This patch *doesn't* update all of the docstring standards across the QEMU package directory to make our docstring usage consistent. It *doesn't* fix the formatting to make it look pretty or reasonable in generated output. It *does* fix a few small instances where Sphinx would emit a build warning because of malformed ReST -- If we built our Python docs with Sphinx. Signed-off-by: John Snow <jsnow@redhat.com> Reviewed-by: Willian Rampazzo <willianr@redhat.com> Reviewed-by: Wainer dos Santos Moschetta <wainersm@redhat.com> Message-id: 20210629214323.1329806-16-jsnow@redhat.com Signed-off-by: John Snow <jsnow@redhat.com>
85 lines
2.3 KiB
Python
85 lines
2.3 KiB
Python
"""
|
|
QEMU accel module:
|
|
|
|
This module provides utilities for discover and check the availability of
|
|
accelerators.
|
|
"""
|
|
# Copyright (C) 2015-2016 Red Hat Inc.
|
|
# Copyright (C) 2012 IBM Corp.
|
|
#
|
|
# Authors:
|
|
# Fam Zheng <famz@redhat.com>
|
|
#
|
|
# 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.
|
|
ADDITIONAL_ARCHES = {
|
|
"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 []
|
|
try:
|
|
out = subprocess.check_output([qemu_bin, '-accel', 'help'],
|
|
universal_newlines=True)
|
|
except:
|
|
LOG.debug("Failed to get the list of accelerators in %s", qemu_bin)
|
|
raise
|
|
# 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)
|