blob: 386ff640ca81b6d3aeb096ca1a491931cf34f23e [file] [log] [blame]
QEMU accel module:
This module provides utilities for discover and check the availability of
# Copyright (C) 2015-2016 Red Hat Inc.
# Copyright (C) 2012 IBM Corp.
# Authors:
# Fam Zheng <>
# This work is licensed under the terms of the GNU GPL, version 2. See
# the COPYING file in the top-level directory.
import logging
import os
import subprocess
from typing import List, Optional
LOG = logging.getLogger(__name__)
# Mapping host architecture to any additional architectures it can
# support which often includes its 32 bit cousin.
"x86_64": "i386",
"aarch64": "armhf",
"ppc64le": "ppc64",
def list_accel(qemu_bin: str) -> List[str]:
List accelerators enabled in the QEMU binary.
@param qemu_bin (str): path to the QEMU binary.
@raise Exception: if failed to run ``qemu -accel help``
@return a list of accelerator names.
if not qemu_bin:
return []
out = subprocess.check_output([qemu_bin, '-accel', 'help'],
LOG.debug("Failed to get the list of accelerators in %s", qemu_bin)
# Skip the first line which is the header.
return [acc.strip() for acc in out.splitlines()[1:]]
def kvm_available(target_arch: Optional[str] = None,
qemu_bin: Optional[str] = None) -> bool:
Check if KVM is available using the following heuristic:
- Kernel module is present in the host;
- Target and host arches don't mismatch;
- KVM is enabled in the QEMU binary.
@param target_arch (str): target architecture
@param qemu_bin (str): path to the QEMU binary
@return True if kvm is available, otherwise False.
if not os.access("/dev/kvm", os.R_OK | os.W_OK):
return False
if target_arch:
host_arch = os.uname()[4]
if target_arch != host_arch:
if target_arch != ADDITIONAL_ARCHES.get(host_arch):
return False
if qemu_bin and "kvm" not in list_accel(qemu_bin):
return False
return True
def tcg_available(qemu_bin: str) -> bool:
Check if TCG is available.
@param qemu_bin (str): path to the QEMU binary
return 'tcg' in list_accel(qemu_bin)