_C, dt = projected_states.split(
- [self.intermediate_size, self.conv_dim, self.num_heads], dim=-1
- )
- # 2. Convolution sequence transformation
- # Init cache
- if cache_params is not None:
- # storing the states
- # If we just take xBC[:, :, -self.d_conv :], it will error if seqlen < self.d_conv
- # Instead F.pad will pad with zeros if seqlen < self.d_conv, and truncate otherwise.
- hidden_states_B_C_transposed = hidden_states_B_C.transpose(1, 2)
- conv_states = nn.functional.pad(
- hidden_states_B_C_transposed,
- (self.conv_kernel_size - hidden_states_B_C_transposed.shape[-1], 0),
- )
- conv_states = cache_params.update_conv_state(conv_states, self.layer_idx)
- if self.activation not in ["silu", "swish"]:
- hidden_states_B_C = self.act(
- self.conv1d(hidden_states_B_C.transpose(1, 2))[..., :seq_len].transpose(1, 2)
- )
- else:
- hidden_states_B_C = causal_conv1d_fn(
- x=hidden_states_B_C.transpose(1, 2),
- weight=self.conv1d.weight.squeeze(1),
- bias=self.conv1d.bias,
- activation=self.activation,
- seq_idx=seq_idx,
- ).transpose(1, 2)
- hidden_states_B_C = apply_mask_to_padding_states(hidden_states_B_C, attention_mask)
- hidden_states, B, C = torch.split(
- hidden_states_B_C,
- [self.intermediate_size, groups_time_state_size, groups_time_state_size],
- dim=-1,
- )
- # 3. SSM transformation
- scan_output, ssm_state = mamba_chunk_scan_combined(
- hidden_states.view(batch_size, seq_len, -1, self.head_dim),
- dt,
- A,
- B.view(batch_size, seq_len, self.n_groups, -1),
- C.view(batch_size, seq_len, self.n_groups, -1),
- chunk_size=self.chunk_size,
- D=self.D,
- z=None,
- seq_idx=seq_idx,
- return_final_states=True,
- dt_bias=self.dt_bias,
- dt_softplus=True,
- **dt_limit_kwargs,
- )
- # Init cache
- if ssm_state is not None and cache_params is not None:
- ssm_state = cache_params.update_recurrent_state(ssm_state, self.layer_idx)
- scan_output = scan_output.view(batch_size, seq_len, -1)
- # Multiply "gate" branch and apply extra normalization layer
- scan_output = self.norm(scan_output, gate)
- # 4. Final linear projection
- out = self.out_proj(scan_output)
- return out
- # fmt: off
- def torch_forward(
- self,
- input_states,
- cache_params: Cache | None = None,
- attention_mask: torch.Tensor | None = None,
- ):
- batch_size, seq_len, _ = input_states.shape
- dtype = input_states.dtype
- # 1. Gated MLP's linear projection
- input_states = apply_mask_to_padding_states(input_states, attention_mask)
- projected_states = self.in_proj(input_states)
- gate, hidden_states_B_C, dt = projected_states.split(
- [self.intermediate_size, self.conv_dim, self.num_heads], dim=-1
- )
- hidden_states_B_C = hidden_states_B_C.transpose(1,2)
- use_precomputed_states = cache_params is not None and cache_params.has_previous_state(self.layer_idx) and seq_len == 1
- # 2. Convolution sequence transformation
- if use_precomputed_states:
- conv_states = cache_params.update_conv_state(hidden_states_B_C, self.layer_idx)
- hidden_states_B_C = torch.sum(
- conv_states * self.conv1d.weight.squeeze(1), dim=-1
- )
- if self.use_conv_bias:
- hidden_states_B_C = hidden_states_B_C + self.conv1d.bias
- hidden_states_B_C = self.act(hidden_states_B_C)
- else:
- # Init cache
- if cache_params is not None:
- conv_states = nn.functional.pad(
- hidden_states_B_C, (self.conv_kernel_size - hidden_states_B_C.shape[-1], 0)
- )
- conv_states = cache_params.update_conv_state(conv_states, self.layer_idx)
- hidden_states_B_C = self.act(self.conv1d(hidden_states_B_C)[..., :seq_len].transpose(1, 2))
- hidden_states_B_C = apply_mask_to_padding_states(hidden_states_B_C, attention_mask)
- hidden_states, B, C = torch.split(
- hidden_states_B_C,
- [self.intermediate_size, self.n_groups * self.ssm_state_size, self.n_groups * self.ssm_state_size],
- dim=-1
- )
- # 3. SSM transformation
- A = -torch.exp(self.A_log.float()) # [num_heads]
- if use_precomputed_states:
- # We need to guarantee that anything regarding the cache is on the same device
- cache_device = cache_params.layers[self.layer_idx].recurrent_states.device
- # Note: there is no need to pad parameter matrices here, as there is just one new token
- # for batched generation
- dt = dt[:, 0, :][:, None, ...]
