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Format flash_attn_interface.py

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This commit is contained in:
Tri Dao 2023-12-19 23:13:53 -08:00
parent 0a146185d6
commit bc28eacc60
1 changed files with 14 additions and 6 deletions
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20
flash_attn/flash_attn_interface.py
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@ -43,7 +43,9 @@ def _get_block_size(device, head_dim, is_dropout, is_causal):
return (128, 64) if is_sm80 else (64, 64)
def _flash_attn_forward(q, k, v, dropout_p, softmax_scale, causal, window_size, alibi_slopes, return_softmax):
def _flash_attn_forward(
q, k, v, dropout_p, softmax_scale, causal, window_size, alibi_slopes, return_softmax
):
maybe_contiguous = lambda x: x.contiguous() if x.stride(-1) != 1 else x
q, k, v = [maybe_contiguous(x) for x in (q, k, v)]
out, q, k, v, out_padded, softmax_lse, S_dmask, rng_state = flash_attn_cuda.fwd(
@ -202,7 +204,9 @@ def _flash_attn_varlen_backward(
class FlashAttnQKVPackedFunc(torch.autograd.Function):
@staticmethod
def forward(ctx, qkv, dropout_p, softmax_scale, causal, window_size, alibi_slopes, return_softmax):
def forward(
ctx, qkv, dropout_p, softmax_scale, causal, window_size, alibi_slopes, return_softmax
):
if softmax_scale is None:
softmax_scale = qkv.shape[-1] ** (-0.5)
out, q, k, v, out_padded, softmax_lse, S_dmask, rng_state = _flash_attn_forward(
@ -322,7 +326,9 @@ class FlashAttnVarlenQKVPackedFunc(torch.autograd.Function):
class FlashAttnKVPackedFunc(torch.autograd.Function):
@staticmethod
def forward(ctx, q, kv, dropout_p, softmax_scale, causal, window_size, alibi_slopes, return_softmax):
def forward(
ctx, q, kv, dropout_p, softmax_scale, causal, window_size, alibi_slopes, return_softmax
):
if softmax_scale is None:
softmax_scale = q.shape[-1] ** (-0.5)
out, q, k, v, out_padded, softmax_lse, S_dmask, rng_state = _flash_attn_forward(
@ -452,7 +458,9 @@ class FlashAttnVarlenKVPackedFunc(torch.autograd.Function):
class FlashAttnFunc(torch.autograd.Function):
@staticmethod
def forward(ctx, q, k, v, dropout_p, softmax_scale, causal, window_size, alibi_slopes, return_softmax):
def forward(
ctx, q, k, v, dropout_p, softmax_scale, causal, window_size, alibi_slopes, return_softmax
):
if softmax_scale is None:
softmax_scale = q.shape[-1] ** (-0.5)
out, q, k, v, out_padded, softmax_lse, S_dmask, rng_state = _flash_attn_forward(
@ -629,7 +637,7 @@ def flash_attn_kvpacked_func(
softmax_scale=None,
causal=False,
window_size=(-1, -1), # -1 means infinite context window
alibi_slopes=None,
alibi_slopes=None,
return_attn_probs=False,
):
"""dropout_p should be set to 0.0 during evaluation
@ -1079,6 +1087,6 @@ def flash_attn_with_kvcache(
window_size[1],
rotary_interleaved,
num_splits,
alibi_slopes
alibi_slopes,
)
return out