This is in response to:
https://bugzilla.redhat.com/show_bug.cgi?id=629662
Explanation
qemu's virtio-net-pci driver allows setting the algorithm used for tx
packets to either "bh" or "timer". This is done by adding ",tx=bh" or
",tx=timer" to the "-device virtio-net-pci" commandline option.
'bh' stands for 'bottom half'; when this is set, packet tx is all done
in an iothread in the bottom half of the driver. (In libvirt, this
option is called the more descriptive "iothread".)
'timer' means that tx work is done in qemu, and if there is more tx
data than can be sent at the present time, a timer is set before qemu
moves on to do other things; when the timer fires, another attempt is
made to send more data. (libvirt retains the name "timer" for this
option.)
The resulting difference, according to the qemu developer who added
the option is:
bh makes tx more asynchronous and reduces latency, but potentially
causes more processor bandwidth contention since the cpu doing the
tx isn't necessarily the cpu where the guest generated the
packets.
Solution
This patch provides a libvirt domain xml knob to change the option on
the qemu commandline, by adding a new attribute "txmode" to the
<driver> element that can be placed inside any <interface> element in
a domain definition. It's use would be something like this:
<interface ...>
...
<model type='virtio'/>
<driver txmode='iothread'/>
...
</interface>
I chose to put this setting as an attribute to <driver> rather than as
a sub-element to <tune> because it is specific to the virtio-net
driver, not something that is generally usable by all network drivers.
(note that this is the same placement as the "driver name=..."
attribute used to choose kernel vs. userland backend for the
virtio-net driver.)
Actually adding the tx=xxx option to the qemu commandline is only done
if the version of qemu being used advertises it in the output of
qemu -device virtio-net-pci,?
If a particular txmode is requested in the XML, and the option isn't
listed in that help output, an UNSUPPORTED_CONFIG error is logged, and
the domain fails to start.
QEMUD_CMD_FLAG_PCI_MULTIBUS should be set in the function
qemuCapsExtractVersionInfo()
The flag QEMUD_CMD_FLAG_PCI_MULTIBUS is used in the function
qemuBuildDeviceAddressStr(). All callers get qemuCmdFlags
by the function qemuCapsExtractVersionInfo() except that
testCompareXMLToArgvFiles() in qemuxml2argvtest.c.
So we should set QEMUD_CMD_FLAG_PCI_MULTIBUS in the function
qemuCapsExtractVersionInfo() instead of qemuBuildCommandLine()
because the function qemuBuildCommandLine() does not be called
when we attach a pci device.
tests: set QEMUD_CMD_FLAG_PCI_MULTIBUS in testCompareXMLToArgvFiles()
set QEMUD_CMD_FLAG_PCI_MULTIBUS before calling qemuBuildCommandLine()
as the flags is not set by qemuCapsExtractVersionInfo().
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
qemu 0.13.0 (at least as built for Fedora 14, and also backported to
RHEL 6.0 qemu) supported an older syntax for a spicevmc channel; it's
not as flexible (it has an implicit name and hides the chardev
aspect), but now that we support spicevmc, we might as well target
both variants.
* src/qemu/qemu_capabilities.h (QEMUD_CMD_FLAG_DEVICE_SPICEVMC):
New flag.
* src/qemu/qemu_capabilities.c (qemuCapsParseDeviceStr): Set it
correctly.
* src/qemu/qemu_command.h (qemuBuildVirtioSerialPortDevStr): Drop
declaration.
* src/qemu/qemu_command.c (qemuBuildVirtioSerialPortDevStr): Alter
signature, check flag.
(qemuBuildCommandLine): Adjust caller and check flag.
* tests/qemuhelptest.c (mymain): Update test.
* tests/qemuxml2argvtest.c (mymain): New test.
* tests/qemuxml2argvdata/qemuxml2argv-channel-spicevmc-old.xml:
New file.
* tests/qemuxml2argvdata/qemuxml2argv-channel-spicevmc-old.args:
Likewise.
Adds <smartcard mode='passthrough' type='spicevmc'/>, which uses the
new <channel name='smartcard'/> of <graphics type='spice'>.
* docs/schemas/domain.rng: Support new XML.
* docs/formatdomain.html.in: Document it.
* src/conf/domain_conf.h (virDomainGraphicsSpiceChannelName): New
enum value.
(virDomainChrSpicevmcName): New enum.
(virDomainChrSourceDef): Distinguish spicevmc types.
* src/conf/domain_conf.c (virDomainGraphicsSpiceChannelName): Add
smartcard.
(virDomainSmartcardDefParseXML): Parse it.
(virDomainChrDefParseXML, virDomainSmartcardDefParseXML): Set
spicevmc name.
(virDomainChrSpicevmc): New enum conversion functions.
* src/libvirt_private.syms: Export new functions.
* src/qemu/qemu_command.c (qemuBuildChrChardevStr): Conditionalize
name.
* tests/qemuxml2argvtest.c (domain): New test.
* tests/qemuxml2argvdata/qemuxml2argv-smartcard-passthrough-spicevmc.args:
New file.
* tests/qemuxml2argvdata/qemuxml2argv-smartcard-passthrough-spicevmc.xml:
Likewise.
Inspired by https://bugzilla.redhat.com/show_bug.cgi?id=615757
Add a new character device backend for virtio serial channels that
activates the QEMU spice agent on the main channel using the vdagent
spicevmc connection. The <target> must be type='virtio', and supports
an optional name that specifies how the guest will see the channel
(for now, name must be com.redhat.spice.0).
<channel type='spicevmc'>
<target type='virtio'/>
<address type='virtio-serial' controller='1' bus='0' port='3'/>
</channel>
* docs/schemas/domain.rng: Support new XML.
* docs/formatdomain.html.in: Document it.
* src/conf/domain_conf.h (virDomainChrType): New enum value.
* src/conf/domain_conf.c (virDomainChr): Add spicevmc.
(virDomainChrDefParseXML, virDomainChrSourceDefParseXML)
(virDomainChrDefParseTargetXML): Parse and enforce proper use.
(virDomainChrSourceDefFormat, virDomainChrDefFormat): Format.
* src/qemu/qemu_command.c (qemuBuildChrChardevStr)
(qemuBuildCommandLine): Add qemu support.
* tests/qemuxml2argvtest.c (domain): New test.
* tests/qemuxml2argvdata/qemuxml2argv-channel-spicevmc.xml: New
file.
* tests/qemuxml2argvdata/qemuxml2argv-channel-spicevmc.args:
Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
qemu allows the user to choose what io storage api should be used,
either the default (threads) or native (linux aio) which in the latter
case can result in better performance.
Based on a patch originally by Matthias Dahl.
Red Hat Bugzilla #591703
Signed-off-by: Eric Blake <eblake@redhat.com>
In QEMU, the card itself is a PCI device, but it requires a codec
(either -device hda-output or -device hda-duplex) to actually output
sound. Specifying <sound model='ich6'/> gives us -device intel-hda
-device hda-duplex I think it's important that a simple <sound model='ich6'/>
sets up a useful codec, to have consistent behavior with all other sound cards.
This is basically Dan's proposal of
<sound model='ich6'>
<codec type='output' slot='0'/>
<codec type='duplex' slot='3'/>
</sound>
without the codec bits implemented.
The important thing is to keep a consistent API here, we don't want some
<sound> devs require tweaking codecs but not others. Steps I see to
accomplishing this:
- every <sound> device has a <codec type='default'/> (unless codecs are
manually specified)
- <codec type='none'/> is required to specify 'no codecs'
- new audio settings like mic=on|off could then be exposed in
<sound> or <codec> in a consistent manner for all sound models
v2:
Use model='ich6'
v3:
Use feature detection, from eblake
Set codec id, bus, and cad values
v4:
intel-hda isn't supported if -device isn't available
v5:
Comment spelling fixes
QEMU supports serving VNC over a unix domain socket rather than traditional
TCP host/port. This is specified with:
<graphics type='vnc' socket='/foo/bar/baz'/>
This provides better security access control than VNC listening on
127.0.0.1, but will cause issues with tools that rely on the lax security
(virt-manager in fedora runs as regular user by default, and wouldn't be
able to access a socket owned by 'qemu' or 'root').
Also not currently supported by any clients, though I have patches for
virt-manager, and virt-viewer should be simple to update.
v2:
schema: Make listen vs. socket a <choice>
https://bugzilla.redhat.com/show_bug.cgi?id=620363
When using -incoming stdio or -incoming exec:, qemu keeps the
stdin fd open long after the migration is complete. Not to
mention that exec:cat is horribly inefficient, by doubling the
I/O and going through a popen interface in qemu.
The new -incoming fd: of qemu 0.12.0 closes the fd after using
it, and allows us to bypass an intermediary cat process for
less I/O.
* src/qemu/qemu_command.h (qemuBuildCommandLine): Add parameter.
* src/qemu/qemu_command.c (qemuBuildCommandLine): Support
migration via fd: when possible. Consolidate migration handling
into one spot, now that it is more complex.
* src/qemu/qemu_driver.c (qemudStartVMDaemon): Update caller.
* tests/qemuxml2argvtest.c (mymain): Likewise.
* tests/qemuxml2argvdata/qemuxml2argv-restore-v2-fd.args: New file.
* tests/qemuxml2argvdata/qemuxml2argv-restore-v2-fd.xml: Likewise.
The xml watchdog dump option is converted to qemu watchdog pause arg
but it is not reasonable to convert it back from qemu watchdog pause
arg since there already is a xml watchdog pause option, so a test for
the dump option to convert it from arg to xml is not added.
Commit febc591683 introduced -vga none in
case no video card is included in domain XML. However, old qemu
versions do not support this and such domain cannot be successfully
started.
* src/qemu/qemu_conf.c (qemudExtractVersionInfo): Check for file
before executing it here, rather than in callers.
(qemudBuildCommandLine): Rewrite with virCommand.
* src/qemu/qemu_conf.h (qemudBuildCommandLine): Update signature.
* src/qemu/qemu_driver.c (qemuAssignPCIAddresses)
(qemudStartVMDaemon, qemuDomainXMLToNative): Adjust callers.
This patch allows for using custom scripts instead of /usr/bin/qemu
emulator in domain XML. To do so, one would specify relative path to the
custom script in <emulator/>. The path needs to be relative to
qemuxml2argvdata directory and it will be transparently made absolute in
runtime. The expected command line needs to contain the exact relative
path as was used in domain XML.
The problem is RelaxNG schema for domain XML only allows for absolute
path within <emulator/>. To workaround it, an extra '/' must be added at
the beginning of the path. That is, instead of "./qemu.sh" or
"../emulator/qemu.sh" one would use "/./qemu.sh" or
"/../emulator/qemu.sh". The extra slash is removed before further
processing. I don't like this workaround, it's very ugly but it's the
best option I was able to come up with. Relaxing domain XML schema is
not an option IMO.
In common with VNC, the QEMU driver configuration file is used
specify the host level TLS certificate location and a default
password / listen address
* src/qemu/qemu.conf: Add spice_listen, spice_tls,
spice_tls_x509_cert_dir & spice_password config params
* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Parsing of
spice config parameters and updating -spice arg generation
to use them
* tests/qemuxml2argvdata/qemuxml2argv-graphics-spice-rhel6.args,
tests/qemuxml2argvtest.c: Expand test case to cover driver
level configuration
This supports the -spice argument posted for review against
the latest upstream QEMU/KVM. This supports the bare minimum
config with port, TLS port & listen address. The x509 bits are
added in a later patch.
* src/qemu_conf.c, src/qemu_conf.h: Add SPICE flag. Check for
-spice availability. Format -spice arg for command line
* qemuhelptest.c: Add SPICE flag
* qemuxml2argvdata/qemuxml2argv-graphics-spice.args: Add <graphics>
for spice
* qemuxml2argvdata/qemuxml2argv-graphics-spice.xml: Add -spice arg
* qemuxml2argvtest.c: Add SPICE flag
This supports the '-vga qxl' parameter in upstream QEMU/KVM
which has SPICE support added. This isn't particularly useful
until you get the next patch for -spice support. Also note that
while the libvirt XML supports multiple video devices, this
patch only supports a single one. A later patch can add support
for 2nd, 3rd, etc PCI devices for QXL
* src/qemu/qemu_conf.h: Flag for QXL support
* src/qemu/qemu_conf.c: Probe for '-vga qxl' support and implement it
* tests/qemuxml2argvtest.c, tests/qemuxml2xmltest.c,
tests/qemuxml2argvdata/qemuxml2argv-graphics-spice.args,
tests/qemuxml2argvdata/qemuxml2argv-graphics-spice.xml: Test
case for generating spice args with RHEL6 kvm
So far, readonly=on option is used when qemu supports -device. However,
there are qemu versions which support readonly option with -drive
although they don't have support for -device.
* src/qemu/qemu_conf.c (qemuParseCommandLineSmp): Distinguish
between vcpus and maxvcpus, for new enough qemu.
* tests/qemuargv2xmltest.c (mymain): Add new test.
* tests/qemuxml2argvtest.c (mymain): Likewise.
* tests/qemuxml2xmltest.c (mymain): Likewise.
* tests/qemuxml2argvdata/qemuxml2argv-smp.args: New file.
Make use of the existing <filesystem> element to support plan9fs
filesystem passthrough in the QEMU driver
<filesystem type='mount'>
<source dir='/export/to/guest'/>
<target dir='/import/from/host'/>
</filesystem>
NB, the target is not actually a directory, it is merely a arbitrary
string tag that is exported to the guest as a hint for where to mount
it.
Add tests for auto memballon, implicit IDE, SCSI, virtio channel
controllers, and console/serial back compat.
Additionally, an explicit qemuxml2argvtest for scsi disks is added.
Signed-off-by: Cole Robinson <crobinso@redhat.com>
Add a new element to the <os> block:
<bootmenu enable="yes|no"/>
Which maps to -boot,menu=on|off on the QEMU command line.
I decided to use an explicit 'enable' attribute rather than just make the
bootmenu element boolean. This allows us to treat lack of a bootmenu element
as 'use hypervisor default'.
Thanks to DV for knocking together the Relax-NG changes
quickly for me.
Changes since v1:
- Change the domain.rng to correspond to the new schema
- Don't allocate caps->ns in testQemuCapsInit since it is a static table
Changes since v2:
- Change domain.rng to add restrictions on allowed environment names
Changes since v3:
- Remove a bogus comment in the tests
Signed-off-by: Chris Lalancette <clalance@redhat.com>
To allow compatibility with older QEMU PCI device slot assignment
it is necessary to explicitly track the balloon device in the
XML. This introduces a new device
<memballoon model='virtio|xen'/>
It can also have a PCI address, auto-assigned if necessary.
The memballoon will be automatically added to all Xen and QEMU
guests by default.
