[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [RFC 01/24] qemu.py: Introduce _create_console() method
From: |
Cleber Rosa |
Subject: |
Re: [Qemu-devel] [RFC 01/24] qemu.py: Introduce _create_console() method |
Date: |
Fri, 11 May 2018 11:37:58 -0400 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 |
On 04/20/2018 03:56 PM, Eduardo Habkost wrote:
> On Fri, Apr 20, 2018 at 03:19:28PM -0300, Eduardo Habkost wrote:
>> From: Amador Pahim <address@hidden>
>>
>> This patch adds the QEMUMachine._create_console() method, which
>> returns a list with the chardev console device arguments to be
>> used in the qemu command line.
>>
>> Signed-off-by: Amador Pahim <address@hidden>
>> [ehabkost: reword commit message]
>> Signed-off-by: Eduardo Habkost <address@hidden>
>> ---
>> scripts/qemu.py | 49 ++++++++++++++++++++++++++++++++++++++++++++-----
>> 1 file changed, 44 insertions(+), 5 deletions(-)
>>
>> diff --git a/scripts/qemu.py b/scripts/qemu.py
>> index 08a3e9af5a..9e9d502543 100644
>> --- a/scripts/qemu.py
>> +++ b/scripts/qemu.py
>> @@ -55,7 +55,7 @@ class QEMUMachine(object):
>>
>> def __init__(self, binary, args=None, wrapper=None, name=None,
>> test_dir="/var/tmp", monitor_address=None,
>> - socket_scm_helper=None):
>> + socket_scm_helper=None, arch=None):
>> '''
>> Initialize a QEMUMachine
>>
>> @@ -91,6 +91,10 @@ class QEMUMachine(object):
>> self._test_dir = test_dir
>> self._temp_dir = None
>> self._launched = False
>> + if arch is None:
>> + arch = binary.split('-')[-1]
>
> This is not good. We don't want a test case to break only
> because we renamed a QEMU binary (e.g. RHEL uses
> /usr/libexec/qemu-kvm, and I can imagine people using qemu.py to
> write test scripts for it).
>
>
Agreed. This is a simple but fragile way of getting the arch for a
binary. How about getting this from the QEMU binary itself using a
"query-target" QMP command? This would, for the sake of simplicity,
require a separate QEMU execution, though.
But an even more important usability issue is this "automagic" behavior.
While it may be useful for higher level APIs, such as
"avocado_qemu.Test", IMO it should be explicitly enabled, and current
behavior should be preserved. Only by doing something like
m = QEMUMachine("/path/to/binary", automatic_devices=True)
Devices based on the architecture (and machine type?) would be added by
default. Naming is hard, so suggestions for the option name are
appreciated.
>> + self._arch = arch
>> + self._console_address = None
>>
>> # just in case logging wasn't configured by the main script:
>> logging.basicConfig()
>> @@ -179,6 +183,39 @@ class QEMUMachine(object):
>> '-mon', 'chardev=mon,mode=control',
>> '-display', 'none', '-vga', 'none']
>>
>> + def _create_console(self, console_address):
>> + for item in self._args:
>> + for option in ['isa-serial', 'spapr-vty', 'sclpconsole']:
>> + if option in item:
>> + return []
>
> This is very fragile. What's the goal of this chunk of code?
>
>
Agreed again.
>> +
>> + chardev = 'socket,id=console,{address},server,nowait'
>> + if console_address is None:
>> + console_address = tempfile.mktemp()
>> + chardev = chardev.format(address='path=%s' %
>> + console_address)
>> + elif isinstance(console_address, tuple):
>> + chardev = chardev.format(address='host=%s,port=%s' %
>> + (console_address[0],
>> + console_address[1]))
>> + else:
>> + chardev = chardev.format(address='path=%s' % console_address)
>> +
>> + self._console_address = console_address
>> +
>> + device = '{dev_type},chardev=console'
>> + if '86' in self._arch:
>> + device = device.format(dev_type='isa-serial')
>> + elif 'ppc' in self._arch:
>> + device = device.format(dev_type='spapr-vty')
In my executions with both ppc and ppc64, it failed with ppc not
supporting spapr-vty. I'd go with exact arch matches, and not
approximations.
>> + elif 's390x' in self._arch:
>> + device = device.format(dev_type='sclpconsole')
And this is fragile because s390x won't allow for more than one operator
console. Exact qemu-system-s390x output is:
Multiple VT220 operator consoles are not supported
SCLP event initialization failed.
>
> Why do we need this? Why isn't -serial enough?
>
>
No, some arches need special handling, but this is indeed too fragile.
>> + else:
>> + return []
>> +
>> + return ['-chardev', chardev,
>> + '-device', device]
>> +
>> def _pre_launch(self):
>> self._temp_dir = tempfile.mkdtemp(dir=self._test_dir)
>> if self._monitor_address is not None:
>> @@ -206,7 +243,7 @@ class QEMUMachine(object):
>> shutil.rmtree(self._temp_dir)
>> self._temp_dir = None
>>
>> - def launch(self):
>> + def launch(self, console_address=None):
Querying the console address should be available to users, but I don't
see the reason for making it a launch() argument.
>> """
>> Launch the VM and make sure we cleanup and expose the
>> command line/output in case of exception
>> @@ -218,7 +255,7 @@ class QEMUMachine(object):
>> self._iolog = None
>> self._qemu_full_args = None
>> try:
>> - self._launch()
>> + self._launch(console_address)
>> self._launched = True
>> except:
>> self.shutdown()
>> @@ -230,12 +267,14 @@ class QEMUMachine(object):
>> LOG.debug('Output: %r', self._iolog)
>> raise
>>
>> - def _launch(self):
>> + def _launch(self, console_address):
>> '''Launch the VM and establish a QMP connection'''
>> devnull = open(os.path.devnull, 'rb')
>> self._pre_launch()
>> + bargs = self._base_args()
>> + bargs.extend(self._create_console(console_address))
>> self._qemu_full_args = (self._wrapper + [self._binary] +
>> - self._base_args() + self._args)
>> + bargs + self.args)
With the addition of "automagic" devices, I'd propose three internal
argument categories:
1) base args (self._base_args()), which will always be necessary and
created by QEMUMachine.
2) auto args, always empty if QEMUMachine() is not given
automatic_devices=True.
3) user args (self._args)
- Cleber.
>> self._popen = subprocess.Popen(self._qemu_full_args,
>> stdin=devnull,
>> stdout=self._qemu_log_file,
>> --
>> 2.14.3
>>
>
[Prev in Thread] |
Current Thread |
[Next in Thread] |
- Re: [Qemu-devel] [RFC 01/24] qemu.py: Introduce _create_console() method,
Cleber Rosa <=