Re: [PATCH v3 5/6] arm/dom0less: assign dom0less guests to cpupools

[Luca Fancellu <Luca.Fancellu@xxxxxxx>]

+ maintainer golang, libs, ocaml, python bindings

> On 18 Mar 2022, at 16:18, Julien Grall <julien@xxxxxxx> wrote:
> 
> Hi,
> 
> On 18/03/2022 15:25, Luca Fancellu wrote:
>> Introduce domain-cpupool property of a xen,domain device tree node,
>> that specifies the cpupool device tree handle of a xen,cpupool node
>> that identifies a cpupool created at boot time where the guest will
>> be assigned on creation.
>> Add member to the xen_domctl_createdomain public interface so the
>> XEN_DOMCTL_INTERFACE_VERSION version is bumped.
>> Add public function to retrieve a pool id from the device tree
>> cpupool node.
>> Update documentation about the property.
>> Signed-off-by: Luca Fancellu <luca.fancellu@xxxxxxx>
>> ---
>> Changes in v3:
>> - Use explicitely sized integer for struct xen_domctl_createdomain
>>   cpupool_id member. (Stefano)
>> - Changed code due to previous commit code changes
>> Changes in v2:
>> - Moved cpupool_id from arch specific to common part (Juergen)
>> - Implemented functions to retrieve the cpupool id from the
>>   cpupool dtb node.
>> ---
>>  docs/misc/arm/device-tree/booting.txt |  5 +++++
>>  xen/arch/arm/domain_build.c           | 14 +++++++++++++-
>>  xen/common/boot_cpupools.c            | 24 ++++++++++++++++++++++++
>>  xen/common/domain.c                   |  2 +-
>>  xen/include/public/domctl.h           |  4 +++-
>>  xen/include/xen/sched.h               |  9 +++++++++
> 
> This patch doesn't seem to contain any change in tools. So...
> 
>>          if ( (err = late_hwdom_init(d)) != 0 )
>> diff --git a/xen/include/public/domctl.h b/xen/include/public/domctl.h
>> index b85e6170b0aa..2f4cf56f438d 100644
>> --- a/xen/include/public/domctl.h
>> +++ b/xen/include/public/domctl.h
>> @@ -38,7 +38,7 @@
>>  #include "hvm/save.h"
>>  #include "memory.h"
>>  -#define XEN_DOMCTL_INTERFACE_VERSION 0x00000014
>> +#define XEN_DOMCTL_INTERFACE_VERSION 0x00000015
>>    /*
>>   * NB. xen_domctl.domain is an IN/OUT parameter for this operation.
>> @@ -106,6 +106,8 @@ struct xen_domctl_createdomain {
>>      /* Per-vCPU buffer size in bytes.  0 to disable. */
>>      uint32_t vmtrace_size;
>>  +    uint32_t cpupool_id;
> 
> ... will the tools (e.g. golang bindings, libxl,..) always zero 
> xen_domctl_createdomain?
> 
> I also think we may need to regenerate the golang bindings.

I’ve checked the occurrences of struct xen_domctl_createdomain in tools/ and I 
see it is
always initialised using designated initializers so (correct me if I’m wrong) 
any non specified
field should be zero.

I tried to check if I need and how to regenerate the golang bindings, I didn’t 
find documentation
to do that, I’ve added some maintainer to this reply that hopefully can help me 
to understand
If I’ve missed something in this patch modifying struct xen_domctl_createdomain.

Cheers,
Luca

> 
> Cheers,
> 
> -- 
> Julien Grall