Files
AstrAI/astrai/extension/__init__.py
T
ViperEkura 21bf37dd83 refactor: unify extension API to blhd layout and is_causal
- Rename ops.py to attention_ops.py
- Remove layout/scale params: fixed blhd, auto scale
- Replace causal_offset with is_causal bool
- Move SDPA fallback to backend, ops only calls CUDA kernels
- Update __init__.py exports
2026-07-30 18:39:20 +08:00

43 lines
1.2 KiB
Python

"""CUDA attention kernel wrappers with torch fallback.
Public API:
- ``attn_decode`` — single-query decode attention
- ``attn_prefill`` — multi-query prefill attention
- ``attn_paged_decode`` — paged decode attention (direct page-table access)
- ``AttentionBackend`` — ABC for attention computation strategies
- ``TorchNativeBackend`` — default SDPA backend with KV cache I/O
Layout convention: all q/k/v are ``[batch, seq_len, n_heads, head_dim]``
(blhd). Scale is always ``1/sqrt(head_dim)``.
Each wrapper dispatches to its compiled CUDA kernel (``astrai.extension.attn_*``)
when available, otherwise falls back to ``torch.nn.functional.scaled_dot_product_attention``.
"""
from astrai.extension.attention_backend import (
ATTN_BACKEND,
AttentionBackend,
TorchNativeBackend,
attn_backend,
get_backend,
)
from astrai.extension.attention_ops import (
attn_decode,
attn_paged_decode,
attn_prefill,
)
from astrai.extension.loader import KERNEL_NAMES, is_available
__all__ = [
"ATTN_BACKEND",
"AttentionBackend",
"TorchNativeBackend",
"attn_backend",
"get_backend",
"attn_decode",
"attn_paged_decode",
"attn_prefill",
"is_available",
"KERNEL_NAMES",
]