Re: [Qemu-devel] [PATCH v3 12/16] qemu-iotests: add mirroring test case

[Kevin Wolf]

Am 20.10.2012 15:47, schrieb Paolo Bonzini:
> Il 19/10/2012 18:19, Kevin Wolf ha scritto:
>> Am 18.10.2012 16:49, schrieb Paolo Bonzini:
>>> Signed-off-by: Paolo Bonzini <address@hidden>
>>> ---
>>>         v2->v3: new testcases test_cancel_after_ready and
>>>         test_medium_not_found, removed obsolete workaround
>>>         for os.remove failure.  Fixed copyright header.
>>>
>>>  tests/qemu-iotests/041     | 364 
>>> +++++++++++++++++++++++++++++++++++++++++++++
>>>  tests/qemu-iotests/041.out |   5 +
>>>  tests/qemu-iotests/group   |   1 +
>>>  3 file modificati, 370 inserzioni(+)
>>>  create mode 100755 tests/qemu-iotests/041
>>>  create mode 100644 tests/qemu-iotests/041.out
>>>
>>> diff --git a/tests/qemu-iotests/041 b/tests/qemu-iotests/041
>>> new file mode 100755
>>> index 0000000..ce99b00
>>> --- /dev/null
>>> +++ b/tests/qemu-iotests/041
>>> @@ -0,0 +1,364 @@
>>> +#!/usr/bin/env python
>>> +#
>>> +# Tests for image mirroring.
>>> +#
>>> +# Copyright (C) 2012 Red Hat, Inc.
>>> +#
>>> +# This program is free software; you can redistribute it and/or modify
>>> +# it under the terms of the GNU General Public License as published by
>>> +# the Free Software Foundation; either version 2 of the License, or
>>> +# (at your option) any later version.
>>> +#
>>> +# This program is distributed in the hope that it will be useful,
>>> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
>>> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
>>> +# GNU General Public License for more details.
>>> +#
>>> +# You should have received a copy of the GNU General Public License
>>> +# along with this program.  If not, see <http://www.gnu.org/licenses/>.
>>> +#
>>> +
>>> +import time
>>> +import os
>>> +import iotests
>>> +from iotests import qemu_img, qemu_io
>>> +import struct
>>> +
>>> +backing_img = os.path.join(iotests.test_dir, 'backing.img')
>>> +target_backing_img = os.path.join(iotests.test_dir, 'target-backing.img')
>>> +test_img = os.path.join(iotests.test_dir, 'test.img')
>>> +target_img = os.path.join(iotests.test_dir, 'target.img')
>>> +
>>> +class ImageMirroringTestCase(iotests.QMPTestCase):
>>> +    '''Abstract base class for image mirroring test cases'''
>>> +
>>> +    def assert_no_active_mirrors(self):
>>> +        result = self.vm.qmp('query-block-jobs')
>>> +        self.assert_qmp(result, 'return', [])
>>> +
>>> +    def cancel_and_wait(self, drive='drive0', wait_ready=True):
>>> +        '''Cancel a block job and wait for it to finish'''
>>> +        if wait_ready:
>>> +            ready = False
>>> +            while not ready:
>>> +                for event in self.vm.get_qmp_events(wait=True):
>>> +                    if event['event'] == 'BLOCK_JOB_READY':
>>> +                        self.assert_qmp(event, 'data/type', 'mirror')
>>> +                        self.assert_qmp(event, 'data/device', drive)
>>> +                        ready = True
>>> +
>>> +        result = self.vm.qmp('block-job-cancel', device=drive,
>>> +                             force=not wait_ready)
>>> +        self.assert_qmp(result, 'return', {})
>>> +
>>> +        cancelled = False
>>> +        while not cancelled:
>>> +            for event in self.vm.get_qmp_events(wait=True):
>>> +                if event['event'] == 'BLOCK_JOB_COMPLETED' or \
>>> +                   event['event'] == 'BLOCK_JOB_CANCELLED':
>>> +                    self.assert_qmp(event, 'data/type', 'mirror')
>>> +                    self.assert_qmp(event, 'data/device', drive)
>>> +                    if wait_ready:
>>> +                        self.assertEquals(event['event'], 
>>> 'BLOCK_JOB_COMPLETED')
>>> +                        self.assert_qmp(event, 'data/offset', 
>>> self.image_len)
>>> +                        self.assert_qmp(event, 'data/len', self.image_len)
>>> +                    cancelled = True
>>> +
>>> +        self.assert_no_active_mirrors()
>>> +
>>> +    def complete_and_wait(self, drive='drive0', wait_ready=True):
>>> +        '''Complete a block job and wait for it to finish'''
>>> +        if wait_ready:
>>> +            ready = False
>>> +            while not ready:
>>> +                for event in self.vm.get_qmp_events(wait=True):
>>> +                    if event['event'] == 'BLOCK_JOB_READY':
