blob: ab5e040acbd4d0e647dd99caa50ad7b99868f080 [file] [log] [blame]
# Copyright 2020 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
"""Workaround for qemu-img bug on arm64 platforms with multiple cores.
Runs qemu-img command with timeout and retries the command if it hangs.
See: QEMU is out of date; current version of qemu-img
is unstable qemu-img hangs on
rcu_call_ready_event logic in Aarch64 when converting images
TODO( Remove this workaround when the bug is fixed.
import logging
import subprocess
import tempfile
import time
# qemu-img p99 run time on Cavium ThunderX2 servers is 26 seconds.
# Using 2x the p99 time as the timeout.
def _ExecQemuImgWithTimeout(command):
"""Execute qemu-img command in subprocess with timeout.
Returns: None if command timed out or return code if command completed.
"""'qemu-img starting')
command_output_file = tempfile.NamedTemporaryFile('w')
p = subprocess.Popen(command, stdout=command_output_file,
start_sec = time.time()
while p.poll() is None and time.time() - start_sec < QEMU_IMG_TIMEOUT_SEC:
stop_sec = time.time()'qemu-img duration: %f' % float(stop_sec - start_sec))
if p.poll() is None:
returncode = None
returncode = p.returncode
log_level = logging.WARN if returncode else logging.DEBUG
for line in open(, 'r'):
logging.log(log_level, 'qemu-img stdout: ' + line.strip())
return returncode
def ExecQemuImgWithRetry(command):
""" Execute qemu-img command in subprocess with 2 retries.
Raises CalledProcessError if command does not complete successfully.
tries = 0
status = None
while status is None and tries <= 2:
tries += 1
status = _ExecQemuImgWithTimeout(command)
if status is None:
raise subprocess.CalledProcessError(-1, command)
if status:
raise subprocess.CalledProcessError(status, command)