🚨🚨[core] Completely rewrite the masking logic for all attentions (#37866)
* start * start having a clean 4d mask primitive * Update mask_utils.py * Update mask_utils.py * switch name * Update masking_utils.py * add a new AttentionMask tensor class * fix import * nits * fixes * use full and quandrants * general sdpa mask for all caches * style * start some tests * tests with sliding, chunked * add styling * test hybrid * Update masking_utils.py * small temp fixes * Update modeling_gemma2.py * compile compatible * Update masking_utils.py * improve * start making it more general * Update masking_utils.py * generate * make it work with flex style primitives! * Update masking_utils.py * Update masking_utils.py * Update masking_utils.py * improve * Update cache_utils.py * Update masking_utils.py * simplify - starting to look good! * Update masking_utils.py * name * Update masking_utils.py * style * Update masking_utils.py * Update masking_utils.py * Update masking_utils.py * Update masking_utils.py * small fix for flex * flex compile * FA2 * Update masking_utils.py * Escape for TGI/vLLM! * Update masking_utils.py * Update masking_utils.py * Update masking_utils.py * General case without cache * rename * full test on llama4 * small fix for FA2 guard with chunk * Update modeling_gemma2.py * post rebase cleanup * FA2 supports static cache! * Update modeling_flash_attention_utils.py * Update flex_attention.py * Update masking_utils.py * Update masking_utils.py * Update utils.py * override for export * Update executorch.py * Update executorch.py * Update executorch.py * Update executorch.py * Update masking_utils.py * Update masking_utils.py * output attentions * style * Update masking_utils.py * Update executorch.py * Add doicstring * Add license and put mask visualizer at the end * Update test_modeling_common.py * fix broken test * Update test_modeling_gemma.py * Update test_modeling_gemma2.py * Use fullgraph=False with FA2 * Update utils.py * change name * Update masking_utils.py * improve doc * change name * Update modeling_attn_mask_utils.py * more explicit logic based on model's property * pattern in config * extend * fixes * make it better * generalize to other test models * fix * Update masking_utils.py * fix * do not check mask equivalence if layer types are different * executorch * Update modeling_gemma2.py * Update masking_utils.py * use layer_idx instead * adjust * Update masking_utils.py * test * fix imports * Update modeling_gemma2.py * other test models * Update modeling_llama4.py * Update masking_utils.py * improve * simplify * Update masking_utils.py * typos * typo * fix * Update masking_utils.py * default DynamicCache * remove default cache * simplify * Update masking_utils.py * Update masking_utils.py * Update masking_utils.py * Update masking_utils.py * simplify * Update masking_utils.py * Update masking_utils.py * Update masking_utils.py * export * Update executorch.py * Update executorch.py * Update flex_attention.py * Update executorch.py * upstream to modular gemma 1 & 2 * Update modular_mistral.py * switch names * use dict * put it in the Layer directly * update copy model source for mask functions * apply so many modular (hopefully 1 shot) * use explicite dicts for make style happy * protect import * check docstring * better default in hybrid caches * qwens * Update modular_qwen2.py * simplify core logic! * Update executorch.py * qwen3 moe * Update masking_utils.py * Update masking_utils.py * simplify a lot sdpa causal skip * Update masking_utils.py * post-rebase * gemma3 finally * style * check it before * gemma3 * More general with newer torch * align gemma3 * Update utils.py * Update utils.py * Update masking_utils.py * Update test_modeling_common.py * Update flex_attention.py * Update flex_attention.py * Update flex_attention.py * test * executorch * Update test_modeling_common.py * Update masking_utils.py * Update masking_utils.py * Update masking_utils.py * Update masking_utils.py * Update executorch.py * Update test_modeling_common.py * fix copies * device * sdpa can be used without mask -> pass the torchscript tests in this case * Use enum for check * revert enum and add check instead * remove broken test * cohere2 * some doc & reorganize the Interface * Update tensor_parallel.py * Update tensor_parallel.py * doc and dummy * Update test_modeling_paligemma2.py * Update modeling_falcon_h1.py * Update masking_utils.py * executorch patch * style * CIs * use register in executorch * final comments! --------- Co-authored-by: Arthur Zucker <arthur.zucker@gmail.com>
This commit is contained in:
@@ -125,4 +125,44 @@ would expect from a usual Python dictionary:
|
||||
|
||||
# You can also globally `register` a new function directly on it
|
||||
>>> ALL_ATTENTION_FUNCTIONS.register("new_func", new_func)
|
||||
```
|
||||
```
|
||||
|
||||
## Attention Mask Interface
|
||||
|
||||
Having a new attention function may mean that you need a new format of attention mask to decide what key and value tokens
|
||||
the query tokens should attend to. This is now possible with the `AttentionMaskInterface`! It works in the same way as
|
||||
the `AttentionInterface`:
|
||||
|
||||
```python
|
||||
from transformers import AttentionMaskInterface
|
||||
from transformers.masking_utils import sdpa_mask
|
||||
import torch
|
||||
|
||||
def my_new_sdpa_mask(*args, **kwargs):
|
||||
print("I just entered the attention mask computation")
|
||||
return sdpa_mask(*args, **kwargs)
|
||||
|
||||
AttentionMaskInterface.register("my_new_sdpa_mask", my_new_sdpa_mask)
|
||||
```
|
||||
|
||||
The reason you have to register it is because we need to automatically correct your mask format based on the attention implementation (for example, flex attention uses a BlockMask format, while sdpa uses a 4D tensor).
|
||||
By default, if you do not register an attention mask function along with your attention function, mask creation will be skipped
|
||||
and `attention_mask=None` will be passed along to the Attention layers.
|
||||
|
||||
The default signature of the attention mask functions is the following:
|
||||
|
||||
```python
|
||||
def custom_attention_mask(
|
||||
batch_size: int, # required arg
|
||||
cache_position: torch.Tensor, # required arg
|
||||
kv_length: int, # required arg
|
||||
kv_offset: int = 0, # required arg
|
||||
mask_function: Callable = causal_mask_function, # required arg
|
||||
attention_mask: Optional[torch.Tensor] = None, # required arg
|
||||
**kwargs, # a few additional args may be passed as kwargs, especially the model's config is always passed
|
||||
) -> Optional[torch.Tensor]:
|
||||
```
|
||||
|
||||
It mostly works thanks to the `mask_function`, which is a `Callable` in the form of [torch's mask_mod functions](https://pytorch.org/blog/flexattention/), taking 4 indices as input and returning a boolean to indicate if this position should take part in the attention computation.
|
||||
|
||||
If you cannot use the `mask_function` to create your mask for some reason, you can try to work around it by doing something similar to our [torch export workaround](https://github.com/huggingface/transformers/blob/main/src/transformers/integrations/executorch.py).
|
||||
@@ -29,6 +29,11 @@ Most of those are only useful if you are studying the code of the models in the
|
||||
[[autodoc]] AttentionInterface
|
||||
- register
|
||||
|
||||
## Attention Mask Functions
|
||||
|
||||
[[autodoc]] AttentionMaskInterface
|
||||
- register
|
||||
|
||||
## Rotary Position Embedding Functions
|
||||
|
||||
[[autodoc]] dynamic_rope_update
|
||||
|
||||
Reference in New Issue
Block a user