A high-throughput and memory-efficient inference and serving engine for LLMs
Mirrored from https://github.com/tduncan-lum/Nvidia-Optimization-Stack---VLLM.git
Synced Nov 15, 19:45 UTC
[V1] Support bad_words in sampler (#13376)
Signed-off-by: 22quinn <33176974+22quinn@users.noreply.github.com> Co-authored-by: Nick Hill <nhill@redhat.com>
22quinn committed
Mar 8, 2025 at 14:50 UTC
eb8b5eb183b8428f7e58adf2559e7a8d9400fc30
13 files changed
+266
-28
tests/test_utils.py
+24
-1
@@ -14,7 +14,7 @@ from vllm.config import ParallelConfig, VllmConfig, set_current_vllm_config
14
from vllm.utils import (FlexibleArgumentParser, MemorySnapshot,
15
PlaceholderModule, StoreBoolean, bind_kv_cache,
16
deprecate_kwargs, get_open_port, memory_profiling,
17
- merge_async_iterators, supports_kw)
17
+ merge_async_iterators, supports_kw, swap_dict_values)
18
19
from .utils import error_on_warning, fork_new_process_for_each_test
20
@@ -449,3 +449,26 @@ def test_placeholder_module_error_handling():
449
with build_ctx():
450
# Test conflict with internal __module attribute
451
_ = placeholder_attr.module
452
+
453
+
454
+@pytest.mark.parametrize(
455
+ "obj,key1,key2",
456
+ [
457
+ # Tests for both keys exist
458
+ ({1: "a", 2: "b"}, 1, 2),
459
+ # Tests for one key does not exist
460
+ ({1: "a", 2: "b"}, 1, 3),
461
+ # Tests for both keys do not exist
462
+ ({1: "a", 2: "b"}, 3, 4),
463
+ ])
464
+def test_swap_dict_values(obj, key1, key2):
465
+ original_obj = obj.copy()
466
+ swap_dict_values(obj, key1, key2)
467
+ if key1 in original_obj:
468
+ assert obj[key2] == original_obj[key1]
469
+ else:
470
+ assert key2 not in obj
471
+ if key2 in original_obj:
472
+ assert obj[key1] == original_obj[key2]
473
+ else:
474
+ assert key1 not in obj
tests/v1/sample/test_rejection_sampler.py
+1
@@ -42,6 +42,7 @@ def create_sampling_metadata(spec_tokens: list[list[int]]) -> SamplingMetadata:
42
min_tokens={},
43
logit_bias=[None] * batch_size,
44
allowed_token_ids_mask=None,
45
+ bad_words_token_ids={},
46
)
47
48
tests/v1/sample/test_sampler.py
+76
@@ -77,6 +77,49 @@ def _create_allowed_token_ids(
77
return mask
78
79
80
+def _create_bad_words_token_ids(
81
+ batch_size: int, vocab_size: int,
82
+ bad_words_lengths: list[tuple[int]]) -> dict[int, list[list[int]]]:
83
+ bad_words_token_ids = {}
84
+ for batch_idx in range(batch_size):
85
+ token_ids_single_batch = []
86
+ for bad_words_length in bad_words_lengths:
87
+ token_ids = np.random.choice(vocab_size,
88
+ size=bad_words_length,
89
+ replace=True).tolist()
90
+ token_ids_single_batch.append(token_ids)
91
+ bad_words_token_ids[batch_idx] = token_ids_single_batch
92
+ if batch_size >= 2:
93
+ # Test no bad_words for some batch
94
+ no_bad_words_batch_idx = np.random.choice(batch_size)
95
+ bad_words_token_ids.pop(no_bad_words_batch_idx, None)
96
+ return bad_words_token_ids
97
+
98
+
99
+def _update_output_token_ids_for_bad_words(
100
+ metadata: SamplingMetadata, vocab_size: int) -> dict[int, list[int]]:
101
+ bad_words_last_tokens = {}
102
+ for batch_idx, bad_words_token_ids in metadata.bad_words_token_ids.items():
