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Jiri Denemark df13c0b477 qemu: Add support for guest CPU cache
This patch maps /domain/cpu/cache element into -cpu parameters:

- <cache mode='passthrough'/> is translated to host-cache-info=on
- <cache level='3' mode='emulate'/> is transformed into l3-cache=on
- <cache mode='disable'/> is turned in host-cache-info=off,l3-cache=off

Any other <cache> element is forbidden.

The tricky part is detecting whether QEMU supports the CPU properties.

The 'host-cache-info' property is introduced in v2.4.0-1389-ge265e3e480,
earlier QEMU releases enabled host-cache-info by default and had no way
to disable it. If the property is present, it defaults to 'off' for any
QEMU until at least 2.9.0.

The 'l3-cache' property was introduced later by v2.7.0-200-g14c985cffa.
Earlier versions worked as if l3-cache=off was passed. For any QEMU
until at least 2.9.0 l3-cache is 'off' by default.

QEMU 2.9.0 was the first release which supports probing both properties
by running device-list-properties with typename=host-x86_64-cpu. Older
QEMU releases did not support device-list-properties command for CPU
devices. Thus we can't really rely on probing them and we can just use
query-cpu-model-expansion QMP command as a witness.

Because the cache property probing is only reliable for QEMU >= 2.9.0
when both are already supported for quite a few releases, we let QEMU
report an error if a specific cache mode is explicitly requested. The
other mode (or both if a user requested CPU cache to be disabled) is
explicitly turned off for QEMU >= 2.9.0 to avoid any surprises in case
the QEMU defaults change. Any older QEMU already turns them off so not
doing so explicitly does not make any harm.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2017-04-27 22:41:10 +02:00
.gnulib@94386a1366 maint: update to latest gnulib 2017-01-10 12:54:54 -06:00
build-aux annotate all mocked functions with noinline 2017-04-19 10:51:51 +01:00
daemon remote: Fix possible use-after-free when sending event message 2017-04-25 07:26:36 -04:00
docs Add support for CPU cache specification 2017-04-27 22:07:14 +02:00
examples lib: Fix c99 style comments 2017-04-27 14:13:19 +02:00
gnulib build: drop hack for old mingw ssize_t 2016-07-12 08:57:13 -06:00
include/libvirt Add VIR_DOMAIN_JOB_OPERATION typed parameter 2017-04-27 15:06:40 +02:00
m4 locking: Add support for sanlock_strerror 2017-04-27 11:44:11 +02:00
po Refresh translations from zanata 2017-04-19 16:58:12 +01:00
src qemu: Add support for guest CPU cache 2017-04-27 22:41:10 +02:00
tests qemu: Add support for guest CPU cache 2017-04-27 22:41:10 +02:00
tools Add VIR_DOMAIN_JOB_OPERATION typed parameter 2017-04-27 15:06:40 +02:00
.ctags maint: Make ctags work out of the box 2013-07-18 08:47:21 +02:00
.dir-locals.el build: avoid tabs that failed syntax-check 2012-09-06 09:43:46 -06:00
.gitignore Add ability to generate man page describing key code names & values 2017-04-25 21:20:43 +01:00
.gitmodules util: switch over to use keycodemapdb GIT submodule 2017-04-25 21:14:18 +01:00
.mailmap maint: update .mailmap for recent contributions 2015-03-20 06:17:55 -06:00
.travis.yml Add travis build configuration 2017-04-19 10:51:51 +01:00
AUTHORS.in Change maintainers list 2016-02-12 13:10:05 +03:00
autogen.sh autogen.sh: Improve and generalize 2017-04-25 09:52:37 +02:00
bootstrap maint: update to latest gnulib 2017-01-10 12:54:54 -06:00
bootstrap.conf hvsupport: use a regex instead of XML::XPath 2016-07-19 18:42:44 +02:00
cfg.mk autogen.sh: Improve and generalize 2017-04-25 09:52:37 +02:00
ChangeLog-old Fix typos in src/* 2014-04-21 16:49:08 -06:00
config-post.h m4/virt-devmapper: use LIBVIRT_CHECK_(PKG|LIB) 2016-12-21 15:39:39 +01:00
configure.ac util: Add virNetDevSetCoalesce function 2017-04-21 13:29:39 +02:00
COPYING maint: follow recommended practice for using LGPL 2013-05-20 14:15:21 -06:00
COPYING.LESSER maint: Remove control characters from LGPL license file 2015-09-25 09:16:24 +02:00
HACKING Document preferred naming conventions 2017-03-10 11:28:56 +00:00
libvirt-admin.pc.in Add libvirt-admin library 2015-06-16 13:46:20 +02:00
libvirt-lxc.pc.in Add pkg-config files for libvirt-qemu & libvirt-lxc 2014-06-23 16:17:27 +01:00
libvirt-qemu.pc.in Add pkg-config files for libvirt-qemu & libvirt-lxc 2014-06-23 16:17:27 +01:00
libvirt.pc.in Add pkg-config files for libvirt-qemu & libvirt-lxc 2014-06-23 16:17:27 +01:00
libvirt.spec.in Add ability to generate man page describing key code names & values 2017-04-25 21:20:43 +01:00
Makefile.am Drop autobuild.sh 2017-04-13 19:03:46 +02:00
Makefile.nonreentrant cfg.mk: use a single regex for all non-reentrant functions 2016-06-15 15:00:56 +02:00
mingw-libvirt.spec.in Add ability to generate man page describing key code names & values 2017-04-25 21:20:43 +01:00
README Correct typos in the documentation (Atsushi SAKAI) 2008-01-24 10:15:13 +00:00
README-hacking docs: update README-hacking 2014-05-06 16:20:24 -06:00
run.in Add PKG_CONFIG_PATH to run.in script. 2014-06-26 14:32:35 +01:00
TODO Update todo list file to point at bugzilla/website 2010-10-13 16:45:26 +01:00

         LibVirt : simple API for virtualization

  Libvirt is a C toolkit to interact with the virtualization capabilities
of recent versions of Linux (and other OSes). It is free software
available under the GNU Lesser General Public License. Virtualization of
the Linux Operating System means the ability to run multiple instances of
Operating Systems concurrently on a single hardware system where the basic
resources are driven by a Linux instance. The library aim at providing
long term stable C API initially for the Xen paravirtualization but
should be able to integrate other virtualization mechanisms if needed.

Daniel Veillard <veillard@redhat.com>