[libvirt] [RFC PATCH v2 0/4] Libvirt for PowerPC

[Stefan Berger]

On 11/14/2011 09:43 AM, Prerna Saxena wrote:
> Hi,
> Recent development in KVM for 64-bit Power ISA Book3S machines, allows
> users to run multiple KVM guest instances on POWER7 and PPC970
> processor based systems.  Also qemu-system-ppc64 has been enhanced to
> support a new machine type "pseries" suitable for Power Book3S machines.
> This addition effectively brings the KVM+qemu combination to run
> multiple guest instances on a Power Book3S machine.
>
> Libvirt continues to be the key interface to configure and manage the
> KVM guest instances on x86.  This patch set is an effort to enable
> libvirt to support KVM guest configuration and management on Power Book3S
> machines.
>
> Based on community discussion around the earlier version, this patch
> series augments the present 'kvm' driver to support PowerPC-KVM based
> guests. Since some of the supported devices vary between architectures,
> the code is now reworked to dynamically choose the correct handler
> function based on guest domain architecture at runtime (def->os.arch).
>
> This patch series consists of 4 patches :
> Patch 1/4 : Use sysfs to gather host topology. Presently libvirt
>              depends on /proc/cpuinfo gather CPU, cores, threads, etc
>              This is highly architecture dependent. A alternative is
>              to use sysfs, which provides a platform-neutral interface
>              to parse CPU topology.
> Patch 2/4 : Add PowerPC CPU Driver
> Patch 3/4 : Add support for qemu-system-ppc64
> Patch 4/4 : Refactor qemu commmand-line generation to separate out arch-
>              specific options from generic command line.
>
> Changelog from v1:
> * Patches 1,2,3 unchanged ; The hacks in Patch 4 of v1 have been
>    replaced by a new patch to neatly select arch-specific features.
>
> Awaiting comments and feedback,
A few quick comments:

Run 'make syntax-check'. Some cleanup needs to be done.

Also use ATTRIBUTE_UNUSED on variables that are not use, like here when 
compiling on x86.

cpu/cpu_powerpc.c: In function 'PowerPCDecode':
cpu/cpu_powerpc.c:50:28: warning: unused parameter 'cpu' 
[-Wunused-parameter]
cpu/cpu_powerpc.c:51:36: warning: unused parameter 'data' 
[-Wunused-parameter]
cpu/cpu_powerpc.c:52:28: warning: unused parameter 'models' 
[-Wunused-parameter]
cpu/cpu_powerpc.c:53:28: warning: unused parameter 'nmodels' 
[-Wunused-parameter]
cpu/cpu_powerpc.c:54:27: warning: unused parameter 'preferred' 
[-Wunused-parameter]
cpu/cpu_powerpc.c: At top level:
cpu/cpu_powerpc.c:75:5: warning: initialization from incompatible 
pointer type
cpu/cpu_powerpc.c: In function 'PowerPCDataFree':
cpu/cpu_powerpc.c:66:1: warning: control reaches end of non-void 
function [-Wreturn-type]

nodeinfo.c: In function 'linuxNodeInfoCPUPopulate':
nodeinfo.c:287:5: warning: suggest parentheses around assignment used as 
truth value [-Wparentheses]
nodeinfo.c:202:36: warning: unused parameter 'need_hyperthreads' 
[-Wunused-parameter]

qemu/qemu_command.c: In function 'qemuBuildX86CommandLine':
qemu/qemu_command.c:5250:17: warning: too many arguments for format 
[-Wformat-extra-args]
qemu/qemu_command.c:5201:41: warning: unused parameter 'conn' 
[-Wunused-parameter]
qemu/qemu_command.c: In function 'qemuBuildCommandLine':
qemu/qemu_command.c:3264:35: warning: 'qemuCmdFunc' may be used 
uninitialized in this function [-Wuninitialized]

Some of the code (part 4) when I looked seemed to have indentation problems.

   Stefan