103
+ output_token_ids = metadata.output_token_ids[batch_idx]
104
+ bad_words_last_token: list[int] = []
105
+ for i, bad_word_token_ids in enumerate(bad_words_token_ids):
106
+ if len(bad_word_token_ids) == 1:
107
+ # Single token id always affects logits
108
+ bad_words_last_token.append(bad_word_token_ids[0])
109
+ else:
110
+ prefix_length = len(bad_word_token_ids) - 1
111
+ has_bad_words = np.random.choice([True, False])
112
+ if has_bad_words:
113
+ output_token_ids[-prefix_length:] = bad_word_token_ids[:-1]
114
+ bad_words_last_token.append(bad_word_token_ids[-1])
115
+ break # Maximum one update to output_token_ids
116
+ else: # Make sure no accidental match to bad words
117
+ output_token_ids[-1] = (bad_word_token_ids[-2] +
118
+ 1) % vocab_size
119
+ bad_words_last_tokens[batch_idx] = bad_words_last_token
120
+ return bad_words_last_tokens
121
+
122
+
123
def _create_default_sampling_metadata(
124
num_output_tokens: int,
125
batch_size: int,
@@ -112,6 +155,7 @@ def _create_default_sampling_metadata(
155
min_tokens={},
156
logit_bias=[None] * batch_size,
157
allowed_token_ids_mask=None,
158
+ bad_words_token_ids={},
159
)
160
return fake_sampling_metadata
161
@@ -467,3 +511,35 @@ def test_sampler_allowed_token_ids(device: str, batch_size: int,
511
"inf"), f"{batch_idx}, {token_id}"
512
else:
513
assert logits_for_req[token_id] != -float("inf")
514
+
515
+
516
+@pytest.mark.parametrize("device", CUDA_DEVICES)
517
+@pytest.mark.parametrize("batch_size", [1, 2, 32])
518
+@pytest.mark.parametrize("bad_words_lengths", [(1, ), (1, 3), (2, 2)])
519
+def test_sampler_bad_words(device: str, batch_size: int,
520
+ bad_words_lengths: list[tuple[int]]):
521
+ """
522
+ Test to verify that when the bad words restriction is present, tokens
523
+ are penalized based on their match with the bad words.
524
+ """
525
+ torch.set_default_device(device)
526
+ # Create fake logits where each token is assigned the same
527
+ # logit value.
528
+ fake_logits = _create_fake_logits(batch_size, VOCAB_SIZE)
529
+ sampling_metadata = _create_default_sampling_metadata(
530
+ NUM_OUTPUT_TOKENS, batch_size, VOCAB_SIZE, torch.device(device))
531
+ sampling_metadata.bad_words_token_ids = _create_bad_words_token_ids(
532
+ batch_size, VOCAB_SIZE, bad_words_lengths)
533
+ bad_words_last_tokens = _update_output_token_ids_for_bad_words(
534
+ sampling_metadata, VOCAB_SIZE)
535
+ sampler = Sampler()
536
+ logits = sampler.apply_bad_words(fake_logits, sampling_metadata)
537
+ logits = logits.cpu()
538
+ for batch_idx in range(batch_size):
539
+ logits_for_req = logits[batch_idx]
540
+ for token_id in range(VOCAB_SIZE):
541
+ if (batch_idx in bad_words_last_tokens
542
+ and token_id in bad_words_last_tokens[batch_idx]):
543
+ assert logits_for_req[token_id] == -float("inf")
544
+ else:
545
+ assert logits_for_req[token_id] != -float("inf")
tests/v1/sample/test_sampling_params_e2e.py
+16
-2
@@ -120,8 +120,22 @@ def test_detokenize_false(model):
120
def test_bad_words(model):
121
"""Check that we respect bad words."""