>>> +                        self.assert_qmp(event, 'data/type', 'mirror')
>>> +                        self.assert_qmp(event, 'data/device', drive)
>>> +                        ready = True
>>> +
>>> +        result = self.vm.qmp('block-job-complete', device=drive)
>>> +        self.assert_qmp(result, 'return', {})
>>> +
>>> +        completed = False
>>> +        while not completed:
>>> +            for event in self.vm.get_qmp_events(wait=True):
>>> +                if event['event'] == 'BLOCK_JOB_COMPLETED':
>>> +                    self.assert_qmp(event, 'data/type', 'mirror')
>>> +                    self.assert_qmp(event, 'data/device', drive)
>>> +                    self.assert_qmp_absent(event, 'data/error')
>>> +                    self.assert_qmp(event, 'data/offset', self.image_len)
>>> +                    self.assert_qmp(event, 'data/len', self.image_len)
>>> +                    completed = True
>>> +
>>> +        self.assert_no_active_mirrors()
>>> +
>>> +    def create_image(self, name, size):
>>> +        file = open(name, 'w')
>>> +        i = 0
>>> +        while i < size:
>>> +            sector = struct.pack('>l504xl', i / 512, i / 512)
>>> +            file.write(sector)
>>> +            i = i + 512
>>> +        file.close()
>>> +
>>> +    def compare_images(self, img1, img2):
>>> +        try:
>>> +            qemu_img('convert', '-f', iotests.imgfmt, '-O', 'raw', img1, 
>>> img1 + '.raw')
>>> +            qemu_img('convert', '-f', iotests.imgfmt, '-O', 'raw', img2, 
>>> img2 + '.raw')
>>> +            file1 = open(img1 + '.raw', 'r')
>>> +            file2 = open(img2 + '.raw', 'r')
>>> +            return file1.read() == file2.read()
>>> +        finally:
>>> +            if file1 is not None:
>>> +                file1.close()
>>> +            if file2 is not None:
>>> +                file2.close()
>>> +            try:
>>> +                os.remove(img1 + '.raw')
>>> +            except OSError:
>>> +                pass
>>> +            try:
>>> +                os.remove(img2 + '.raw')
>>> +            except OSError:
>>> +                pass
>>> +
>>> +class TestSingleDrive(ImageMirroringTestCase):
>>> +    image_len = 1 * 1024 * 1024 # MB
>>> +
>>> +    def setUp(self):
>>> +        self.create_image(backing_img, TestSingleDrive.image_len)
>>> +        qemu_img('create', '-f', iotests.imgfmt, '-o', 'backing_file=%s' % 
>>> backing_img, test_img)
>>> +        self.vm = iotests.VM().add_drive(test_img)
>>> +        self.vm.launch()
>>> +
>>> +    def tearDown(self):
>>> +        self.vm.shutdown()
>>> +        os.remove(test_img)
>>> +        os.remove(backing_img)
>>> +        try:
>>> +            os.remove(target_img)
>>> +        except OSError:
>>> +            pass
>>> +
>>> +    def test_complete(self):
>>> +        self.assert_no_active_mirrors()
>>> +
>>> +        result = self.vm.qmp('drive-mirror', device='drive0', sync='full',
>>> +                             target=target_img)
>>> +        self.assert_qmp(result, 'return', {})
>>> +
>>> +        self.complete_and_wait()
>>> +        result = self.vm.qmp('query-block')
>>> +        self.assert_qmp(result, 'return[0]/inserted/file', target_img)
>>> +        self.vm.shutdown()
>>> +        self.assertTrue(self.compare_images(test_img, target_img),
>>> +                        'target image does not match source after 
>>> mirroring')
>>> +
>>> +    def test_cancel(self):
>>> +        self.assert_no_active_mirrors()
>>> +
>>> +        result = self.vm.qmp('drive-mirror', device='drive0', sync='full',
>>> +                             target=target_img)
>>> +        self.assert_qmp(result, 'return', {})
>>> +
>>> +        self.cancel_and_wait(wait_ready=False)
>>> +        result = self.vm.qmp('query-block')
>>> +        self.assert_qmp(result, 'return[0]/inserted/file', test_img)
>>> +        self.vm.shutdown()
>>> +        self.assertTrue(self.compare_images(test_img, target_img),
>>> +                        'target image does not match source after 
>>> mirroring')
>>
>> Hm, shouldn't the image comparison actually fail when cancelling before
>> the job was ready?
> 
> It's racy, it is probably completing anyway.  Should I send a v4 with a
> regenerated .out and the assertion removed?

Yes, please.

Can we additionaly increase our chances to win the race, for example by
specifying a very low speed?

Kevin