Enable embedding lookup/lora_a logic for chunked backend (#17692)

Co-authored-by: Bruce Wu <mogicianwu@fb.com>
Co-authored-by: Baizhou Zhang <sobereddiezhang@gmail.com>
Co-authored-by: Ethan (Yusheng) Su <yushengsu.thu@gmail.com>
This commit is contained in:
Bruce Wu
2026-03-16 11:37:58 -07:00
committed by GitHub
parent 061ec582bf
commit 70a6fb53af
15 changed files with 930 additions and 46 deletions

View File

@@ -5,18 +5,28 @@ from typing import List, Optional, Tuple
import torch
from sglang.srt.layers.logits_processor import LogitsMetadata, LogitsProcessor
from sglang.srt.lora.backend.chunked_backend import ChunkedSgmvLoRABackend
from sglang.srt.lora.triton_ops import (
chunked_embedding_lora_a_forward,
chunked_sgmv_lora_expand_forward,
chunked_sgmv_lora_shrink_forward,
)
from sglang.srt.lora.triton_ops.chunked_sgmv_expand import _chunked_lora_expand_kernel
from sglang.srt.lora.triton_ops.chunked_sgmv_shrink import _chunked_lora_shrink_kernel
from sglang.srt.lora.utils import LoRABatchInfo
from sglang.test.lora_utils import reference_sgmv_expand, reference_sgmv_shrink
from sglang.srt.lora.utils import LoRABatchInfo, get_lm_head_pruned_lens
from sglang.srt.model_executor.forward_batch_info import ForwardMode
from sglang.test.ci.ci_register import register_cuda_ci
from sglang.test.lora_utils import (
reference_embedding_lora_a_shrink,
reference_sgmv_expand,
reference_sgmv_shrink,
)
CHUNK_SIZE = 16
register_cuda_ci(est_time=60, suite="nightly-1-gpu", nightly=True)
def reset_kernel_cache():
_chunked_lora_shrink_kernel._clear_cache()
@@ -100,6 +110,7 @@ class TestChunkedSGMV(unittest.TestCase):
self.dtype = torch.float16
self.input_dim = 2560 # Hidden dimension
self.max_seq_len = 1024
self.vocab_size = 32000 # Vocabulary size for embedding tests
# LoRA configurations: name -> (rank, output_q, output_k, output_v)
self.lora_configs = {
@@ -285,6 +296,42 @@ class TestChunkedSGMV(unittest.TestCase):
return stacked
def create_embedding_lora_a_weights(self, lora_ranks: torch.Tensor) -> torch.Tensor:
"""Create LoRA A weights for embedding lookup.
Args:
lora_ranks: Tensor of ranks for each LoRA adapter
Returns:
Tensor of shape (num_loras, max_rank, vocab_size)
"""
lora_ranks_cpu = lora_ranks.cpu().numpy()
num_loras = len(lora_ranks_cpu)
max_rank = int(lora_ranks_cpu.max()) if num_loras > 0 else 0
if max_rank == 0:
return torch.empty(
num_loras, 0, self.vocab_size, dtype=self.dtype, device=self.device
)
weights = torch.zeros(
num_loras, max_rank, self.vocab_size, dtype=self.dtype, device=self.device
)
for i, rank in enumerate(lora_ranks_cpu):
if rank > 0:
weights[i, :rank, :] = torch.randn(
rank, self.vocab_size, dtype=self.dtype, device=self.device
)
return weights
def create_test_input_ids(self, total_tokens: int) -> torch.Tensor:
"""Create random token IDs for embedding test."""
return torch.randint(
0, self.vocab_size, (total_tokens,), dtype=torch.int64, device=self.device
)
def create_test_batch(
self,
batch_composition: BatchComposition,
@@ -461,6 +508,36 @@ class TestChunkedSGMV(unittest.TestCase):
chunked_shrink, reference_shrink, rtol=self.RTOL, atol=self.ATOL
)
# Test chunked embedding LoRA A forward
# Create embedding-specific LoRA A weights with shape (num_loras, rank, vocab_size)
embedding_lora_a = self.create_embedding_lora_a_weights(
batch_info.lora_ranks
)
# Create input_ids (token indices) instead of hidden states
total_tokens = x.shape[0]
input_ids = self.create_test_input_ids(total_tokens)
chunked_shrink_embeddings = chunked_embedding_lora_a_forward(
input_ids, embedding_lora_a, batch_info, self.vocab_size
)
reference_shrink_embeddings = reference_embedding_lora_a_shrink(
input_ids,
embedding_lora_a,
lora_assignments_tensor,
seq_lengths_tensor,
lora_ranks_tensor,
self.vocab_size,
)
torch.testing.assert_close(
chunked_shrink_embeddings,
reference_shrink_embeddings,
rtol=self.RTOL,
atol=self.ATOL,
msg=f"Shrink test embedding loRA A operation failed for batch_size={batch_size}",
)
def test_expand_basic(self):
"""Test basic expand operation against PyTorch reference"""
for batch_size in [1, 2, 16, 64]:
@@ -644,5 +721,104 @@ class TestChunkedSGMV(unittest.TestCase):
)
class TestLmHeadPruningConsistency(unittest.TestCase):
"""Verify get_lm_head_pruned_lens (LoRA) stays consistent with
LogitsProcessor._get_pruned_states (logits_processor).
If this test fails, it likely means one side was changed without
updating the other. See cross-references in both functions.
"""
def _make_mock_forward_batch(
self,
forward_mode,
extend_seq_lens_cpu,
return_logprob=False,
logprob_start_lens_cpu=None,
):
class MockForwardBatch:
pass
batch = MockForwardBatch()
batch.forward_mode = forward_mode
batch.batch_size = len(extend_seq_lens_cpu)
batch.return_logprob = return_logprob
batch.extend_seq_lens_cpu = extend_seq_lens_cpu
batch.extend_logprob_start_lens_cpu = logprob_start_lens_cpu
return batch
def _count_pruned_states_tokens(
self,
forward_mode,
extend_seq_lens_cpu,
return_logprob=False,
logprob_start_lens_cpu=None,
):
"""Call _get_pruned_states and return the number of output tokens."""
total_tokens = sum(extend_seq_lens_cpu)
hidden_states = torch.zeros(total_tokens, 4)
logits_meta = LogitsMetadata(
forward_mode=forward_mode,
extend_return_logprob=return_logprob,
extend_seq_lens=torch.tensor(extend_seq_lens_cpu, dtype=torch.int64),
extend_seq_lens_cpu=extend_seq_lens_cpu,
extend_logprob_start_lens_cpu=logprob_start_lens_cpu,
)
# _get_pruned_states does not use self, so pass None
result = LogitsProcessor._get_pruned_states(
None, hidden_states, None, None, logits_meta
)
pruned_states = result[0]
return pruned_states.shape[0]
def _assert_consistency(
self,
forward_mode,
extend_seq_lens_cpu,
return_logprob=False,
logprob_start_lens_cpu=None,
):
mock_batch = self._make_mock_forward_batch(
forward_mode,
extend_seq_lens_cpu,
return_logprob,
logprob_start_lens_cpu,
)
pruned_lens = get_lm_head_pruned_lens(mock_batch)
actual_count = self._count_pruned_states_tokens(
forward_mode,
extend_seq_lens_cpu,
return_logprob,
logprob_start_lens_cpu,
)
if pruned_lens is None:
expected_count = sum(extend_seq_lens_cpu)
else:
expected_count = sum(pruned_lens)
self.assertEqual(
expected_count,
actual_count,
f"get_lm_head_pruned_lens expects {expected_count} tokens, "
f"but _get_pruned_states produces {actual_count}. "
f"These functions must stay in sync — see their cross-reference comments.",
)
def test_extend_no_logprob(self):
self._assert_consistency(ForwardMode.EXTEND, [4, 5, 6])
def test_extend_with_logprob(self):
self._assert_consistency(
ForwardMode.EXTEND,
[4, 5, 6],
return_logprob=True,
logprob_start_lens_cpu=[0, 5, 3],
)
if __name__ == "__main__":
unittest.main()