122
123
- with pytest.raises(ValueError):
124
- _ = model.generate(PROMPT, SamplingParams(bad_words=["Hello"]))
123
+ output = model.generate(PROMPT, SamplingParams(temperature=0))
124
+ split_text = output[0].outputs[0].text.split()
125
+
126
+ bad_words_1 = " ".join(split_text[:2])
127
+ params = SamplingParams(temperature=0, bad_words=[bad_words_1])
128
+ output = model.generate(PROMPT, params)
129
+ new_text = output[0].outputs[0].text
130
+ assert bad_words_1 not in new_text
131
+
132
+ bad_words_2 = new_text.split()[-1]
133
+ params = SamplingParams(temperature=0,
134
+ bad_words=[bad_words_1, bad_words_2])
135
+ output = model.generate(PROMPT, params)
136
+ new_text = output[0].outputs[0].text
137
+ assert bad_words_1 not in new_text
138
+ assert bad_words_2 not in new_text
139
140
141
def test_logits_processor(model):
tests/v1/worker/test_gpu_input_batch.py
+6
@@ -100,6 +100,7 @@ def _construct_expected_sampling_metadata(
100
VOCAB_SIZE,
101
dtype=torch.bool,
102
device=device)
103
+ bad_words_token_ids = {}
104
for req in reqs:
105
if req.req_id not in req_ids_retained:
106
continue
@@ -123,6 +124,8 @@ def _construct_expected_sampling_metadata(
124
if req.sampling_params.allowed_token_ids:
125
allowed_token_ids_mask[index_in_input_batch][
126
req.sampling_params.allowed_token_ids] = True
127
+ bad_words_token_ids[
128
+ index_in_input_batch] = req.sampling_params.bad_words_token_ids
129
130
return SamplingMetadata(
131
temperature=torch.tensor(temperature, dtype=torch.float,
@@ -159,6 +162,7 @@ def _construct_expected_sampling_metadata(
162
and all(x == 1 for x in repetition_penalties)),
163
logit_bias=logit_bias,
164
allowed_token_ids_mask=allowed_token_ids_mask,
165
+ bad_words_token_ids=bad_words_token_ids,
166
)
167
168
@@ -284,6 +288,8 @@ def test_sampling_metadata_in_input_batch(device: str, batch_size: int):
288
assert torch.allclose(
289
expected_sampling_metadata.allowed_token_ids_mask,
290
sampling_metadata.allowed_token_ids_mask)
291
+ assert expected_sampling_metadata.bad_words_token_ids == \
292
+ sampling_metadata.bad_words_token_ids
293
294
295
@pytest.mark.parametrize("device", CUDA_DEVICES)
vllm/sampling_params.py
+51
-1
@@ -11,6 +11,8 @@ from pydantic import BaseModel
11
12
from vllm.logger import init_logger
13
from vllm.logits_process import LogitsProcessor
14
+from vllm.transformers_utils.tokenizer import AnyTokenizer
15
+from vllm.transformers_utils.tokenizers.mistral import MistralTokenizer
16
17
logger = init_logger(__name__)
18
@@ -202,7 +204,6 @@ class SamplingParams(
204
seed: Optional[int] = None
205
stop: Optional[Union[str, list[str]]] = None
206
stop_token_ids: Optional[list[int]] = None
205
- bad_words: Optional[list[str]] = None
207
ignore_eos: bool = False
208
max_tokens: Optional[int] = 16
209
min_tokens: int = 0
@@ -232,6 +233,10 @@ class SamplingParams(
233
allowed_token_ids: Optional[list[int]] = None
234
extra_args: Optional[dict[str, Any]] = None
235
236
+ # Fields used for bad words
237
+ bad_words: Optional[list[str]] = None
238
+ _bad_words_token_ids: list[list[int]] = msgspec.field(default_factory=list)
239
+
240
@staticmethod
241
def from_optional(
242
n: Optional[int] = 1,
@@ -464,6 +469,46 @@ class SamplingParams(
469
eos_ids.update(self.stop_token_ids)
470
self.stop_token_ids = list(eos_ids)
471
472
+ def update_from_tokenizer(self, tokenizer: AnyTokenizer) -> None:
473
+ if self.bad_words is None:
474
+ return
475
