Re: [libvirt] [RFC PATCH 2/4] powerpc: Add cpu driver for powerpc host
On Mon, 10 Oct 2011 10:57:34 +0100
"Daniel P. Berrange" <berrange(a)redhat.com> wrote:
On Sat, Oct 08, 2011 at 12:12:46AM +0530, Prerna Saxena wrote:
> This part of code primarily compares host and guest CPUs of a given
> architecture for feature compatibility. x86 makes this choice based on
> CPUID comparison.
> Presently the PowerPC code has stubs to just get a 'pseries' guest to
> boot. It would be augmented going forward, to do a detailed feature
> comparison between guest and host CPUs on powerpc.
> This part of code is presently well-classified into different
> architectures, and consequently does not need reorganizing.
>
> ---
> src/Makefile.am | 3 +-
> src/cpu/cpu.c | 2 +
> src/cpu/cpu_powerpc.c | 81 +++++++++++++++++++++++++++++++++++++++++++++++++
> src/cpu/cpu_powerpc.h | 32 +++++++++++++++++++
> 4 files changed, 117 insertions(+), 1 deletions(-)
> create mode 100644 src/cpu/cpu_powerpc.c
> create mode 100644 src/cpu/cpu_powerpc.h
The idea here looks fine.
Thanks.
> diff --git a/src/cpu/cpu_powerpc.c b/src/cpu/cpu_powerpc.c
> new file mode 100644
> index 0000000..6ceedc3
> --- /dev/null
> +++ b/src/cpu/cpu_powerpc.c
> +
> +#define VIR_FROM_THIS VIR_FROM_CPU
> +
> +static const char *archs[] = { "ppc64" };
How about 'ppc' too ?
> +static union cpuData *
> +PowerPCNodeData(void)
> +{
> + union cpuData *data;
> +
> + if (VIR_ALLOC(data) < 0) {
> + virReportOOMError();
> + return NULL;
> + }
> +
> + return data;
> +}
> +
> +
> +static int
> +PowerPCDecode(virCPUDefPtr cpu,
> + const union cpuData *data,
> + const char **models,
> + unsigned int nmodels,
> + const char *preferred)
Need to annotate these with 'ATTRIBUTE_UNUSED' to avoid compiler
warnings.
Will do.
> +{
> + return 0;
> +}
> +
> +static int
Should be 'void'
Thanks for pointing this out, will fix it.
> +PowerPCDataFree(union cpuData *data)
> +{
> + if (data == NULL)
> + return 0;
> +
> + VIR_FREE(data);
> +}
> +
> +struct cpuArchDriver cpuDriverPowerPC = {
> + .name = "ppc64",
> + .arch = archs,
> + .narch = ARRAY_CARDINALITY(archs),
> + .compare = NULL,
> + .decode = PowerPCDecode,
> + .encode = NULL,
> + .free = PowerPCDataFree,
> + .nodeData = PowerPCNodeData,
> + .guestData = NULL,
> + .baseline = NULL,
> + .update = NULL,
> + .hasFeature = NULL,
> +};
Should we have another copy for 'ppc' arch too ?
At present, I've tested this with KVM for Power ISA Book3S machines,
which introduces a new machine type "pseries" based on the ppc64
architecture. Extending this to 'ppc' architecture should be a trivial
effort -- I'll add that as soon as I get to test it.
--
Prerna Saxena
Linux Technology Centre,
IBM Systems and Technology Lab,
Bangalore, India