diff mbox series

[PULL,6/6] iotests: add backup-discard-source

Message ID 20240429115157.2260885-7-vsementsov@yandex-team.ru
State New
Headers show
Series [PULL,1/6] blockcommit: Reopen base image as RO after abort | expand

Commit Message

Vladimir Sementsov-Ogievskiy April 29, 2024, 11:51 a.m. UTC
Add test for a new backup option: discard-source.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
Tested-by: Fiona Ebner <f.ebner@proxmox.com>
Message-Id: <20240313152822.626493-6-vsementsov@yandex-team.ru>
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
---
 .../qemu-iotests/tests/backup-discard-source  | 152 ++++++++++++++++++
 .../tests/backup-discard-source.out           |   5 +
 2 files changed, 157 insertions(+)
 create mode 100755 tests/qemu-iotests/tests/backup-discard-source
 create mode 100644 tests/qemu-iotests/tests/backup-discard-source.out

Comments

Richard Henderson April 29, 2024, 2:18 p.m. UTC | #1
On 4/29/24 04:51, Vladimir Sementsov-Ogievskiy wrote:
> Add test for a new backup option: discard-source.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
> Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
> Tested-by: Fiona Ebner <f.ebner@proxmox.com>
> Message-Id: <20240313152822.626493-6-vsementsov@yandex-team.ru>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
> ---
>   .../qemu-iotests/tests/backup-discard-source  | 152 ++++++++++++++++++
>   .../tests/backup-discard-source.out           |   5 +
>   2 files changed, 157 insertions(+)
>   create mode 100755 tests/qemu-iotests/tests/backup-discard-source
>   create mode 100644 tests/qemu-iotests/tests/backup-discard-source.out

This fails check-python-minreqs

   https://gitlab.com/qemu-project/qemu/-/jobs/6739551782

It appears to be a pylint issue.


r~
Vladimir Sementsov-Ogievskiy April 29, 2024, 6:39 p.m. UTC | #2
[Add John]

On 29.04.24 17:18, Richard Henderson wrote:
> On 4/29/24 04:51, Vladimir Sementsov-Ogievskiy wrote:
>> Add test for a new backup option: discard-source.
>>
>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
>> Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
>> Tested-by: Fiona Ebner <f.ebner@proxmox.com>
>> Message-Id: <20240313152822.626493-6-vsementsov@yandex-team.ru>
>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
>> ---
>>   .../qemu-iotests/tests/backup-discard-source  | 152 ++++++++++++++++++
>>   .../tests/backup-discard-source.out           |   5 +
>>   2 files changed, 157 insertions(+)
>>   create mode 100755 tests/qemu-iotests/tests/backup-discard-source
>>   create mode 100644 tests/qemu-iotests/tests/backup-discard-source.out
> 
> This fails check-python-minreqs
> 
>    https://gitlab.com/qemu-project/qemu/-/jobs/6739551782
> 
> It appears to be a pylint issue.
> 
> 

tests/export-incoming-iothread:1:0: R0801: Similar lines in 2 files
==tests.backup-discard-source:[52:61]
==tests.copy-before-write:[54:63]
             'file': {
                 'driver': iotests.imgfmt,
                 'file': {
                     'driver': 'file',
                     'filename': source_img,
                 }
             },
             'target': {
                 'driver': iotests.imgfmt, (duplicate-code)



Hmm. I don't think, that something should be changed in code. splitting out part of this json object to a function? That's a test for QMP command, and it's good that we see the command as is in one place. I can swap some lines or rename variables to hack the linter, but I'd prefer not doing so:)


For me that looks like a false-positive: yes it's a duplication, but it should better be duplication, than complicating raw json objects by reusing common parts.


What to do? As described in 22305c2a081b8b6 "python: Reduce strictness of pylint's duplicate-code check", this check could be either be disabled completely, or we can increase min-similarity-lines config value.