- dt = dt.transpose(1, 2).expand(batch_size, dt.shape[-1], self.head_dim)
- # [num_heads] -> [num_heads, head_dim]
- dt_bias = self.dt_bias[..., None].expand(self.dt_bias.shape[0], self.head_dim)
- dt = torch.nn.functional.softplus(dt + dt_bias.to(dt.dtype))
- dt = torch.clamp(dt, self.time_step_limit[0], self.time_step_limit[1])
- A = A[..., None, None].expand(self.num_heads, self.head_dim, self.ssm_state_size).to(dtype=torch.float32)
- # [bsz, num_heads, head_dim, state_size]
- dA = (torch.exp(dt[..., None] * A)).to(device=cache_device)
- # Discretize B
- # [bsz, n_groups * state_size] -> [bsz, n_groups, 1, state_size] ->
- # -> [bsz, n_groups, group to head repetition factor, state_size] -> [bsz, num_heads, state_size]
- B = B.reshape(batch_size, self.n_groups, -1)[..., None, :]
- B = B.expand(batch_size, self.n_groups, self.num_heads // self.n_groups, B.shape[-1]).contiguous()
- B = B.reshape(batch_size, -1, B.shape[-1])
- # [bsz, num_heads, head_dim, state_size]
- dB = dt[..., None] * B[..., None, :]
- # Discretize x into dB
- # [bsz, intermediate_size] -> [bsz, num_heads, head_dim]
- hidden_states = hidden_states.reshape(batch_size, -1, self.head_dim)
- dBx = (dB * hidden_states[..., None]).to(device=cache_device)
- # State calculation
- ssm_states = cache_params.layers[self.layer_idx].recurrent_states * dA + dBx
- ssm_states = cache_params.update_recurrent_state(ssm_states, self.layer_idx)
- # Subsequent output
- # [bsz, n_groups * state_size] -> [bsz, num_heads, state_size]
- C = C.reshape(batch_size, self.n_groups, -1)[..., None, :]
- C = C.expand(batch_size, self.n_groups, self.num_heads // self.n_groups, C.shape[-1]).contiguous()
- C = C.reshape(batch_size, -1, C.shape[-1])
- # [bsz, num_heads, head_dim]
- ssm_states = ssm_states.to(device=C.device, dtype=C.dtype) # Shape: [b, h, d, n]
- # Reshape ssm_states to merge the first two dimensions
- ssm_states_reshaped = ssm_states.view(batch_size * self.num_heads, self.head_dim, self.ssm_state_size) # Shape: [b*h, d, n]
- C_reshaped = C.view(batch_size * self.num_heads, self.ssm_state_size, 1) # Shape: [b*h, n, 1]
- y = torch.bmm(ssm_states_reshaped, C_reshaped)
- y = y.view(batch_size, self.num_heads, self.head_dim)
- # D skip connection
- # [num_heads] -> [num_heads, head_dim]
- D = self.D[..., None].expand(self.D.shape[0], self.head_dim)
- y = (y + hidden_states * D).to(y.dtype)
- # [bsz, num_heads, head_dim] -> [bsz, 1, intermediate_size]
- y = y.reshape(batch_size, -1)[:, None, ...]
