Files
vllm-omni/tests/diffusion/distributed/test_a2a_permute.py
2026-08-31 12:04:58 +08:00

117 lines
4.4 KiB
Python

# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM-Omni project
from __future__ import annotations
from dataclasses import dataclass
from types import SimpleNamespace
import pytest
import torch
from vllm_omni.diffusion.distributed import a2a_permute
pytestmark = [pytest.mark.core_model, pytest.mark.cpu]
def test_jit_build_includes_cuda_headers_from_nvidia_wheels(tmp_path, monkeypatch) -> None:
cu13_include = tmp_path / "nvidia" / "cu13" / "include"
nccl_include = tmp_path / "nvidia" / "nccl" / "include"
nccl_lib = tmp_path / "nvidia" / "nccl" / "lib" / "libnccl.so.2"
cu13_include.mkdir(parents=True)
nccl_include.mkdir(parents=True)
nccl_lib.parent.mkdir(parents=True)
(cu13_include / "cusparse.h").touch()
(nccl_include / "nccl.h").touch()
nccl_lib.touch()
load_kwargs = {}
monkeypatch.setattr(a2a_permute.sysconfig, "get_paths", lambda: {"purelib": str(tmp_path)})
monkeypatch.setattr(
torch.utils.cpp_extension,
"load",
lambda **kwargs: load_kwargs.update(kwargs),
)
monkeypatch.setattr(a2a_permute.symm_mem, "set_backend", lambda _backend: None)
monkeypatch.setattr(a2a_permute, "_BUILT", False)
a2a_permute.ensure_a2a_permute_available()
assert set(load_kwargs["extra_include_paths"]) == {str(cu13_include), str(nccl_include)}
assert load_kwargs["extra_ldflags"] == [str(nccl_lib)]
@dataclass
class _FakeAllocation:
"""Byte workspace stand-in that slices and reinterprets like ``symm_mem.empty()``."""
size: int
device: torch.device
def __post_init__(self) -> None:
self.buffer = torch.empty(self.size, dtype=torch.uint8)
def __getitem__(self, item: slice) -> torch.Tensor:
return self.buffer[item]
def test_workspace_reuses_peak_capacity_across_shapes(monkeypatch) -> None:
allocations: list[_FakeAllocation] = []
all_reduce_calls: list[object] = []
synchronize_calls: list[torch.device] = []
stream_id = [1]
a2a_permute._SYMM_WORKSPACES.clear()
monkeypatch.setattr(a2a_permute.torch.cuda, "is_current_stream_capturing", lambda: False)
monkeypatch.setattr(
a2a_permute.torch.cuda,
"current_stream",
lambda _device: SimpleNamespace(cuda_stream=stream_id[0]),
)
monkeypatch.setattr(a2a_permute, "_resolve_process_group", lambda _name: object())
monkeypatch.setattr(a2a_permute.torch, "ones", lambda *_args, **_kwargs: object())
monkeypatch.setattr(
a2a_permute.dist,
"all_reduce",
lambda _tensor, group: all_reduce_calls.append(group),
)
monkeypatch.setattr(
a2a_permute.torch.accelerator,
"synchronize",
lambda device: synchronize_calls.append(device),
)
def empty(size, *, dtype, device):
assert dtype == torch.uint8
allocation = _FakeAllocation(size=size, device=torch.device(device))
allocations.append(allocation)
return allocation
monkeypatch.setattr(a2a_permute.symm_mem, "empty", empty)
# The handle is only retained to keep the rendezvous registration alive.
monkeypatch.setattr(a2a_permute.symm_mem, "rendezvous", lambda _allocation, _group: object())
device = torch.device("cuda:0")
first = a2a_permute._get_symm_buffer((2, 3), torch.float16, device, "group")
smaller = a2a_permute._get_symm_buffer((1, 4), torch.float16, device, "group")
larger = a2a_permute._get_symm_buffer((4, 3), torch.float16, device, "group")
assert (first.shape, first.dtype) == ((2, 3), torch.float16)
assert (smaller.shape, smaller.dtype) == ((1, 4), torch.float16)
assert (larger.shape, larger.dtype) == ((4, 3), torch.float16)
# A sub-capacity request reuses the workspace; only growth allocates again.
assert smaller.untyped_storage().data_ptr() == first.untyped_storage().data_ptr()
assert larger.untyped_storage().data_ptr() != first.untyped_storage().data_ptr()
assert [allocation.size for allocation in allocations] == [12, 24]
assert len(a2a_permute._SYMM_WORKSPACES) == 1
assert len(all_reduce_calls) == 1
assert synchronize_calls == [device, device]
stream_id[0] = 2
with pytest.raises(RuntimeError, match="single CUDA stream"):
a2a_permute._get_symm_buffer((1, 4), torch.float16, device, "group")
a2a_permute.clear_a2a_permute_workspaces()
assert not a2a_permute._SYMM_WORKSPACES
assert synchronize_calls == [device, device, device]