I'd just disable it completely. Any thoughts?
Kevin Wolf April 30, 2024, 9:13 a.m. UTC | #3
Am 29.04.2024 um 20:39 hat Vladimir Sementsov-Ogievskiy geschrieben:
> [Add John]
> 
> On 29.04.24 17:18, Richard Henderson wrote:
> > On 4/29/24 04:51, Vladimir Sementsov-Ogievskiy wrote:
> > > Add test for a new backup option: discard-source.
> > > 
> > > Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
> > > Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
> > > Tested-by: Fiona Ebner <f.ebner@proxmox.com>
> > > Message-Id: <20240313152822.626493-6-vsementsov@yandex-team.ru>
> > > Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
> > > ---
> > >   .../qemu-iotests/tests/backup-discard-source  | 152 ++++++++++++++++++
> > >   .../tests/backup-discard-source.out           |   5 +
> > >   2 files changed, 157 insertions(+)
> > >   create mode 100755 tests/qemu-iotests/tests/backup-discard-source
> > >   create mode 100644 tests/qemu-iotests/tests/backup-discard-source.out
> > 
> > This fails check-python-minreqs
> > 
> >    https://gitlab.com/qemu-project/qemu/-/jobs/6739551782
> > 
> > It appears to be a pylint issue.
> > 
> > 
> 
> tests/export-incoming-iothread:1:0: R0801: Similar lines in 2 files
> ==tests.backup-discard-source:[52:61]
> ==tests.copy-before-write:[54:63]
>             'file': {
>                 'driver': iotests.imgfmt,
>                 'file': {
>                     'driver': 'file',
>                     'filename': source_img,
>                 }
>             },
>             'target': {
>                 'driver': iotests.imgfmt, (duplicate-code)
> 
> 
> 
> Hmm. I don't think, that something should be changed in code.
> splitting out part of this json object to a function? That's a test
> for QMP command, and it's good that we see the command as is in one
> place. I can swap some lines or rename variables to hack the linter,
> but I'd prefer not doing so:)
> 
> 
> For me that looks like a false-positive: yes it's a duplication, but
> it should better be duplication, than complicating raw json objects by
> reusing common parts.
> 
> 
> What to do? As described in 22305c2a081b8b6 "python: Reduce strictness
> of pylint's duplicate-code check", this check could be either be
> disabled completely, or we can increase min-similarity-lines config
> value.
> 
> I'd just disable it completely. Any thoughts?

I think it would make sense to treat tests differently from real
production code. In tests/, some duplication is bound to happen and
trying to unify things across test cases (which would mean moving to
iotests.py) often doesn't make sense. On the other hand, in python/ we
would probably want to unify duplicated code.

Kevin
Vladimir Sementsov-Ogievskiy April 30, 2024, 9:22 a.m. UTC | #4
On 30.04.24 12:13, Kevin Wolf wrote:
> Am 29.04.2024 um 20:39 hat Vladimir Sementsov-Ogievskiy geschrieben:
>> [Add John]
>>
>> On 29.04.24 17:18, Richard Henderson wrote:
>>> On 4/29/24 04:51, Vladimir Sementsov-Ogievskiy wrote:
>>>> Add test for a new backup option: discard-source.
>>>>
>>>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
>>>> Reviewed-by: Fiona Ebner <f.ebner@proxmox.com>
>>>> Tested-by: Fiona Ebner <f.ebner@proxmox.com>
>>>> Message-Id: <20240313152822.626493-6-vsementsov@yandex-team.ru>
>>>> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
>>>> ---
>>>>    .../qemu-iotests/tests/backup-discard-source  | 152 ++++++++++++++++++
>>>>    .../tests/backup-discard-source.out           |   5 +
>>>>    2 files changed, 157 insertions(+)
>>>>    create mode 100755 tests/qemu-iotests/tests/backup-discard-source
>>>>    create mode 100644 tests/qemu-iotests/tests/backup-discard-source.out
>>>
>>> This fails check-python-minreqs
>>>
>>>     https://gitlab.com/qemu-project/qemu/-/jobs/6739551782
>>>
>>> It appears to be a pylint issue.
>>>
>>>
>>
>> tests/export-incoming-iothread:1:0: R0801: Similar lines in 2 files
>> ==tests.backup-discard-source:[52:61]
>> ==tests.copy-before-write:[54:63]
>>              'file': {
>>                  'driver': iotests.imgfmt,
>>                  'file': {
>>                      'driver': 'file',
>>                      'filename': source_img,
>>                  }
>>              },
>>              'target': {
>>                  'driver': iotests.imgfmt, (duplicate-code)
>>
>>
>>
>> Hmm. I don't think, that something should be changed in code.
>> splitting out part of this json object to a function? That's a test
>> for QMP command, and it's good that we see the command as is in one
>> place. I can swap some lines or rename variables to hack the linter,
>> but I'd prefer not doing so:)
>>
>>
>> For me that looks like a false-positive: yes it's a duplication, but
>> it should better be duplication, than complicating raw json objects by
>> reusing common parts.
>>
>>
>> What to do? As described in 22305c2a081b8b6 "python: Reduce strictness
>> of pylint's duplicate-code check", this check could be either be
>> disabled completely, or we can increase min-similarity-lines config
>> value.
>>
>> I'd just disable it completely. Any thoughts?
> 
> I think it would make sense to treat tests differently from real
> production code. In tests/, some duplication is bound to happen and
> trying to unify things across test cases (which would mean moving to
> iotests.py) often doesn't make sense. On the other hand, in python/ we
> would probably want to unify duplicated code.
> 

Agree. Happily, it turns out that tests already have separate tests/qemu-iotests/pylintrc file, so that's not a problem. Still I decided to anot disable the check completely, but just bump the limit, see "[PATCH] iotests/pylintrc: allow up to 10 similar lines"
diff mbox series

