This is an example script that can be used to help generate a config
file that will reproduce a given CPU model from QEMU. The generated
config file can be loaded using "-readconfig" to make QEMU create CPUs
that will look exactly like the one used when cpu-model-dump was run.
A cpu-model-dump-selftest script is also provided, to help ensure that
the output of cpu-model-dump will produce the same config when run under
cpu-model-dump again.
Signed-off-by: Eduardo Habkost <ehabk...@redhat.com>
---
Changes v1 -> v2:
* Use "cpuid-" prefix instead of "feat-"
* Exit earlier if QEMU fails
* Exit code of the script will match QEMU or diff exit code
---
scripts/x86-cpu-model-dump | 221 ++++++++++++++++++++++++++++++++++++
scripts/x86-cpu-model-dump-selftest | 41 +++++++
2 files changed, 262 insertions(+)
create mode 100755 scripts/x86-cpu-model-dump
create mode 100755 scripts/x86-cpu-model-dump-selftest
diff --git a/scripts/x86-cpu-model-dump b/scripts/x86-cpu-model-dump
new file mode 100755
index 0000000..38812ab
--- /dev/null
+++ b/scripts/x86-cpu-model-dump
@@ -0,0 +1,221 @@
+#!/usr/bin/env python2.7
+#
+# Script to dump CPU model information as a QEMU config file that can be loaded
+# using -readconfig
+#
+# Author: Eduardo Habkost <ehabk...@redhat.com>
+#
+# Copyright (c) 2015 Red Hat Inc.
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+
+import sys, os, signal, tempfile, re
+import xml.etree.ElementTree
+
+# Allow us to load the qmp/qmp.py module:
+sys.path.append(os.path.join(os.path.dirname(sys.argv[0]), 'qmp'))
+import qmp
+
+CPU_PATH = '/machine/icc-bridge/icc/child[0]'
+RE_PROPS =
re.compile('x?level2?|vendor|family|model|stepping|cpuid-.*|model-id')
+CPU_MAP = '/usr/share/libvirt/cpu_map.xml'
+
+# features that may not be on cpu_map.xml:
+KNOWN_FEAT_NAMES = [
+ (0x40000001,0,'eax', [
+ "kvmclock", "kvm-nopiodelay", "kvm-mmu", "kvmclock",
+ "kvm-asyncpf", "kvm-steal-time", "kvm-pv-eoi", "kvm-pv-unhalt",
+ None, None, None, None,
+ None, None, None, None,
+ None, None, None, None,
+ None, None, None, None,
+ "kvmclock-stable-bit", None, None, None,
+ None, None, None, None,
+ ]),
+ (0xd,1,'eax',[
+ "xsaveopt", "xsavec", "xgetbv1", "xsaves",
+ ]),
+ # CPU feature aliases don't have properties, add some special feature
+ # names telling the script to ignore them:
+ (0x80000001,0,'edx',[
+ "fpu-ALIAS", "vme-ALIAS", "de-ALIAS", "pse-ALIAS",
+ "tsc-ALIAS", "msr-ALIAS", "pae-ALIAS", "mce-ALIAS",
+ "cx8-ALIAS", "apic-ALIAS", None, None,
+ "mtrr-ALIAS", "pge-ALIAS", "mca-ALIAS", "cmov-ALIAS",
+ "pat-ALIAS", "pse36-ALIAS", None, None,
+ None, None, None, "mmx-ALIAS",
+ "fxsr-ALIAS", None, None, None,
+ None, None, None, None,
+ ])
+]
+
+def value_to_string(ptype, v):
+ """Convert property value to string parseable by -global"""
+ if ptype == "bool":
+ return v and "on" or "off"
+ elif ptype == 'string':
+ return v
+ elif ptype.startswith('int') or ptype.startswith('uint'):
+ return str(v)
+ else:
+ raise Exception("Unsupported property type: %s", ptype)
+
+def load_feat_names(cpu_map):
+ """Load feature names from libvirt cpu_map.xml"""
+ cpumap = xml.etree.ElementTree.parse(cpu_map)
+ feat_names = {}
+
+ for function,index,reg,names in KNOWN_FEAT_NAMES:
+ for bitnr,name in enumerate(names):
+ if name:
+ feat_names[(function,index,reg,bitnr)] = name
+
+ for f in cpumap.getroot().findall("./arch[@name='x86']/feature"):
+ fname = f.attrib['name']
+ for cpuid in f.findall('cpuid'):
+ function=int(cpuid.attrib['function'], 0)
+ index = 0
+ for reg in 'abcd':
+ regname = 'e%sx' % (reg)
+ if regname in cpuid.attrib:
+ v = int(cpuid.attrib[regname], 0)
+ for bitnr in range(32):
+ bitval = (1 << bitnr)
+ if v & bitval:
+ feat_names[(function,index,regname,bitnr)] = fname
+
+ return feat_names
+
+def dump_cpu_data(qmp, cpu_path):
+
+ feat_names = load_feat_names(CPU_MAP)
+
+ props = qmp.command('qom-list', path=cpu_path)
+ props = sorted([(prop['name'], prop['type']) for prop in props])
+
+ propdict = {}
+ for pname,ptype in props:
+ if RE_PROPS.match(pname):
+ value = qmp.command('qom-get', path=cpu_path, property=pname)
+ propdict[pname] = value_to_string(ptype, value)
+ #print >>sys.stderr, pname, propdict[pname]
+
+ # sanity-check feature-words and fix filtered-features:
+ for prop in ('feature-words', 'filtered-features'):
+ reply = qmp.command('qom-get', path=cpu_path, property=prop)
+ for fw in reply:
+ function = fw['cpuid-input-eax']
+ index = fw.get('cpuid-input-ecx', 0)
+ regname = fw['cpuid-register'].lower()
+ value = fw['features']
+ for bitnr in range(32):
+ bitval = (1 << bitnr)
+ is_set = (value & bitval) != 0
+ key = (function,index,regname,bitnr)
+ keystr = "0x%x,0x%x,%s,%d" % (function, index, regname, bitnr)
+ feat_name = feat_names.get(key)
+
+ if feat_name is None:
+ if is_set:
+ raise Exception("Unknown feature is set: %s" %
(keystr))
+ else:
+ continue
+
+ # special case for alias bits: ignore them
+ if feat_name.endswith('-ALIAS'):
+ continue
+
+ pname = 'cpuid-%s' % (feat_name.replace('_', '-'))
+ if not propdict.has_key(pname):
+ if is_set:
+ raise Exception("Enabled feature with no property: %s"
% pname)
+ else:
+ continue
+
+ # feature-word bits must match property:
+ if prop == 'feature-words':
+ propvalue = value_to_string('bool', is_set)
+ assert propdict[pname] == propvalue
+ # bits set on filtered-features needs property fixup:
+ elif prop == 'filtered-features' and is_set:
+ assert propdict[pname] == 'off'
+ propdict[pname] = 'on'
+
+ for pname in sorted(propdict.keys()):
+ pvalue = propdict[pname]
+ print '[global]'
+ print 'driver = "cpu"'
+ print 'property = "%s"' % (pname)
+ print 'value = "%s"' % (pvalue)
+ print ''
+
+def main(argv):
+ args = argv[1:]
+ if len(args) < 1:
+ print >>sys.stderr, "Usage: %s <qemu> [<arguments>...]" % (argv[0])
+ return 1
+
+ qemu = args.pop(0)
+
+ sockdir = tempfile.mkdtemp()
+ sockpath = os.path.join(sockdir, 'monitor.sock')
+ pidfile = os.path.join(sockdir, 'pidfile')
+
+ try:
+ qemu_cmd = [qemu]
+ qemu_cmd.extend(args)
+ qemu_cmd.append('-chardev')
+ qemu_cmd.append('socket,id=qmp0,path=%s,server,nowait' % (sockpath))
+ qemu_cmd.append('-qmp')
+ qemu_cmd.append('chardev:qmp0')
+ qemu_cmd.append('-daemonize')
+ qemu_cmd.append('-pidfile')
+ qemu_cmd.append(pidfile)
+
+ ret = os.spawnvp(os.P_WAIT, qemu, qemu_cmd)
+ if ret != 0:
+ print >>sys.stderr, "Failed to start QEMU"
+ return 1
+
+ srv = qmp.QEMUMonitorProtocol(sockpath)
+ srv.connect()
+
+ dump_cpu_data(srv, CPU_PATH)
+ finally:
+ try:
+ pid = int(open(pidfile, 'r').read())
+ #print >>sys.stderr, 'Killing QEMU, pid: %d' % (pid)
+ os.kill(pid, signal.SIGTERM)
+ os.waitpid(pid, 0)
+ except:
+ pass
+ try:
+ os.unlink(pidfile)
+ except:
+ pass
+ try:
+ os.unlink(sockpath)
+ except:
+ pass
+ os.rmdir(sockdir)
+
+
+if __name__ == '__main__':
+ sys.exit(main(sys.argv))
diff --git a/scripts/x86-cpu-model-dump-selftest
b/scripts/x86-cpu-model-dump-selftest
new file mode 100755
index 0000000..3c62bca
--- /dev/null
+++ b/scripts/x86-cpu-model-dump-selftest
@@ -0,0 +1,41 @@
+#!/bin/bash
+# self-test script for cpu-model-dump: check if the generated config file
+# will make the script generate a similar config file
+#
+# Author: Eduardo Habkost <ehabk...@redhat.com>
+#
+# Copyright (c) 2015 Red Hat Inc.
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+DUMP_SCRIPT="$(dirname $0)/x86-cpu-model-dump"
+
+QEMU="$1"
+shift
+
+dump1="$(mktemp)"
+dump2="$(mktemp)"
+
+"$DUMP_SCRIPT" "$QEMU" "$@" > "$dump1" && \
+ "$DUMP_SCRIPT" "$QEMU" -readconfig "$dump1" > "$dump2" && \
+ diff -u "$dump1" "$dump2"
+E="$?"
+
+rm -f "$dump1" "$dump2"
+exit "$E"
--
2.1.0