+ for bad_word in self.bad_words:
476
+ # To prohibit words both at the beginning
477
+ # and in the middle of text
478
+ # (related to add_prefix_space tokenizer parameter)
479
+ for add_prefix_space in [False, True]:
480
+ prefix = " " if add_prefix_space else ""
481
+ prompt = prefix + bad_word.lstrip()
482
+
483
+ if isinstance(tokenizer, MistralTokenizer):
484
+ # Mistral tokenizers should not add special tokens
485
+ prompt_token_ids = tokenizer.encode(text=prompt)
486
+ else:
487
+ prompt_token_ids = tokenizer.encode(
488
+ text=prompt, add_special_tokens=False)
489
+
490
+ # If no space at the beginning
491
+ # or if prefix space produces a new word token
492
+ if (not add_prefix_space) or (
493
+ add_prefix_space and prompt_token_ids[0]
494
+ != self._bad_words_token_ids[-1][0]
495
+ and len(prompt_token_ids) == len(
496
+ self._bad_words_token_ids[-1])):
497
+ self._bad_words_token_ids.append(prompt_token_ids)
498
+
499
+ invalid_token_ids = [
500
+ token_id for bad_words_token_ids in self._bad_words_token_ids
501
+ for token_id in bad_words_token_ids
502
+ if token_id < 0 or token_id > tokenizer.max_token_id
503
+ ]
504
+ if len(invalid_token_ids) > 0:
505
+ raise ValueError(
506
+ f"The model vocabulary size is {tokenizer.max_token_id+1},"
507
+ f" but the following tokens"
508
+ f" were specified as bad: {invalid_token_ids}."
509
+ f" All token id values should be integers satisfying:"
510
+ f" 0 <= token_id <= {tokenizer.max_token_id}.")
511
+
512
@cached_property
513
def sampling_type(self) -> SamplingType:
514
if self.temperature < _SAMPLING_EPS:
@@ -476,6 +521,11 @@ class SamplingParams(
521
def all_stop_token_ids(self) -> set[int]:
522
return self._all_stop_token_ids
523
524
+ @property
525
+ def bad_words_token_ids(self) -> list[list[int]]:
526
+ # For internal use only. Backward compatibility not guaranteed
527
+ return self._bad_words_token_ids
528
+
529
def clone(self) -> "SamplingParams":
530
"""Deep copy, but maybe not the LogitsProcessor objects.
531
vllm/utils.py
+16
@@ -2361,3 +2361,19 @@ class LazyLoader(types.ModuleType):
2361
if self._module is None:
2362
self._module = self._load()
2363
return dir(self._module)
2364
+
2365
+
2366
+def swap_dict_values(obj: dict[_K, _V], key1: _K, key2: _K) -> None:
2367
+ """
2368
+ Helper function to swap values for two keys
2369
+ """
2370
+ v1 = obj.get(key1)
2371
+ v2 = obj.get(key2)
2372
+ if v1 is not None:
2373
+ obj[key2] = v1
2374
+ else:
2375
+ obj.pop(key2, None)
2376
+ if v2 is not None:
2377
+ obj[key1] = v2
2378
+ else:
2379
+ obj.pop(key1, None)
vllm/v1/engine/processor.py
+2
-3
@@ -94,9 +94,6 @@ class Processor:
94
# Best of not yet supported.
95
if params.best_of is not None and params.best_of > 1:
96
raise ValueError("VLLM V1 does not yet support best_of.")
97
- # Bad words not yet supported.
98
- if params.bad_words:
99
- raise ValueError("VLLM V1 does not yet support bad_words.")
97
# Logits processors not supported.
98
if params.logits_processors:
99
raise ValueError("VLLM V1 does not support per request "
@@ -203,6 +200,8 @@ class Processor:
200
sampling_params = params.clone()
201
sampling_params.update_from_generation_config(
202
self.generation_config_fields, eos_token_id)
203
+ sampling_params.update_from_tokenizer(
204
+ self.tokenizer.get_lora_tokenizer(lora_request))
205
206
# Multimodal related.
207
# Compute MM hashes (if enabled)
vllm/v1/sample/metadata.py
+3
@@ -38,3 +38,6 @@ class SamplingMetadata:
38
# `allowed_token_ids_mask` is a 2D bool tensor of shape (max batch size,
39
# vocab size).
40
allowed_token_ids_mask: Optional[torch.Tensor]
41
+
42
+ # req_index -> bad_words_token_ids
43
+ bad_words_token_ids: dict[int, list[list[int]]]
vllm/v1/sample/ops/bad_words.py
new
+38
@@ -0,0 +1,38 @@
1
+# SPDX-License-Identifier: Apache-2.0
2
+
3
+import torch
4
+
5
+_SMALLEST_LOGIT = float("-inf")
6
+
7
+
8
+def _apply_bad_words_single_batch(
9
+ logits: torch.Tensor,
10
+ bad_words_token_ids: list[list[int]],
11
+ past_tokens_ids: list[int],
12
+) -> None:
13
+ for bad_word_ids in bad_words_token_ids:
14
+ if len(bad_word_ids) > len(past_tokens_ids) + 1:
15
+ continue
16
+
17
+ prefix_length = len(bad_word_ids) - 1
18
+ last_token_id = bad_word_ids[-1]
19
+ if prefix_length > 0:
20
+ actual_prefix = past_tokens_ids[-prefix_length:]
21
+ else:
22
+ actual_prefix = []
23
+ expected_prefix = bad_word_ids[:prefix_length]
24
+
25
+ assert len(actual_prefix) == len(expected_prefix)
26
+
27
+ if actual_prefix == expected_prefix:
28
+ logits[last_token_id] = _SMALLEST_LOGIT
29
+
30
+
31
+def apply_bad_words(
32
+ logits: torch.Tensor,
33
+ bad_words_token_ids: dict[int, list[list[int]]],
34
+ past_tokens_ids: list[list[int]],
35
+) -> None:
36
+ for i, bad_words_ids in bad_words_token_ids.items():
37
+ _apply_bad_words_single_batch(logits[i], bad_words_ids,
38
+ past_tokens_ids[i])
vllm/v1/sample/sampler.py
+16
@@ -6,6 +6,7 @@ import torch.nn as nn
6
7
from vllm.v1.outputs import LogprobsTensors, SamplerOutput
8
from vllm.v1.sample.metadata import SamplingMetadata
9
+from vllm.v1.sample.ops.bad_words import apply_bad_words
10
from vllm.v1.sample.ops.penalties import (apply_all_penalties,
11
apply_min_token_penalties)
12
from vllm.v1.sample.ops.topk_topp_sampler import TopKTopPSampler
@@ -38,6 +39,8 @@ class Sampler(nn.Module):
39
logits = logits.to(torch.float32)
40
# Apply allowed token ids.
41
logits = self.apply_allowed_token_ids(logits, sampling_metadata)
42
+ # Apply bad words exclusion.
43
+ logits = self.apply_bad_words(logits, sampling_metadata)
44
# Apply logits bias.
45
logits = self.apply_logits_bias(logits, sampling_metadata)
46
# Apply penalties (e.g., min_tokens, freq_penalties).
@@ -237,3 +240,16 @@ class Sampler(nn.Module):
240
logits.masked_fill_(sampling_metadata.allowed_token_ids_mask,
241
float("-inf"))
242
return logits
243
+
244
+ def apply_bad_words(
245
+ self,
246
+ logits: torch.Tensor,
247
+ sampling_metadata: SamplingMetadata,
248
+ ) -> torch.Tensor:
249
+ if sampling_metadata.bad_words_token_ids:
250
+ apply_bad_words(
251
+ logits,
252
+ sampling_metadata.bad_words_token_ids,
253
+ sampling_metadata.output_token_ids,
254
+ )
255
+ return logits
vllm/v1/worker/gpu_input_batch.py
+16
-21
@@ -10,6 +10,7 @@ import torch
10
from vllm.lora.request import LoRARequest
11
from vllm.multimodal import MultiModalKwargs
12
from vllm.sampling_params import SamplingParams, SamplingType
13
+from vllm.utils import swap_dict_values
14
from vllm.v1.sample.metadata import SamplingMetadata
15
from vllm.v1.utils import copy_slice
16
from vllm.v1.worker.block_table import BlockTable
@@ -204,6 +205,9 @@ class InputBatch:
205
self.allowed_token_ids_mask: Optional[torch.Tensor] = None
206
self.allowed_token_ids_mask_cpu_tensor: Optional[torch.Tensor] = None
207
208
+ # req_index -> bad_words_token_ids
209
+ self.bad_words_token_ids: dict[int, list[list[int]]] = {}
210
+
211
self.req_output_token_ids: list[Optional[list[int]]] = []