- else:
- # begin ssd naive implementation without einsums
- dt = nn.functional.softplus(dt + self.dt_bias)
- dt = torch.clamp(dt, self.time_step_limit[0], self.time_step_limit[1])
- hidden_states = hidden_states.reshape(batch_size, seq_len, -1, self.head_dim).float()
- B = B.reshape(batch_size, seq_len, -1, self.ssm_state_size).float()
- C = C.reshape(batch_size, seq_len, -1, self.ssm_state_size).float()
- B = B.repeat_interleave(self.num_heads // self.n_groups, dim=2, output_size=self.num_heads)
- C = C.repeat_interleave(self.num_heads // self.n_groups, dim=2, output_size=self.num_heads)
- pad_size = (self.chunk_size - seq_len % self.chunk_size) % self.chunk_size
- D_residual = self.D[..., None] * pad_tensor_by_size(hidden_states, pad_size)
- # Discretize x and A
- hidden_states = hidden_states * dt[..., None]
- A = A.to(hidden_states.dtype) * dt
- # Rearrange into blocks/chunks
- hidden_states, A, B, C = [reshape_into_chunks(t, pad_size, self.chunk_size) for t in (hidden_states, A, B, C)]
- # [bsz, -1, chunk_size, num_heads] -> [bsz, num_heads, -1, chunk_size]
- A = A.permute(0, 3, 1, 2)
- A_cumsum = torch.cumsum(A, dim=-1)
- # 1. Compute the output for each intra-chunk (diagonal blocks)
- # This is the analog of a causal mask
- L = torch.exp(segment_sum(A))
- # Contraction of C and B to get G (attention-weights like)
- G_intermediate = C[:, :, :, None, :, :] * B[:, :, None, :, :, :] # shape: (b, c, l, s, h, n)
- G = G_intermediate.sum(dim=-1) # shape: (b, c, l, s, h)
- # Compute M, equivalent to applying attention mask to weights
- M_intermediate = G[..., None] * L.permute(0, 2, 3, 4, 1)[..., None]
- M = M_intermediate.sum(dim=-1)
- # Compute Y_diag (apply to values)
- Y_diag = (M[..., None] * hidden_states[:, :, None]).sum(dim=3)
- # 2. Compute the state for each intra-chunk
- # (right term of low-rank factorization of off-diagonal blocks; B terms)
- decay_states = torch.exp(A_cumsum[:, :, :, -1:] - A_cumsum)
- B_decay = B * decay_states.permute(0, -2, -1, 1)[..., None]
- states = (B_decay[..., None, :] * hidden_states[..., None]).sum(dim=2)
- # 3. Compute the inter-chunk SSM recurrence; produces correct SSM states at chunk boundaries
- # (middle term of factorization of off-diag blocks; A terms)
- previous_states = torch.zeros_like(states[:, :1])
- states = torch.cat([previous_states, states], dim=1)
- decay_chunk = torch.exp(segment_sum(nn.functional.pad(A_cumsum[:, :, :, -1], (1, 0))))
- decay_chunk = decay_chunk.transpose(1, 3)
- new_states = (decay_chunk[..., None, None] * states[:, :, None, ...]).sum(dim=1)
- states, ssm_state = new_states[:, :-1], new_states[:, -1]
- # 4. Compute state -> output conversion per chunk
- # (left term of low-rank factorization of off-diagonal blocks; C terms)
- state_decay_out = torch.exp(A_cumsum)
- C_times_states = (C[..., None, :] * states[:, :, None, ...])
- state_decay_out_permuted = state_decay_out.permute(0, 2, 3, 1)
- Y_off = (C_times_states.sum(-1) * state_decay_out_permuted[..., None])
- # Add output of intra-chunk and inter-chunk terms (diagonal and off-diagonal blocks)
- y = Y_diag + Y_off
- # [bsz, -1, self.chunk_size, num_heads, head_dim] -> [bsz, (padded) seq_len, num_heads, head_dim]
- y = y.reshape(batch_size, -1, self.num_heads, self.head_dim)
- y = y + D_residual
- # Cutting off padded chunks
- if pad_size > 0:
- y = y[:, :seq_len, :, :]
- y = y.reshape(batch_size, seq_len, -1)
- # Init cache
- if ssm_state is not None and cache_params is not None:
- ssm_state = cache_params.update_recurrent_state(ssm_state, self.layer_idx)
- scan_output = self.norm(y, gate)
- # end ssd naive
- # 4. Final linear projection
- contextualized_states = self.out_proj(scan_output.to(dtype)) # [batch, seq_len, hidden_size]
- return contextualized_states
- # fmt: on
- def forward(
- self,
- hidden_states,
- cache_params: Cache | None = None,
- attention_mask: torch.Tensor | None = None,
- seq_idx: torch.IntTensor | None = None,
- **kwargs,
- ):
- if is_fast_path_available and "cuda" in self.in_proj.weight.device.type and not is_torchdynamo_compiling():
- return self.cuda_kernels_forward(hidden_states, cache_params, attention_mask, seq_idx)
- if seq_idx is not None:
- raise NotImplementedError(
- "`seq_idx` support requires fast path support. Please install `mamba_ssm` and `causal_conv1d`"
- )
- dtype = hidden_states.dtype
- if attention_mask is not None and attention_mask.shape[1] > 1 and attention_mask.shape[0] > 1:
- # tune out hidden states for pad tokens, see https://github.com/state-spaces/mamba/issues/66
- hidden_states = (hidden_states * attention_mask[:, :, None]).to(dtype)
- return self.torch_forward(hidden_states, cache_params, attention_mask)
- class BambaMLP(nn.Module):
- def __init__(self, config):
- super().__init__()
- self.config = config
- self.hidden_size = config.hidden_size
- self.intermediate_size = config.intermediate_size
- self.gate_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=config.mlp_bias)
- self.up_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=config.mlp_bias)
- self.down_proj = nn.Linear(self.intermediate_size, self.hidden_size, bias=config.mlp_bias)
- self.act_fn = ACT2FN[config.hidden_act]
- def forward(self, x):
- down_proj = self.down_proj(self.act_fn(self.gate_proj(x)) * self.up_proj(x))
- return down_proj
- @use_kernel_forward_from_hub("RMSNorm")
- class BambaRMSNorm(nn.Module):
- def __init__(self, hidden_size, eps: float = 1e-6) -> None:
- """
- BambaRMSNorm is equivalent to T5LayerNorm
- """
- super().__init__()
- self.weight = nn.Parameter(torch.ones(hidden_size))
- self.variance_epsilon = eps
- def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
- input_dtype = hidden_states.dtype
- hidden_states = hidden_states.to(torch.float32)
- variance = hidden_states.pow(2).mean(-1, keepdim=True)
- hidden_states = hidden_states * torch.rsqrt(variance + self.variance_epsilon)
- return self.weight * hidden_states.to(input_dtype)
- def extra_repr(self):
- return f"{tuple(self.weight.shape)}, eps={self.variance_epsilon}"
- class BambaDecoderLayer(GradientCheckpointingLayer):
- def __init__(self, config: BambaConfig, layer_idx: int, layer_type: str = "mamba"):
- super().__init__()
- num_experts = 1
- ffn_layer_class = BambaMLP if num_experts == 1 else None
- self.feed_forward = ffn_layer_class(config)
- self.input_layernorm = BambaRMSNorm(config.hidden_size, eps=config.rms_norm_eps)
- self.pre_ff_layernorm = BambaRMSNorm(config.hidden_size, eps=config.rms_norm_eps)
- self.layer_type = layer_type
- if layer_type == "mamba":
- self.mamba = BambaMixer(config=config, layer_idx=layer_idx)
- elif layer_type == "attention":
- self.self_attn = BambaAttention(config, layer_idx)
- else:
- raise ValueError("Invalid layer_type")
- def forward(
- self,
- hidden_states: torch.Tensor,
- attention_mask: torch.Tensor | None = None,
- position_ids: torch.LongTensor | None = None,
- past_key_values: Cache | None = None,
- use_cache: bool | None = False,
- position_embeddings: tuple[torch.Tensor, torch.Tensor] | None = None,