View File

@@ -28,6 +28,7 @@ Usage:
"""
import multiprocessing as mp
import os
import unittest
from typing import Any, Dict, List, Optional, Tuple
@@ -47,10 +48,13 @@ register_amd_ci(
suite="stage-b-test-small-1-gpu-amd",
)
# Test configuration constants
LORA_BACKEND = "triton"
BASE_MODEL = "meta-llama/Llama-2-7b-hf"
LORA_PATHS = ["yushengsu/sglang_lora_logprob_diff_without_tuning"]
LORA_BACKEND = "csgmv"
DISABLE_CUDA_GRAPH = False
LORA_TARGET_MODULES = None
LOGPROB_THRESHOLD = 1e-01
MAX_NEW_TOKENS = 32
# Default test prompts
DEFAULT_TEST_PROMPTS = [
@@ -442,7 +446,7 @@ class TestLoRAHFSGLLogprobDifference(CustomTestCase):
model_path: str,
lora_paths: List[str],
prompts: List[str],
max_new_tokens: int = 32,
max_new_tokens: int = MAX_NEW_TOKENS,
torch_dtype: torch.dtype = torch.float16,
lora_backend: str = LORA_BACKEND,
port: int = DEFAULT_PORT_FOR_SRT_TEST_RUNNER,
@@ -506,32 +510,51 @@ class TestLoRAHFSGLLogprobDifference(CustomTestCase):
"""
Basic test comparing HF and SGLang LoRA logprobs with small model.
"""
model_path = "meta-llama/Llama-2-7b-hf"
lora_paths = ["yushengsu/sglang_lora_logprob_diff_without_tuning"]
prompts = DEFAULT_TEST_PROMPTS[:2] # Use fewer prompts for faster testing
self._run_comparison_test(
model_path=model_path,
lora_paths=lora_paths,
model_path=BASE_MODEL,
lora_paths=LORA_PATHS,
prompts=prompts,
max_new_tokens=32,
)
def test_lora_logprob_comparison_full(self):
"""
Full test comparing HF and SGLang LoRA logprobs with all prompts.
"""
model_path = "meta-llama/Llama-2-7b-hf"
lora_paths = ["yushengsu/sglang_lora_logprob_diff_without_tuning"]
prompts = DEFAULT_TEST_PROMPTS
self._run_comparison_test(
model_path=model_path,
lora_paths=lora_paths,
prompts=prompts,
max_new_tokens=32,
model_path=BASE_MODEL,
lora_paths=LORA_PATHS,
prompts=DEFAULT_TEST_PROMPTS,
)
def test_lora_logprob_comparison_chunked(self):
"""
Test with logprobs chunking enabled and a small chunk size so that
even short prompts trigger the multi-pass lm_head LoRA path.
"""
saved = {}
env_overrides = {
"SGLANG_ENABLE_LOGITS_PROCESSER_CHUNK": "true",
"SGLANG_LOGITS_PROCESSER_CHUNK_SIZE": "4",
}
for key, val in env_overrides.items():
saved[key] = os.environ.get(key)
os.environ[key] = val
try:
self._run_comparison_test(
model_path=BASE_MODEL,
lora_paths=LORA_PATHS,
prompts=DEFAULT_TEST_PROMPTS,
)
finally:
for key, orig in saved.items():
if orig is None:
os.environ.pop(key, None)
else:
os.environ[key] = orig
if __name__ == "__main__":
try: