Files
2026-04-09 11:23:47 +08:00

312 lines
10 KiB
Python

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project
import numpy as np
import torch
from vllm.sampling_params import SamplingParams
from vllm.triton_utils import tl, triton
from vllm.utils.math_utils import cdiv
from vllm.utils.torch_utils import async_tensor_h2d
from vllm.v1.worker.gpu.buffer_utils import UvaBackedTensor
from vllm.v1.worker.gpu.states import RequestState
class PenaltiesState:
def __init__(self, req_states: RequestState):
self.req_states = req_states
max_num_reqs = req_states.max_num_reqs
self.vocab_size = req_states.vocab_size
self.device = req_states.device
self.repetition_penalty = UvaBackedTensor(max_num_reqs, dtype=torch.float32)
self.frequency_penalty = UvaBackedTensor(max_num_reqs, dtype=torch.float32)
self.presence_penalty = UvaBackedTensor(max_num_reqs, dtype=torch.float32)
self.use_penalty = np.zeros(max_num_reqs, dtype=bool)
# Initialize repetition penalty manually because 0 is an invalid value for it.
self.repetition_penalty.np.fill(1.0)
self.repetition_penalty.copy_to_uva()
# Statistics for penalties.
self.prompt_bin_mask = torch.zeros(
max_num_reqs,
cdiv(self.vocab_size, 32),
dtype=torch.int32,
device=self.device,
)
# TODO(woosuk): This tensor is rarely used but can be very large, taking up
# GBs of GPU memory. Optimize the memory usage.
self.output_bin_counts = torch.zeros(
max_num_reqs, self.vocab_size, dtype=torch.int32, device=self.device
)
self._new_penalties_reqs: list[int] = []
def add_request(self, req_idx: int, sampling_params: SamplingParams) -> None:
self.repetition_penalty.np[req_idx] = sampling_params.repetition_penalty
self.frequency_penalty.np[req_idx] = sampling_params.frequency_penalty
self.presence_penalty.np[req_idx] = sampling_params.presence_penalty
do_penalty = use_penalty(sampling_params)
self.use_penalty[req_idx] = do_penalty
if do_penalty:
self._new_penalties_reqs.append(req_idx)
def apply_staged_writes(self) -> None:
if self._new_penalties_reqs:
idx_mapping = async_tensor_h2d(
self._new_penalties_reqs,
dtype=torch.int32,
target_device=self.device,
pin_memory=True,
)
prefill_lens = self.req_states.prefill_len.np[self._new_penalties_reqs]
max_prefill_len = int(prefill_lens.max())
bincount(
idx_mapping,
self.req_states.all_token_ids.gpu,
self.req_states.prompt_len.gpu,
self.req_states.prefill_len.gpu,
self.prompt_bin_mask,
self.output_bin_counts,
max_prefill_len,
)
self._new_penalties_reqs.clear()
self.repetition_penalty.copy_to_uva()
self.frequency_penalty.copy_to_uva()
self.presence_penalty.copy_to_uva()
def apply_penalties(
self,
logits: torch.Tensor,
idx_mapping: torch.Tensor,
idx_mapping_np: np.ndarray,
input_ids: torch.Tensor,
expanded_local_pos: torch.Tensor,
num_speculative_tokens: int,
) -> None:
if not np.any(self.use_penalty[idx_mapping_np]):
# No request uses penalties. Skip the kernel launch.
return
apply_penalties(
logits,
idx_mapping,
input_ids,
expanded_local_pos,
self.repetition_penalty.gpu,
self.frequency_penalty.gpu,
self.presence_penalty.gpu,
self.prompt_bin_mask,
self.output_bin_counts,
num_speculative_tokens,
)
@triton.jit
def _penalties_kernel(
logits_ptr,
logits_stride,
idx_mapping_ptr,
token_ids_ptr,
expanded_local_pos_ptr,
repetition_penalty_ptr,
frequency_penalty_ptr,
presence_penalty_ptr,
prompt_bin_mask_ptr,
prompt_bin_mask_stride,
output_bin_counts_ptr,
output_bin_counts_stride,
vocab_size,
BLOCK_SIZE: tl.constexpr,
MAX_SPEC_LEN: tl.constexpr,
):
token_idx = tl.program_id(0)
req_state_idx = tl.load(idx_mapping_ptr + token_idx)
rep_penalty = tl.load(repetition_penalty_ptr + req_state_idx)
freq_penalty = tl.load(frequency_penalty_ptr + req_state_idx)
pres_penalty = tl.load(presence_penalty_ptr + req_state_idx)
use_rep_penalty = rep_penalty != 1.0
use_freq_penalty = freq_penalty != 0.0
use_pres_penalty = pres_penalty != 0.0
use_penalty = use_rep_penalty or use_freq_penalty or use_pres_penalty
if not use_penalty:
# Early return to avoid loading logits.
return
block_idx = tl.program_id(1)
block = block_idx * BLOCK_SIZE + tl.arange(0, BLOCK_SIZE)
mask = block < vocab_size
logits = tl.load(logits_ptr + token_idx * logits_stride + block, mask=mask)
logits = logits.to(tl.float32)
base_output_counts = tl.load(
output_bin_counts_ptr + req_state_idx * output_bin_counts_stride + block,
mask=mask,
other=0,
)
# Compute cumulative draft_counts from previous positions in this request
pos = tl.load(expanded_local_pos_ptr + token_idx)
start_idx = token_idx - pos
draft_counts = tl.zeros((BLOCK_SIZE,), dtype=tl.int32)
for prev_pos in tl.static_range(MAX_SPEC_LEN):
if prev_pos < pos:
prev_token = tl.load(token_ids_ptr + start_idx + prev_pos + 1)
token_match = block == prev_token
draft_counts = draft_counts + token_match.to(tl.int32)
