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Mirrored from https://github.com/tduncan-lum/Nvidia-Optimization-Stack---VLLM.git
Synced Nov 15, 11:00 UTC
[Attention] MLA move rotary embedding to cuda-graph region (#17668)
Signed-off-by: Lucas Wilkinson <lwilkinson@neuralmagic.com>
Lucas Wilkinson committed
May 8, 2025 at 23:14 UTC
5e6f93948449b8095e8eef5c3d99a8726e216a44
6 files changed
+35
-121
vllm/attention/backends/mla/common.py
+11
-60
@@ -211,8 +211,6 @@ from vllm.attention.utils.fa_utils import get_flash_attn_version
211
from vllm.model_executor.layers.linear import (ColumnParallelLinear,
212
LinearBase,
213
UnquantizedLinearMethod)
214
-from vllm.model_executor.layers.rotary_embedding import (
215
- DeepseekScalingRotaryEmbedding, RotaryEmbedding)
214
from vllm.multimodal import MultiModalPlaceholderMap
215
from vllm.platforms import current_platform
216
from vllm.triton_utils import HAS_TRITON
@@ -377,7 +375,6 @@ class MLACommonState(AttentionState, Generic[T]):
375
seq_start_loc=None,
376
context_lens_tensor=None,
377
block_tables=self._graph_block_tables[:batch_size],
380
- input_positions=self._positions[:batch_size],
378
head_dim=self.runner.model_config.get_head_size())
379
380
if is_encoder_decoder_model:
@@ -393,7 +390,6 @@ class MLACommonState(AttentionState, Generic[T]):
390
"slot_mapping": attn_metadata.slot_mapping,
391
"seq_lens_tensor": attn_metadata.decode_metadata.seq_lens_tensor,
392
"block_tables": attn_metadata.decode_metadata.block_tables,
396
- "input_positions": attn_metadata.decode_metadata.input_positions,
393
}
394
if is_encoder_decoder_model:
395
raise NotImplementedError(
@@ -405,16 +401,10 @@ class MLACommonState(AttentionState, Generic[T]):
401
input_buffers,
402
attn_metadata,
403
is_encoder_decoder_model: bool = False):
408
- input_positions = attn_metadata.input_positions
409
- num_positions = input_positions.shape[0]
404
input_buffers["seq_lens_tensor"].copy_(
405
attn_metadata.decode_metadata.seq_lens_tensor, non_blocking=True)
406
input_buffers["block_tables"].copy_(
407
attn_metadata.decode_metadata.block_tables, non_blocking=True)
414
- # CUDA graph buffer is padded so only perform a partial copy based on
415
- # num_positions
416
- input_buffers["input_positions"][:num_positions].copy_(
417
- input_positions, non_blocking=True)
408
if is_encoder_decoder_model:
409
raise NotImplementedError(
410
"TritonMLAState does not support encoder/decoder yet")
@@ -456,11 +446,6 @@ class MLACommonMetadata(AttentionMetadata):
446
# TODO(woosuk): Move `use_cuda_graph` out since it's unrelated to attention.
447
use_cuda_graph: bool
448
459
- # New for MLA (compared to FlashAttention)