* docs/schemas/domain.rng: Add <memballoon> element
* src/conf/domain_conf.c, src/conf/domain_conf.h: parsing
and formatting for memballoon device. Always add a memory
balloon device to Xen/QEMU if none exists in XML
* src/libvirt_private.syms: Export memballoon model APIs
* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Honour the
PCI device address in memory balloon device
* tests/*: Update to test new functionality
The previous change which split -nodefconfig probing off
from -device broke the test case because it missed adding
the QEMUD_CMD_FLAG_NODEFCONFIG to the test
* src/util/bridge.c: Set QEMUD_CMD_FLAG_NODEFCONFIG for all
configs with QEMUD_CMD_FLAG_DEVICE set
The virtio serial changes broke the test suite because they forgot
to add the new address attribute to the domain XML schema. The
xml2xml test also broke because the XML no longer roundtrips. This
is due to testing of auto-addition of <controller> elements. Split
that test case off into a separate XML file to avoid breakage
* docs/schemas/domain.rng: Allow port number for virtio serial addresses
* tests/qemuxml2argvdata/qemuxml2argv-channel-virtio.args,
tests/qemuxml2argvdata/qemuxml2argv-channel-virtio.xml: Revert to
a simple config to avoid breaking xml2xml test
* tests/qemuxml2argvdata/qemuxml2argv-channel-virtio-auto.xml,
tests/qemuxml2argvdata/qemuxml2argv-channel-virtio-auto.args: Add
complex test case for auto-controller addition for xml2argv test
* tests/qemuxml2argvtest.c: Add channel-virtio-auto test
* Fixes per feedback from Dan and Daniel
* Added test datafiles
* Re-disabled JSON flags
* Added code to print the error policy attribute when generating XML
* Re-add empty tag
* src/qemu/qemu_conf.c: add the ",readonly=on" for read-only disks
and also parse it back in qemuParseCommandLineDisk()
* tests/qemuxml2argvtest.c
tests/qemuxml2argvdata/qemuxml2argv-disk-drive-readonly-disk.args
tests/qemuxml2argvdata/qemuxml2argv-disk-drive-readonly-disk.xml:
add a specific regression test
Allow an arbitrary timezone with QEMU by setting the $TZ environment
variable when launching QEMU
* src/qemu/qemu_conf.c: Set TZ environment variable if a timezone
is requested
* tests/qemuxml2argvtest.c: Add test case for timezones
* tests/qemuxml2argvdata/qemuxml2argv-clock-france.xml,
tests/qemuxml2argvdata/qemuxml2argv-clock-france.args: Data
for timezone tests
This allows QEMU guests to be started with an arbitrary clock
offset
The test case can't actually be enabled, since QEMU argv expects
an absolute timestring, and this will obviously change every
time the test runs :-( Hopefully QEMU will allow a relative
time offset in the future.
* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Use the -rtc arg
if available to support variable clock offset mode
* tests/qemuhelptest.c: Add QEMUD_CMD_FLAG_RTC for qemu 0.12.1
* qemuxml2argvdata/qemuxml2argv-clock-variable.args,
qemuxml2argvdata/qemuxml2argv-clock-variable.xml,
qemuxml2argvtest.c: Test case, except we can't actually enable
it yet.
Support virtio-serial controller and virtio channel in QEMU backend.
Will output
the following for virtio-serial controller:
-device
virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x4,max_ports=16,vectors=4
and the following for a virtio channel:
-chardev pty,id=channel0 \
-device
virtserialport,bus=virtio-serial0.0,chardev=channel0,name=org.linux-kvm.port.0
* src/qemu/qemu_conf.c: Add argument output for virtio
* tests/qemuxml2argvtest.c
tests/qemuxml2argvdata/qemuxml2argv-channel-virtio.args: Add test for
QEMU command line generation
Use the ATTRIBUTE_NONNULL annotation to mark some virConnectPtr
args as mandatory non-null so the compiler can warn of mistakes
* src/conf/domain_event.h: All virConnectPtr args must be non-null
* src/qemu/qemu_conf.h: qemudBuildCommandLine and
qemudNetworkIfaceConnect() must be given non-null connection
* tests/qemuxml2argvtest.c: Provide a non-null (dummy) connection to
qemudBuildCommandLine()
The QEMU flags are commonly stored as a signed or unsigned int,
allowing only 31 flags. This limit is rather close, so to aid
future patches, change it to a 64-bit int
* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h, src/qemu/qemu_driver.c,
tests/qemuargv2xmltest.c, tests/qemuhelptest.c, tests/qemuxml2argvtest.c:
Use 'unsigned long long' for QEMU flags