212
213
# This is updated each time the batch constituents change.
@@ -320,6 +324,9 @@ class InputBatch:
324
self.allowed_token_ids_mask_cpu_tensor[req_index][
325
sampling_params.allowed_token_ids] = False
326
327
+ self.bad_words_token_ids[
328
+ req_index] = sampling_params.bad_words_token_ids
329
+
330
# Add request lora ID
331
if request.lora_request:
332
lora_id = request.lora_request.lora_int_id
@@ -369,6 +376,7 @@ class InputBatch:
376
if self.allowed_token_ids_mask_cpu_tensor is not None:
377
# False means we don't fill with -inf.
378
self.allowed_token_ids_mask_cpu_tensor[req_index].fill_(False)
379
+ self.bad_words_token_ids.pop(req_index, None)
380
return req_index
381
382
def swap_states(self, i1: int, i2: int) -> None:
@@ -413,27 +421,9 @@ class InputBatch:
421
self.token_ids_cpu[i1, ...] = self.token_ids_cpu[i2, ...]
422
self.token_ids_cpu[i2, ...] = tmp
423
416
- g1 = self.generators.get(i1)
417
- g2 = self.generators.get(i2)
418
- if g1 is not None:
419
- self.generators[i2] = g1
420
- else:
421
- self.generators.pop(i2, None)
422
- if g2 is not None:
423
- self.generators[i1] = g2
424
- else:
425
- self.generators.pop(i1, None)
426
-
427
- t1 = self.min_tokens.get(i1)
428
- t2 = self.min_tokens.get(i2)
429
- if t1 is not None:
430
- self.min_tokens[i2] = t1
431
- else:
432
- self.min_tokens.pop(i2, None)
433
- if t2 is not None:
434
- self.min_tokens[i1] = t2
435
- else:
436
- self.min_tokens.pop(i1, None)
424
+ swap_dict_values(self.generators, i1, i2)
425
+ swap_dict_values(self.min_tokens, i1, i2)
426
+ swap_dict_values(self.bad_words_token_ids, i1, i2)
427
428
self.request_lora_mapping[i1], self.request_lora_mapping[i2] =\
429
self.request_lora_mapping[i2], self.request_lora_mapping[i1]
@@ -518,6 +508,10 @@ class InputBatch:
508
empty_index] = self.allowed_token_ids_mask_cpu_tensor[
509
last_req_index]
510
511
+ bad_words_token_ids = self.bad_words_token_ids.pop(
512
+ last_req_index, None)
513
+ if bad_words_token_ids is not None:
514
+ self.bad_words_token_ids[empty_index] = bad_words_token_ids
515
# Decrement last_req_index since it is now empty.
516
last_req_index -= 1
517
@@ -585,6 +579,7 @@ class InputBatch:
579
no_penalties=self.no_penalties,
580
logit_bias=self.logit_bias[:num_reqs],
581
allowed_token_ids_mask=allowed_token_ids_mask,
582
+ bad_words_token_ids=self.bad_words_token_ids,
583
)
584
585
def _make_prompt_token_ids_tensor(self) -> torch.Tensor:
vllm/v1/worker/gpu_model_runner.py
+1
@@ -1268,6 +1268,7 @@ class GPUModelRunner(LoRAModelRunnerMixin):
1268
min_tokens={},
1269
logit_bias=[None for _ in range(num_reqs)],
1270
allowed_token_ids_mask=None,
1271
+ bad_words_token_ids={},
1272
)
1273
sampler_output = self.model.sample(logits=logits,
1274
sampling_metadata=dummy_metadata)