460
- # Input positions for rotrary embeddings since for MLA the rotary
461
- # position embeddings are applied inside the attention backend
462
- input_positions: torch.Tensor
463
-
449
# NOTE(sang): Definition of context_len, query_len, and seq_len.
450
# |---------- N-1 iteration --------|
451
# |---------------- N iteration ---------------------|
@@ -563,8 +548,6 @@ class MLACommonMetadata(AttentionMetadata):
548
self.context_lens_tensor[:self.num_prefills])
549
block_tables = (None if self.block_tables is None else
550
self.block_tables[:self.num_prefills])
566
- input_positions = (None if self.input_positions is None else
567
- self.input_positions[:self.num_prefill_tokens])
551
552
self._cached_prefill_metadata = self.__class__(
553
# Required by ModelRunner
@@ -578,7 +561,6 @@ class MLACommonMetadata(AttentionMetadata):
561
multi_modal_placeholder_index_maps=None,
562
enable_kv_scales_calculation=False,
563
# MLACommonMetadata
581
- input_positions=input_positions,
564
seq_lens=seq_lens,
565
seq_lens_tensor=seq_lens_tensor,
566
max_query_len=self.max_query_len,
@@ -615,8 +597,6 @@ class MLACommonMetadata(AttentionMetadata):
597
self.seq_lens_tensor[self.num_prefills:])
598
block_tables = (None if self.block_tables is None else
599
self.block_tables[self.num_prefills:])
618
- input_positions = (None if self.input_positions is None else
619
- self.input_positions[self.num_prefill_tokens:])
600
601
self._cached_decode_metadata = self.__class__(
602
# Required by ModelRunner
@@ -646,7 +626,6 @@ class MLACommonMetadata(AttentionMetadata):
626
if self.seq_start_loc is not None else None,
627
context_lens_tensor=None,
628
block_tables=block_tables,
649
- input_positions=input_positions,
629
head_dim=self.head_dim,
630
is_profile_run=self.is_profile_run)
631
return self._cached_decode_metadata
@@ -765,7 +744,6 @@ class MLACommonMetadataBuilder(AttentionMetadataBuilder[T], Generic[T]):
744
self.context_lens: List[int] = []
745
self.block_tables: List[List[int]] = []
746
self.curr_seq_lens: List[int] = []
768
- self.input_positions: List[int] = []
747
self.multimodal_placeholder_maps: Dict[
748
str,
749
MultiModalPlaceholderMap] = defaultdict(MultiModalPlaceholderMap)
@@ -786,13 +764,11 @@ class MLACommonMetadataBuilder(AttentionMetadataBuilder[T], Generic[T]):
764
block_tables = inter_data.block_tables
765
766
for (seq_id, token_len, seq_len, curr_seq_len, query_len, context_len,
789
- curr_sliding_window_block, input_positions) in zip(
767
+ curr_sliding_window_block) in zip(
768
inter_data.seq_ids, [len(t) for t in inter_data.input_tokens],
769
inter_data.orig_seq_lens, inter_data.seq_lens,
770
inter_data.query_lens, inter_data.context_lens,
793
- inter_data.curr_sliding_window_blocks,
794
- inter_data.input_positions):
795
- self.input_positions.extend(input_positions)
771
+ inter_data.curr_sliding_window_blocks):
772
self.context_lens.append(context_len)
773
if is_prompt:
774
self.num_prefills += 1
@@ -912,8 +888,6 @@ class MLACommonMetadataBuilder(AttentionMetadataBuilder[T], Generic[T]):
888
device, self.runner.pin_memory)
889
seq_lens_tensor = async_tensor_h2d(seq_lens, torch.int, device,
890
self.runner.pin_memory)
915
- input_positions = async_tensor_h2d(self.input_positions, torch.long,
916
- device, self.runner.pin_memory)
891
slot_mapping_tensor = async_tensor_h2d(self.slot_mapping, torch.long,
