VIR_DOMAIN_XML_UPDATE_CPU flag for virDomainGetXMLDesc may be used to
get updated custom mode guest CPU definition in case it depends on host
CPU. This patch implements the same behavior for host-model and
host-passthrough CPU modes.
The mode can be either of "custom" (default), "host-model",
"host-passthrough". The semantics of each mode is described in the
following examples:
- guest CPU is a default model with specified topology:
<cpu>
<topology sockets='1' cores='2' threads='1'/>
</cpu>
- guest CPU matches selected model:
<cpu mode='custom' match='exact'>
<model>core2duo</model>
</cpu>
- guest CPU should be a copy of host CPU as advertised by capabilities
XML (this is a short cut for manually copying host CPU specification
from capabilities to domain XML):
<cpu mode='host-model'/>
In case a hypervisor does not support the exact host model, libvirt
automatically falls back to a closest supported CPU model and
removes/adds features to match host. This behavior can be disabled by
<cpu mode='host-model'>
<model fallback='forbid'/>
</cpu>
- the same as previous returned by virDomainGetXMLDesc with
VIR_DOMAIN_XML_UPDATE_CPU flag:
<cpu mode='host-model' match='exact'>
<model fallback='allow'>Penryn</model> --+
<vendor>Intel</vendor> |
<topology sockets='2' cores='4' threads='1'/> + copied from
<feature policy='require' name='dca'/> | capabilities XML
<feature policy='require' name='xtpr'/> |
... --+
</cpu>
- guest CPU should be exactly the same as host CPU even in the aspects
libvirt doesn't model (such domain cannot be migrated unless both
hosts contain exactly the same CPUs):
<cpu mode='host-passthrough'/>
- the same as previous returned by virDomainGetXMLDesc with
VIR_DOMAIN_XML_UPDATE_CPU flag:
<cpu mode='host-passthrough' match='minimal'>
<model>Penryn</model> --+ copied from caps
<vendor>Intel</vendor> | XML but doesn't
<topology sockets='2' cores='4' threads='1'/> | describe all
<feature policy='require' name='dca'/> | aspects of the
<feature policy='require' name='xtpr'/> | actual guest CPU
... --+
</cpu>
In case a hypervisor doesn't support the exact CPU model requested by a
domain XML, we automatically fallback to a closest CPU model the
hypervisor supports (and make sure we add/remove any additional features
if needed). This patch adds 'fallback' attribute to model element, which
can be used to disable this automatic fallback.
This patch adds XML definitions for guest NUMA specification and contains
routines to parse the same. The guest NUMA specification looks like this:
<cpu>
...
<topology sockets='2' cores='4' threads='2'/>
<numa>
<cell cpus='0-7' memory='512000'/>
<cell cpus='8-15' memory='512000'/>
</numa>
...
</cpu>
Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Auto-indent makes life a bit easier; this patch also drops unused
arguments and replaces a misspelled flag name with two entry points
instead, so that callers don't have to worry about how much spacing
is present when embedding cpu elements.
* src/conf/cpu_conf.h (virCPUFormatFlags): Delete.
(virCPUDefFormat): Drop unused argument.
(virCPUDefFormatBuf): Alter signature.
(virCPUDefFormatBufFull): New prototype.
* src/conf/cpu_conf.c (virCPUDefFormatBuf): Split...
(virCPUDefFormatBufFull): ...into new function.
(virCPUDefFormat): Adjust caller.
* src/conf/domain_conf.c (virDomainDefFormatInternal): Likewise.
* src/conf/capabilities.c (virCapabilitiesFormatXML): Likewise.
* src/cpu/cpu.c (cpuBaselineXML): Likewise.
* tests/cputest.c (cpuTestCompareXML): Likewise.
To allow a client app to pass in custom XML during migration
of a guest it is neccessary to ensure the guest ABI remains
unchanged. The virDomainDefCheckABIStablity method accepts
two virDomainDefPtr structs and compares everything in them
that could impact the guest machine ABI
* src/conf/domain_conf.c, src/conf/domain_conf.h,
src/libvirt_private.syms: Add virDomainDefCheckABIStablity
* src/conf/cpu_conf.c, src/conf/cpu_conf.h: Add virCPUDefIsEqual
* src/util/sysinfo.c, src/util/sysinfo.h: Add virSysinfoIsEqual
By specifying <vendor> element in CPU requirements a guest can be
restricted to run only on CPUs by a given vendor. Host CPU vendor is
also specified in capabilities XML.
The vendor is checked when migrating a guest but it's not forced, i.e.,
guests configured without <vendor> element can be freely migrated.
The virConnectPtr is no longer required for error reporting since
that is recorded in a thread local. Remove use of virConnectPtr
from all APIs in cpu_conf.{h,c} and update all callers to
match
* include/libvirt/virterror.h src/util/virterror.c: add new domain
VIR_FROM_CPU for errors
* src/conf/cpu_conf.c src/conf/cpu_conf.h: new parsing module
* src/Makefile.am proxy/Makefile.am: include new files
* src/conf/capabilities.[ch] src/conf/domain_conf.[ch]: reference
new code
* src/libvirt_private.syms: private export of new entry points