- **kwargs: Unpack[BambaFlashAttentionKwargs],
- ) -> tuple[torch.FloatTensor, tuple[torch.FloatTensor, torch.FloatTensor] | None]:
- residual = hidden_states
- hidden_states = self.input_layernorm(hidden_states)
- if self.layer_type == "mamba":
- hidden_states = self.mamba(
- hidden_states=hidden_states,
- cache_params=past_key_values,
- attention_mask=attention_mask,
- **kwargs,
- )
- self_attn_weights = None
- elif self.layer_type == "attention":
- hidden_states, self_attn_weights = self.self_attn(
- hidden_states=hidden_states,
- attention_mask=attention_mask,
- position_ids=position_ids,
- past_key_values=past_key_values,
- use_cache=use_cache,
- position_embeddings=position_embeddings,
- **kwargs,
- )
- hidden_states = residual + hidden_states
- residual = hidden_states
- hidden_states = self.pre_ff_layernorm(hidden_states)
- hidden_states = self.feed_forward(hidden_states)
- hidden_states = residual + hidden_states
- return hidden_states, self_attn_weights
- @auto_docstring
- class BambaPreTrainedModel(PreTrainedModel):
- config: BambaConfig
- base_model_prefix = "model"
- supports_gradient_checkpointing = True
- _no_split_modules = ["BambaDecoderLayer"]
- _skip_keys_device_placement = "past_key_values"
- _supports_flash_attn = True
- _supports_sdpa = True
- _is_stateful = True
- _can_record_outputs = {
- "hidden_states": BambaDecoderLayer,
- "attentions": BambaAttention,
- }
- @torch.no_grad()
- def _init_weights(self, module):
- super()._init_weights(module)
- if isinstance(module, BambaMixer):
- init.ones_(module.dt_bias)
- init.copy_(module.A_log, torch.log(torch.arange(1, module.num_heads + 1)))
- init.ones_(module.D)
- @auto_docstring
- class BambaModel(BambaPreTrainedModel):
- def __init__(self, config: BambaConfig):
- super().__init__(config)
- self.padding_idx = config.pad_token_id
- self.vocab_size = config.vocab_size
- self.embed_tokens = nn.Embedding(config.vocab_size, config.hidden_size, self.padding_idx)
- decoder_layers = []
- for i in range(config.num_hidden_layers):
- decoder_layers.append(BambaDecoderLayer(config, layer_idx=i, layer_type=config.layers_block_type[i]))
- self.layers = nn.ModuleList(decoder_layers)
- self._attn_implementation = config._attn_implementation
- self.final_layernorm = BambaRMSNorm(config.hidden_size, eps=config.rms_norm_eps)
- self.rotary_emb = BambaRotaryEmbedding(config=config)
- self.gradient_checkpointing = False
- # Initialize weights and apply final processing
- self.post_init()
- @merge_with_config_defaults
- @capture_outputs
- @auto_docstring
- def forward(
- self,
- input_ids: torch.LongTensor | None = None,
- attention_mask: torch.Tensor | None = None,
- position_ids: torch.LongTensor | None = None,
- past_key_values: Cache | None = None,
- inputs_embeds: torch.FloatTensor | None = None,
- use_cache: bool | None = None,
- **kwargs: Unpack[BambaFlashAttentionKwargs],
- ) -> BaseModelOutputWithPast:
- if (input_ids is None) ^ (inputs_embeds is not None):
- raise ValueError("You must specify exactly one of input_ids or inputs_embeds")
- if inputs_embeds is None:
- inputs_embeds = self.embed_tokens(input_ids)
- hidden_states = inputs_embeds
- if use_cache and past_key_values is None:
- past_key_values = DynamicCache(config=self.config)
- if position_ids is None:
- position_ids = torch.arange(hidden_states.shape[1], device=hidden_states.device).unsqueeze(0)
- causal_mask = create_causal_mask(
- config=self.config,
- inputs_embeds=inputs_embeds,
- attention_mask=attention_mask,
- past_key_values=past_key_values,
- position_ids=position_ids,
- )
- mamba_mask = self._update_mamba_mask(attention_mask, past_key_values)
- position_embeddings = self.rotary_emb(hidden_states, position_ids=position_ids)
- for i, decoder_layer in enumerate(self.layers):
- layer_mask = mamba_mask if self.config.layers_block_type[i] == "mamba" else causal_mask
- hidden_states, attn_weights = decoder_layer(
- hidden_states,
- attention_mask=layer_mask,
- position_ids=position_ids,
- past_key_values=past_key_values,
- use_cache=use_cache,
- position_embeddings=position_embeddings,
- **kwargs,
- )