892
device, self.runner.pin_memory)
893
query_start_loc_tensor = async_tensor_h2d(query_start_loc, torch.int32,
@@ -987,7 +961,6 @@ class MLACommonMetadataBuilder(AttentionMetadataBuilder[T], Generic[T]):
961
multi_modal_placeholder_index_maps=None, # Not Attention Related
962
enable_kv_scales_calculation=False,
963
# MLACommonMetadata
990
- input_positions=input_positions,
964
seq_lens=seq_lens,
965
seq_lens_tensor=seq_lens_tensor,
966
max_query_len=max_query_len,
@@ -1033,7 +1006,6 @@ class MLACommonImpl(MLAAttentionImpl[T], Generic[T]):
1006
qk_rope_head_dim: int,
1007
qk_head_dim: int,
1008
v_head_dim: int,
1036
- rotary_emb: RotaryEmbedding,
1009
kv_b_proj: ColumnParallelLinear,
1010
) -> None:
1011
self.num_heads = num_heads
@@ -1048,10 +1020,6 @@ class MLACommonImpl(MLAAttentionImpl[T], Generic[T]):
1020
self.qk_rope_head_dim = qk_rope_head_dim
1021
self.qk_head_dim = qk_head_dim
1022
self.v_head_dim = v_head_dim
1051
-
1052
- self.rotary_emb = rotary_emb
1053
- self.use_yarn_rope = isinstance(rotary_emb,
1054
- DeepseekScalingRotaryEmbedding)
1023
self.kv_b_proj = kv_b_proj
1024
1025
self.triton_fa_func = triton_attention
@@ -1367,41 +1335,15 @@ class MLACommonImpl(MLAAttentionImpl[T], Generic[T]):
1335
has_decode = attn_metadata.decode_metadata is not None
1336
has_prefill = attn_metadata.prefill_metadata is not None
1337
1370
- # Restore head dim (for rotary embedding)
1371
- k_pe = k_pe.unsqueeze(1)
1372
- assert hasattr(attn_metadata, "input_positions")
1373
-
1338
num_prefill_tokens: int = attn_metadata.num_prefill_tokens
1339
q = q.view(-1, self.num_heads, self.qk_head_dim)
1340
1341
decode_q = q[num_prefill_tokens:]
1378
- decode_k_pe = k_pe[num_prefill_tokens:]
1379
- decode_input_positions = \
1380
- attn_metadata.input_positions[num_prefill_tokens:]
1342
1343
prefill_q = q[:num_prefill_tokens]
1344
prefill_k_pe = k_pe[:num_prefill_tokens]
1384
- prefill_input_positions = \
1385
- attn_metadata.input_positions[:num_prefill_tokens]
1345
prefill_k_c_normed = k_c_normed[:num_prefill_tokens]
1346
1388
- if has_decode:
1389
- decode_q_nope, decode_q_pe = decode_q.split(
1390
- [self.qk_nope_head_dim, self.qk_rope_head_dim], dim=-1)
1391
- # Convert from (B, N, P) to (N, B, P)
1392
- decode_q_nope = decode_q_nope.transpose(0, 1)
1393
- # Multiply (N, B, P) x (N, P, L) -> (N, B, L)
1394
- decode_ql_nope = torch.bmm(decode_q_nope, self.W_UK_T)
1395
- # Convert from (N, B, L) to (B, N, L)
1396
- decode_ql_nope = decode_ql_nope.transpose(0, 1)
1397
- decode_q_pe[...], decode_k_pe[...] = self.rotary_emb(
1398
- decode_input_positions, decode_q_pe, decode_k_pe)
1399
-
1400
- if has_prefill:
1401
- prefill_q_pe = prefill_q[..., self.qk_nope_head_dim:]
1402
- prefill_q_pe[...], prefill_k_pe[...] = self.rotary_emb(
1403
- prefill_input_positions, prefill_q_pe, prefill_k_pe)
1404
-
1347
# write the latent and rope to kv cache
1348
if kv_cache.numel() > 0:
1349
ops.concat_and_cache_mla(
@@ -1424,6 +1366,15 @@ class MLACommonImpl(MLAAttentionImpl[T], Generic[T]):
1366
attn_metadata)
1367
1368
if has_decode:
1369
+ decode_q_nope, decode_q_pe = decode_q.split(
1370
+ [self.qk_nope_head_dim, self.qk_rope_head_dim], dim=-1)
1371
+ # Convert from (B, N, P) to (N, B, P)
1372
+ decode_q_nope = decode_q_nope.transpose(0, 1)
1373
+ # Multiply (N, B, P) x (N, P, L) -> (N, B, L)
