Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2020-12-18' into staging

Block patches:
- New block filter: preallocate (which, on writes beyond an image file's
  end, allocates big chunks of data so that such post-EOF writes will
  occur less frequently)
- write-zeroes and block-status support for Quorum
- Implementation of truncate for the nvme block driver similarly to the
  existing implementations for host block devices and iscsi devices
- Block layer refactoring: Drop the tighten_restrictions concept in the
  block permission functions
- iotest fixes

# gpg: Signature made Fri 18 Dec 2020 14:45:30 GMT
# gpg:                using RSA key 91BEB60A30DB3E8857D11829F407DB0061D5CF40
# gpg:                issuer "mreitz@redhat.com"
# gpg: Good signature from "Max Reitz <mreitz@redhat.com>" [full]
# Primary key fingerprint: 91BE B60A 30DB 3E88 57D1  1829 F407 DB00 61D5 CF40

* remotes/maxreitz/tags/pull-block-2020-12-18: (30 commits)
  iotests: Fix _send_qemu_cmd with bash 5.1
  iotests/102: Pass $QEMU_HANDLE to _send_qemu_cmd
  block/nvme: Implement fake truncate() coroutine
  quorum: Implement bdrv_co_pwrite_zeroes()
  quorum: Implement bdrv_co_block_status()
  scripts/simplebench: add bench_prealloc.py
  simplebench/results_to_text: make executable
  simplebench/results_to_text: add difference line to the table
  simplebench/results_to_text: improve view of the table
  simplebench: move results_to_text() into separate file
  simplebench: rename ascii() to results_to_text()
  scripts/simplebench: use standard deviation for +- error
  scripts/simplebench: support iops
  scripts/simplebench: fix grammar: s/successed/succeeded/
  iotests: add 298 to test new preallocate filter driver
  iotests.py: execute_setup_common(): add required_fmts argument
  iotests: qemu_io_silent: support --image-opts
  qemu-io: add preallocate mode parameter for truncate command
  block: introduce preallocate filter
  block: bdrv_check_perm(): process children anyway
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 132 insertions, 0 deletions

diff --git a/scripts/simplebench/bench_prealloc.py b/scripts/simplebench/bench_prealloc.py
new file mode 100755
index 0000000000..85f588c597
--- /dev/null
+++ b/scripts/simplebench/bench_prealloc.py
@@ -0,0 +1,132 @@
+#!/usr/bin/env python3
+#
+# Benchmark preallocate filter
+#
+# Copyright (c) 2020 Virtuozzo International GmbH.
+#
+# 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 sys
+import os
+import subprocess
+import re
+import json
+
+import simplebench
+from results_to_text import results_to_text
+
+
+def qemu_img_bench(args):
+    p = subprocess.run(args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT,
+                       universal_newlines=True)
+
+    if p.returncode == 0:
+        try:
+            m = re.search(r'Run completed in (\d+.\d+) seconds.', p.stdout)
+            return {'seconds': float(m.group(1))}
+        except Exception:
+            return {'error': f'failed to parse qemu-img output: {p.stdout}'}
+    else:
+        return {'error': f'qemu-img failed: {p.returncode}: {p.stdout}'}
+
+
+def bench_func(env, case):
+    fname = f"{case['dir']}/prealloc-test.qcow2"
+    try:
+        os.remove(fname)
+    except OSError:
+        pass
+
+    subprocess.run([env['qemu-img-binary'], 'create', '-f', 'qcow2', fname,
+                   '16G'], stdout=subprocess.DEVNULL,
+                   stderr=subprocess.DEVNULL, check=True)
+
+    args = [env['qemu-img-binary'], 'bench', '-c', str(case['count']),
+            '-d', '64', '-s', case['block-size'], '-t', 'none', '-n', '-w']
+    if env['prealloc']:
+        args += ['--image-opts',
+                 'driver=qcow2,file.driver=preallocate,file.file.driver=file,'
+                 f'file.file.filename={fname}']
+    else:
+        args += ['-f', 'qcow2', fname]
+
+    return qemu_img_bench(args)
+
+
+def auto_count_bench_func(env, case):
+    case['count'] = 100
+    while True:
+        res = bench_func(env, case)
+        if 'error' in res:
+            return res
+
+        if res['seconds'] >= 1:
+            break
+
+        case['count'] *= 10
+
+    if res['seconds'] < 5:
+        case['count'] = round(case['count'] * 5 / res['seconds'])
+        res = bench_func(env, case)
+        if 'error' in res:
+            return res
+
+    res['iops'] = case['count'] / res['seconds']
+    return res
+
+
+if __name__ == '__main__':
+    if len(sys.argv) < 2:
+        print(f'USAGE: {sys.argv[0]} <qemu-img binary> '
+              'DISK_NAME:DIR_PATH ...')
+        exit(1)
+
+    qemu_img = sys.argv[1]
+
+    envs = [
+        {
+            'id': 'no-prealloc',
+            'qemu-img-binary': qemu_img,
+            'prealloc': False
+        },
+        {
+            'id': 'prealloc',
+            'qemu-img-binary': qemu_img,
+            'prealloc': True
+        }
+    ]
+
+    aligned_cases = []
+    unaligned_cases = []
+
+    for disk in sys.argv[2:]:
+        name, path = disk.split(':')
+        aligned_cases.append({
+            'id': f'{name}, aligned sequential 16k',
+            'block-size': '16k',
+            'dir': path
+        })
+        unaligned_cases.append({
+            'id': f'{name}, unaligned sequential 64k',
+            'block-size': '16k',
+            'dir': path
+        })
+
+    result = simplebench.bench(auto_count_bench_func, envs,
+                               aligned_cases + unaligned_cases, count=5)
+    print(results_to_text(result))
+    with open('results.json', 'w') as f:
+        json.dump(result, f, indent=4)