- hidden_states = self.final_layernorm(hidden_states)
- return BaseModelOutputWithPast(
- last_hidden_state=hidden_states,
- past_key_values=past_key_values,
- )
- def _update_mamba_mask(self, attention_mask, past_key_values):
- """
- No need for zeroing states when
- 1. Cached forward
- 2. Attending to all inputs
- """
- mamba_mask = attention_mask
- if (past_key_values is not None and past_key_values.has_previous_state()) or (
- attention_mask is not None and torch.all(attention_mask == 1)
- ):
- mamba_mask = None
- return mamba_mask
- @auto_docstring
- class BambaForCausalLM(BambaPreTrainedModel, GenerationMixin):
- _tied_weights_keys = {"lm_head.weight": "model.embed_tokens.weight"}
- _tp_plan = {"lm_head": "colwise_gather_output"}
- _pp_plan = {"lm_head": (["hidden_states"], ["logits"])}
- def __init__(self, config):
- super().__init__(config)
- self.model = BambaModel(config)
- self.vocab_size = config.vocab_size
- self.lm_head = nn.Linear(config.hidden_size, config.vocab_size, bias=False)
- self.z_loss_coefficient = config.z_loss_coefficient
- # Initialize weights and apply final processing
- self.post_init()
- @can_return_tuple
- @auto_docstring
- def forward(
- self,
- input_ids: torch.LongTensor | None = None,
- attention_mask: torch.Tensor | None = None,
- position_ids: torch.LongTensor | None = None,
- past_key_values: Cache | None = None,
- inputs_embeds: torch.FloatTensor | None = None,
- labels: torch.LongTensor | None = None,
- use_cache: bool | None = None,
- logits_to_keep: int | torch.Tensor = 0,
- **kwargs,
- ) -> CausalLMOutputWithPast:
- r"""
- labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
- Labels for computing the masked language modeling loss. Indices should either be in `[0, ...,
- config.vocab_size]` or -100 (see `input_ids` docstring). Tokens with indices set to `-100` are ignored
- (masked), the loss is only computed for the tokens with labels in `[0, ..., config.vocab_size]`.
- Example:
- ```python
- >>> from transformers import AutoTokenizer, BambaForCausalLM
- >>> model = BambaForCausalLM.from_pretrained("...")
- >>> tokenizer = AutoTokenizer.from_pretrained("...")
- >>> prompt = "Hey, are you conscious? Can you talk to me?"
- >>> inputs = tokenizer(prompt, return_tensors="pt")
- >>> # Generate
- >>> generate_ids = model.generate(inputs.input_ids, max_length=30)
- >>> tokenizer.batch_decode(generate_ids, skip_special_tokens=True, clean_up_tokenization_spaces=False)[0]
- "Hey, are you conscious? Can you talk to me?\nI'm not conscious, but I can talk to you."
- ```"""
- outputs: BaseModelOutputWithPast = self.model(
- input_ids=input_ids,
- attention_mask=attention_mask,
- position_ids=position_ids,
- past_key_values=past_key_values,
- inputs_embeds=inputs_embeds,
- use_cache=use_cache,
- **kwargs,
- )
- hidden_states = outputs.last_hidden_state
- slice_indices = slice(-logits_to_keep, None) if isinstance(logits_to_keep, int) else logits_to_keep
- logits = self.lm_head(hidden_states[:, slice_indices, :])
- loss = None
- if labels is not None:
- loss = self.loss_function(logits=logits, labels=labels, vocab_size=self.config.vocab_size, **kwargs)
- if self.z_loss_coefficient > 0:
- z_loss = logits.logsumexp(dim=-1).to(dtype=loss.dtype).pow(2).mean()
- loss = loss + self.z_loss_coefficient * z_loss
- return CausalLMOutputWithPast(
- loss=loss,
- logits=logits,
- past_key_values=outputs.past_key_values,
- hidden_states=outputs.hidden_states,
- attentions=outputs.attentions,
- )
- def prepare_inputs_for_generation(
- self,
- input_ids,
- past_key_values=None,
- attention_mask=None,
- inputs_embeds=None,
- position_ids=None,
- use_cache=True,
- is_first_iteration=False,
- **kwargs,
- ):
- kwargs["logits_to_keep"] = self.config.num_logits_to_keep
- model_inputs = super().prepare_inputs_for_generation(
- input_ids,
- past_key_values=past_key_values,
- attention_mask=attention_mask,
- inputs_embeds=inputs_embeds,
- position_ids=position_ids,
- use_cache=use_cache,
- is_first_iteration=is_first_iteration,
- **kwargs,
- )
- return model_inputs
- __all__ = ["BambaModel", "BambaForCausalLM", "BambaPreTrainedModel"]
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