1374
+ decode_ql_nope = torch.bmm(decode_q_nope, self.W_UK_T)
1375
+ # Convert from (N, B, L) to (B, N, L)
1376
+ decode_ql_nope = decode_ql_nope.transpose(0, 1)
1377
+
1378
output[num_prefill_tokens:] = self._forward_decode(
1379
decode_ql_nope, decode_q_pe, kv_cache, attn_metadata)
1380
vllm/attention/backends/rocm_aiter_mla.py
+2
-4
@@ -148,13 +148,11 @@ class AiterMLAMetadataBuilder(MLACommonMetadataBuilder[AiterMLAMetadata]):
148
block_tables = inter_data.block_tables
149
150
for (seq_id, token_len, seq_len, curr_seq_len, query_len, context_len,
151
- curr_sliding_window_block, input_positions) in zip(
151
+ curr_sliding_window_block) in zip(
152
inter_data.seq_ids, [len(t) for t in inter_data.input_tokens],
153
inter_data.orig_seq_lens, inter_data.seq_lens,
154
inter_data.query_lens, inter_data.context_lens,
155
- inter_data.curr_sliding_window_blocks,
156
- inter_data.input_positions):
157
- self.input_positions.extend(input_positions)
155
+ inter_data.curr_sliding_window_blocks):
156
self.context_lens.append(context_len)
157
if is_prompt:
158
self.num_prefills += 1
vllm/model_executor/layers/rotary_embedding.py
+3
-2
@@ -808,8 +808,9 @@ class DeepseekScalingRotaryEmbedding(RotaryEmbedding):
808
query_pass = query[..., self.rotary_dim:]
809
key_pass = key[..., self.rotary_dim:]
810
811
- self.cos_sin_cache: torch.Tensor = self.cos_sin_cache.to(
812
- positions.device)
811
+ if self.cos_sin_cache.device != positions.device:
812
+ self.cos_sin_cache: torch.Tensor = self.cos_sin_cache.to(
813
+ positions.device)
814
cos_sin = self.cos_sin_cache[torch.add(positions, offsets)
815
if offsets is not None else positions]
816
cos, sin = cos_sin.chunk(2, dim=-1)
vllm/model_executor/models/deepseek_v2.py
+7
-1
@@ -453,7 +453,6 @@ class DeepseekV2MLAAttention(nn.Module):
453
qk_rope_head_dim=self.qk_rope_head_dim,
454
qk_head_dim=self.qk_head_dim,
455
v_head_dim=self.v_head_dim,
456
- rotary_emb=self.rotary_emb,
456
kv_b_proj=self.kv_b_proj,
457
)
458
@@ -475,6 +474,13 @@ class DeepseekV2MLAAttention(nn.Module):
474
[self.kv_lora_rank, self.qk_rope_head_dim], dim=-1)
475
kv_c_normed = self.kv_a_layernorm(kv_c.contiguous())
476
477
+ q = q.view(-1, self.num_local_heads, self.qk_head_dim)
478
+ # Add head dim of 1 to k_pe
479
+ k_pe = k_pe.unsqueeze(1)
480
+
481
+ q[..., self.qk_nope_head_dim:], k_pe = self.rotary_emb(
482
+ positions, q[..., self.qk_nope_head_dim:], k_pe)
483
+
484
attn_out = self.mla_attn(
485
q,
486
kv_c_normed,
vllm/v1/attention/backends/mla/common.py
+11
-51
@@ -204,7 +204,6 @@ from vllm.logger import init_logger
204
from vllm.model_executor.layers.linear import (ColumnParallelLinear,
205
LinearBase,
206
UnquantizedLinearMethod)
207
-from vllm.model_executor.layers.rotary_embedding import RotaryEmbedding
207
from vllm.platforms import current_platform
208
from vllm.utils import cdiv, round_down
209
from vllm.v1.attention.backends.utils import CommonAttentionMetadata
@@ -269,9 +268,6 @@ class MLACommonPrefillMetadata:
268
max_seq_lens: list[int]
269
workspace: torch.Tensor
270
272
- # Input positions for rotrary embeddings since for MLA the rotary
273
- # position embeddings are applied inside the attention backend
274
- input_positions: torch.Tensor
271
block_table: torch.Tensor
272
query_start_loc: torch.Tensor
273
max_query_len: int
@@ -280,9 +276,6 @@ class MLACommonPrefillMetadata:
276
277
@dataclass
278
class MLACommonDecodeMetadata:
283
- # Input positions for rotrary embeddings since for MLA the rotary
284
- # position embeddings are applied inside the attention backend
285
- input_positions: torch.Tensor
279
block_table: torch.Tensor
280
seq_lens: torch.Tensor
281
@@ -443,10 +436,8 @@ class MLACommonMetadataBuilder(Generic[M]):
436
437
return modified_batch
438
446
- def _build_decode(self, input_positions: torch.Tensor,
447
- block_table: torch.Tensor, seq_lens: torch.Tensor):
439
+ def _build_decode(self, block_table: torch.Tensor, seq_lens: torch.Tensor):
440
return MLACommonDecodeMetadata(
449
- input_positions=input_positions,
441
block_table=block_table,
442
seq_lens=seq_lens,
443
)
@@ -464,8 +455,6 @@ class MLACommonMetadataBuilder(Generic[M]):
455
self.runner.input_batch.block_table.get_device_tensor()[:num_reqs])
456
slot_mapping = self.runner.slot_mapping_cpu[:num_actual_tokens].to(
457
device, non_blocking=True).long()
467
- input_positions = self.runner.positions_cpu[:num_actual_tokens].to(
468
- device, non_blocking=True).long()
458
459
query_start_loc = common_attn_metadata.query_start_loc
460
seq_lens = common_attn_metadata.seq_lens
@@ -473,7 +462,6 @@ class MLACommonMetadataBuilder(Generic[M]):
462
prefill_metadata = None
463
if self._num_prefills > 0:
464
reqs_start = self._num_decodes # prefill_start
476
- tokens_start = self._num_decode_tokens
465
466
context_lens_cpu = self.runner.input_batch.\
467
num_computed_tokens_cpu_tensor[reqs_start:num_reqs]
@@ -542,7 +530,6 @@ class MLACommonMetadataBuilder(Generic[M]):
530
self.chunked_prefill_workspace_size
531
532
prefill_metadata = MLACommonPrefillMetadata(
545
- input_positions=input_positions[tokens_start:],
533
block_table=block_table[reqs_start:, ...],
534
query_start_loc=prefill_query_start_loc,
535
max_query_len=max_query_len,
@@ -552,7 +539,6 @@ class MLACommonMetadataBuilder(Generic[M]):
539
decode_metadata = None
540
if self._num_decodes > 0:
541
decode_metadata = self._build_decode(
555
- input_positions=input_positions[:self._num_decode_tokens],
542
block_table=block_table[:self._num_decodes, ...],
543
seq_lens=seq_lens[:self._num_decodes],
544
)
@@ -599,7 +585,6 @@ class MLACommonImpl(MLAAttentionImpl[M], Generic[M]):
585
qk_rope_head_dim: int,
586
qk_head_dim: int,
587
v_head_dim: int,
602
- rotary_emb: RotaryEmbedding,
588
kv_b_proj: ColumnParallelLinear,
589
) -> None:
590
self.num_heads = num_heads
@@ -614,15 +599,6 @@ class MLACommonImpl(MLAAttentionImpl[M], Generic[M]):
599
self.qk_rope_head_dim = qk_rope_head_dim
600
self.qk_head_dim = qk_head_dim
601
self.v_head_dim = v_head_dim
617
-
618
- # Hack for V1 for now to avoid torch library overhead (since we are
619
- # already inside an attention custom op), pull out the forward
620
- # method from the rotary embedding and call it directly
621
- # TODO(lucas): we should probably find a cleaner way to do this
622
- self.rotary_emb = rotary_emb.forward_native
623
- if current_platform.is_cuda():
624
- self.rotary_emb = rotary_emb.forward_cuda
625
-
602
self.kv_b_proj = kv_b_proj
603
self.vllm_flash_attn_version = get_flash_attn_version()
604
@@ -894,9 +870,6 @@ class MLACommonImpl(MLAAttentionImpl[M], Generic[M]):
870
k_c_normed = k_c_normed[:num_actual_toks, ...]
871
k_pe = k_pe[:num_actual_toks, ...]