Patch

diff --git a/tests/qemu-iotests/tests/backup-discard-source b/tests/qemu-iotests/tests/backup-discard-source
new file mode 100755
index 0000000000..2391b12acd
--- /dev/null
+++ b/tests/qemu-iotests/tests/backup-discard-source
@@ -0,0 +1,152 @@ 
+#!/usr/bin/env python3
+#
+# Test backup discard-source parameter
+#
+# Copyright (c) Virtuozzo International GmbH.
+# Copyright (c) Yandex
+#
+# 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 os
+
+import iotests
+from iotests import qemu_img_create, qemu_img_map, qemu_io
+
+
+temp_img = os.path.join(iotests.test_dir, 'temp')
+source_img = os.path.join(iotests.test_dir, 'source')
+target_img = os.path.join(iotests.test_dir, 'target')
+size = '1M'
+
+
+def get_actual_size(vm, node_name):
+    nodes = vm.cmd('query-named-block-nodes', flat=True)
+    node = next(n for n in nodes if n['node-name'] == node_name)
+    return node['image']['actual-size']
+
+
+class TestBackup(iotests.QMPTestCase):
+    def setUp(self):
+        qemu_img_create('-f', iotests.imgfmt, source_img, size)
+        qemu_img_create('-f', iotests.imgfmt, temp_img, size)
+        qemu_img_create('-f', iotests.imgfmt, target_img, size)
+        qemu_io('-c', 'write 0 1M', source_img)
+
+        self.vm = iotests.VM()
+        self.vm.launch()
+
+        self.vm.cmd('blockdev-add', {
+            'node-name': 'cbw',
+            'driver': 'copy-before-write',
+            'file': {
+                'driver': iotests.imgfmt,
+                'file': {
+                    'driver': 'file',
+                    'filename': source_img,
+                }
+            },
+            'target': {
+                'driver': iotests.imgfmt,
+                'discard': 'unmap',
+                'node-name': 'temp',
+                'file': {
+                    'driver': 'file',
+                    'filename': temp_img
+                }
+            }
+        })
+
+        self.vm.cmd('blockdev-add', {
+            'node-name': 'access',
+            'discard': 'unmap',
+            'driver': 'snapshot-access',
+            'file': 'cbw'
+        })
+
+        self.vm.cmd('blockdev-add', {
+            'driver': iotests.imgfmt,
+            'node-name': 'target',
+            'file': {
+                'driver': 'file',
+                'filename': target_img
+            }
+        })
+
+        self.assertLess(get_actual_size(self.vm, 'temp'), 512 * 1024)
+
+    def tearDown(self):
+        # That should fail, because region is discarded
+        self.vm.hmp_qemu_io('access', 'read 0 1M')
+
+        self.vm.shutdown()
+
+        self.assertTrue('read failed: Permission denied' in self.vm.get_log())
+
+        # Final check that temp image is empty
+        mapping = qemu_img_map(temp_img)
+        self.assertEqual(len(mapping), 1)
+        self.assertEqual(mapping[0]['start'], 0)
+        self.assertEqual(mapping[0]['length'], 1024 * 1024)
+        self.assertEqual(mapping[0]['data'], False)
+
+        os.remove(temp_img)
+        os.remove(source_img)
+        os.remove(target_img)
+
+    def do_backup(self):
+        self.vm.cmd('blockdev-backup', device='access',
+                    sync='full', target='target',
+                    job_id='backup0',
+                    discard_source=True)
+
+        self.vm.event_wait(name='BLOCK_JOB_COMPLETED')
+
+    def test_discard_written(self):
+        """
+        1. Guest writes
+        2. copy-before-write operation, data is stored to temp
+        3. start backup(discard_source=True), check that data is
+           removed from temp
+        """
+        # Trigger copy-before-write operation
+        result = self.vm.hmp_qemu_io('cbw', 'write 0 1M')
+        self.assert_qmp(result, 'return', '')
+
+        # Check that data is written to temporary image
+        self.assertGreater(get_actual_size(self.vm, 'temp'), 1024 * 1024)
+
+        self.do_backup()
+
+    def test_discard_cbw(self):
+        """
+        1. do backup(discard_source=True), which should inform
+           copy-before-write that data is not needed anymore
+        2. Guest writes
+        3. Check that copy-before-write operation is not done
+        """
+        self.do_backup()
+
+        # Try trigger copy-before-write operation
+        result = self.vm.hmp_qemu_io('cbw', 'write 0 1M')
+        self.assert_qmp(result, 'return', '')
+
+        # Check that data is not written to temporary image, as region
+        # is discarded from copy-before-write process
+        self.assertLess(get_actual_size(self.vm, 'temp'), 512 * 1024)
+
+
+if __name__ == '__main__':
+    iotests.main(supported_fmts=['qcow2'],
+                 supported_protocols=['file'])
diff --git a/tests/qemu-iotests/tests/backup-discard-source.out b/tests/qemu-iotests/tests/backup-discard-source.out
new file mode 100644
index 0000000000..fbc63e62f8
--- /dev/null
+++ b/tests/qemu-iotests/tests/backup-discard-source.out
@@ -0,0 +1,5 @@ 
+..
+----------------------------------------------------------------------
+Ran 2 tests
+
+OK