Files
xc-llm-ascend/vllm_ascend/worker/v2/sample/sampler.py
Ronald f1ffb5fb19 [Feature] adapt to uva buffer and main2main (#6657)
### What this PR does / why we need it?
vllm model runner v2 use uva buffer to prepare input data, but npu
doesn't support uva yet, this pr implement a uvawrapper class to mimic
gpu's uva backend. what's more, this pr make some modifications to adapt
to the newer main branch.

### Does this PR introduce _any_ user-facing change?
no
### How was this patch tested?
- vLLM main:
13397841ab

---------

Signed-off-by: Ronald1995 <ronaldautomobile@163.com>
2026-02-12 10:36:31 +08:00

82 lines
3.1 KiB
Python

# Adapt from https://github.com/vllm-project/vllm/blob/main/vllm/v1/worker/gpu/sample/sampler.py.
# Copyright (c) 2025 Huawei Technologies Co., Ltd. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# This file is a part of the vllm-ascend project.
#
import numpy as np
import torch
from vllm.v1.sample.ops.topk_topp_sampler import apply_top_k_top_p
from vllm.v1.worker.gpu.sample.gumbel import apply_temperature
from vllm.v1.worker.gpu.sample.min_p import apply_min_p
from vllm.v1.worker.gpu.sample.sampler import Sampler
from vllm_ascend.worker.v2.sample.gumbel import gumbel_sample
class AscendSampler(Sampler):
def sample(
self,
logits: torch.Tensor,
idx_mapping: torch.Tensor,
idx_mapping_np: np.ndarray,
pos: torch.Tensor,
input_ids: torch.Tensor,
expanded_local_pos: torch.Tensor,
) -> tuple[torch.Tensor, torch.Tensor]:
"""Override sample method because we need to override triton operators
called in the method.
"""
# Copy logits to a new FP32 tensor.
logits = torch.empty_like(logits, dtype=torch.float32).copy_(logits)
# Apply logit bias (e.g., allowed_token_ids, min_tokens) in place.
self.logit_bias_state.apply_logit_bias(logits, idx_mapping, idx_mapping_np, pos)
# Apply penalties in place.
self.penalties_state.apply_penalties(
logits,
idx_mapping,
idx_mapping_np,
input_ids,
expanded_local_pos,
self.num_speculative_tokens,
)
# Apply temperature in place.
apply_temperature(logits, idx_mapping, self.sampling_states.temperature.gpu)
# Apply min_p in place if any request has a non-zero min_p.
do_min_p = self.sampling_states.do_min_p(idx_mapping_np)
if do_min_p:
apply_min_p(logits, idx_mapping, self.sampling_states.min_p.gpu)
# Apply top_k and/or top_p. This might return a new tensor.
do_top_k = self.sampling_states.do_top_k(idx_mapping_np)
top_k = self.sampling_states.top_k.gpu[idx_mapping] if do_top_k else None
do_top_p = self.sampling_states.do_top_p(idx_mapping_np)
top_p = self.sampling_states.top_p.gpu[idx_mapping] if do_top_p else None
if do_top_k or do_top_p:
logits = apply_top_k_top_p(logits, top_k, top_p)
# Sample the next token.
sampled = gumbel_sample(
logits,
idx_mapping,
self.sampling_states.temperature.gpu,
self.sampling_states.seeds.gpu,
pos,
apply_temperature=False,
)
return sampled, logits