872
897
- # Restore head dim (for rotary embedding)
898
- k_pe = k_pe.unsqueeze(1)
899
-
873
assert attn_metadata.num_decodes is not None and \
874
attn_metadata.num_prefills is not None and \
875
attn_metadata.num_decode_tokens is not None
@@ -905,35 +878,12 @@ class MLACommonImpl(MLAAttentionImpl[M], Generic[M]):
878
has_prefill = attn_metadata.num_prefills > 0
879
num_decode_tokens = attn_metadata.num_decode_tokens
880
908
- q = q.view(-1, self.num_heads, self.qk_head_dim)
881
decode_q = q[:num_decode_tokens]
910
- decode_k_pe = k_pe[:num_decode_tokens]
882
883
prefill_q = q[num_decode_tokens:]
884
prefill_k_pe = k_pe[num_decode_tokens:]
885
prefill_k_c_normed = k_c_normed[num_decode_tokens:]
886
916
- if has_decode:
917
- assert attn_metadata.decode is not None
918
- decode_q_nope, decode_q_pe = decode_q.split(
919
- [self.qk_nope_head_dim, self.qk_rope_head_dim], dim=-1)
920
- # Convert from (B, N, P) to (N, B, P)
921
- decode_q_nope = decode_q_nope.transpose(0, 1)
922
- # Multiply (N, B, P) x (N, P, L) -> (N, B, L)
923
- decode_ql_nope = torch.bmm(decode_q_nope, self.W_UK_T)
924
- # Convert from (N, B, L) to (B, N, L)
925
- decode_ql_nope = decode_ql_nope.transpose(0, 1)
926
- decode_q_pe[...], decode_k_pe[...] = self.rotary_emb(
927
- attn_metadata.decode.input_positions, decode_q_pe, decode_k_pe)
928
-
929
- if has_prefill:
930
- assert attn_metadata.prefill is not None
931
- prefill_q_pe = prefill_q[..., self.qk_nope_head_dim:]
932
-
933
- prefill_q_pe[...], prefill_k_pe[...] = self.rotary_emb(
934
- attn_metadata.prefill.input_positions, prefill_q_pe,
935
- prefill_k_pe)
936
-
887
# write the latent and rope to kv cache
888
if kv_cache.numel() > 0:
889
ops.concat_and_cache_mla(
@@ -951,6 +901,16 @@ class MLACommonImpl(MLAAttentionImpl[M], Generic[M]):
901
attn_metadata)
902
903
if has_decode:
904
+ assert attn_metadata.decode is not None
905
+ decode_q_nope, decode_q_pe = decode_q.split(
906
+ [self.qk_nope_head_dim, self.qk_rope_head_dim], dim=-1)
907
+ # Convert from (B, N, P) to (N, B, P)
908
+ decode_q_nope = decode_q_nope.transpose(0, 1)
909
+ # Multiply (N, B, P) x (N, P, L) -> (N, B, L)
910
+ decode_ql_nope = torch.bmm(decode_q_nope, self.W_UK_T)
911
+ # Convert from (N, B, L) to (B, N, L)
912
+ decode_ql_nope = decode_ql_nope.transpose(0, 1)
913
+
914
output[:num_decode_tokens] = self._forward_decode(
915
decode_ql_nope, decode_q_pe, kv_cache, attn_metadata)
916
vllm/v1/attention/backends/mla/flashmla.py
+1
-3
@@ -58,8 +58,7 @@ class FlashMLAMetadataBuilder(MLACommonMetadataBuilder[FlashMLAMetadata]):
58
self.num_q_heads = self.runner.model_config.get_num_attention_heads(
59
self.runner.parallel_config)
60
61
- def _build_decode(self, input_positions: torch.Tensor,
62
- block_table: torch.Tensor,
61
+ def _build_decode(self, block_table: torch.Tensor,
62
seq_lens: torch.Tensor) -> FlashMLADecodeMetadata:
63
tile_scheduler_metadata, num_splits = \
64
get_mla_metadata(
@@ -69,7 +68,6 @@ class FlashMLAMetadataBuilder(MLACommonMetadataBuilder[FlashMLAMetadata]):
68
)
69
70
return FlashMLADecodeMetadata(
72
- input_positions=input_positions,
71
block_table=block_table,
72
seq_lens=seq_lens,
73
tile_scheduler_metadata=tile_scheduler_metadata,