# Total counts = base output counts + cumulative draft counts
output_bin_counts = base_output_counts + draft_counts
output_bin_mask = output_bin_counts > 0
# Apply repetition penalties.
if use_rep_penalty:
packed_block = block_idx * BLOCK_SIZE // 32 + tl.arange(0, BLOCK_SIZE // 32)
packed_mask = tl.load(
prompt_bin_mask_ptr + req_state_idx * prompt_bin_mask_stride + packed_block,
mask=packed_block < tl.cdiv(vocab_size, 32),
other=0,
)
prompt_bin_mask = (packed_mask[:, None] >> (tl.arange(0, 32)[None, :])) & 1
prompt_bin_mask = prompt_bin_mask.to(tl.int1)
prompt_bin_mask = prompt_bin_mask.reshape(BLOCK_SIZE)
# If token appears in prompt or output, apply, otherwise use 1.0 for no-op.
scale = tl.where(prompt_bin_mask | output_bin_mask, rep_penalty, 1.0)
# If logits are positive, divide by penalty, otherwise multiply by penalty.
logits *= tl.where(logits > 0, 1.0 / scale, scale)
# Apply frequency penalties.
logits -= freq_penalty * output_bin_counts
# Apply presence penalties.
logits -= pres_penalty * output_bin_mask
# Store back to logits.
tl.store(logits_ptr + token_idx * logits_stride + block, logits, mask=mask)
def apply_penalties(
logits: torch.Tensor,
idx_mapping: torch.Tensor,
token_ids: torch.Tensor,
expanded_local_pos: torch.Tensor,
repetition_penalty: torch.Tensor,
frequency_penalty: torch.Tensor,
presence_penalty: torch.Tensor,
prompt_bin_mask: torch.Tensor,
output_bin_counts: torch.Tensor,
num_speculative_tokens: int,
) -> None:
num_tokens, vocab_size = logits.shape
BLOCK_SIZE = 8192
num_blocks = triton.cdiv(vocab_size, BLOCK_SIZE)
_penalties_kernel[(num_tokens, num_blocks)](
logits,
logits.stride(0),
idx_mapping,
token_ids,
expanded_local_pos,
repetition_penalty,
frequency_penalty,
presence_penalty,
prompt_bin_mask,
prompt_bin_mask.stride(0),
output_bin_counts,
output_bin_counts.stride(0),
vocab_size,
BLOCK_SIZE=BLOCK_SIZE,
MAX_SPEC_LEN=num_speculative_tokens,
)
@triton.jit
def _bincount_kernel(
idx_mapping_ptr,
all_token_ids_ptr,
all_token_ids_stride,
prompt_len_ptr,
prefill_len_ptr,
prompt_bin_mask_ptr,
prompt_bin_mask_stride,
output_bin_counts_ptr,
output_bin_counts_stride,
BLOCK_SIZE: tl.constexpr,
):
batch_idx = tl.program_id(0)
block_idx = tl.program_id(1)
req_state_idx = tl.load(idx_mapping_ptr + batch_idx)
prefill_len = tl.load(prefill_len_ptr + req_state_idx)
if block_idx * BLOCK_SIZE >= prefill_len:
return
prompt_len = tl.load(prompt_len_ptr + req_state_idx)
block = block_idx * BLOCK_SIZE + tl.arange(0, BLOCK_SIZE)
if block_idx * BLOCK_SIZE < prompt_len:
mask = block < prompt_len
prompt_tokens = tl.load(
all_token_ids_ptr + req_state_idx * all_token_ids_stride + block, mask=mask
)
idx = prompt_tokens // 32
bit_idx = prompt_tokens % 32
bit = tl.full((BLOCK_SIZE,), 1, tl.int32) << bit_idx
tl.atomic_or(
prompt_bin_mask_ptr + req_state_idx * prompt_bin_mask_stride + idx,
bit,
mask=mask,
)
if (block_idx + 1) * BLOCK_SIZE >= prompt_len:
mask = block < prefill_len
mask &= block >= prompt_len
output_tokens = tl.load(
all_token_ids_ptr + req_state_idx * all_token_ids_stride + block, mask=mask
)
tl.atomic_add(
output_bin_counts_ptr
+ req_state_idx * output_bin_counts_stride
+ output_tokens,
1,
mask=mask,
)
def bincount(
idx_mapping: torch.Tensor,
all_token_ids: torch.Tensor,
prompt_len: torch.Tensor,
prefill_len: torch.Tensor,
prompt_bin_mask: torch.Tensor,
output_bin_counts: torch.Tensor,
max_prefill_len: int,
) -> None:
prompt_bin_mask[idx_mapping] = 0
output_bin_counts[idx_mapping] = 0
num_reqs = idx_mapping.shape[0]
BLOCK_SIZE = 1024
num_blocks = triton.cdiv(max_prefill_len, BLOCK_SIZE)
_bincount_kernel[(num_reqs, num_blocks)](
idx_mapping,
all_token_ids,
all_token_ids.stride(0),
prompt_len,
prefill_len,
prompt_bin_mask,
prompt_bin_mask.stride(0),
output_bin_counts,
output_bin_counts.stride(0),
BLOCK_SIZE=BLOCK_SIZE,
)
def use_penalty(sampling_params: SamplingParams) -> bool:
return (
sampling_params.repetition_penalty != 1.0
or sampling_params.frequency_penalty != 0.0
or sampling_params.presence_penalty != 0.0
)