Re: [Qemu-devel] [PATCH v3 00/18] ppc/pnv: add XIVE support for KVM guests

["Cédric Le Goater" <clg@kaod.org>]

On 18/09/2019 07:44, David Gibson wrote:
> On Tue, Sep 17, 2019 at 01:54:24PM +0200, Cédric Le Goater wrote:
>> On 31/07/2019 16:12, Cédric Le Goater wrote:
>>> Hello,
>>>
>>> The QEMU PowerNV machine emulates a baremetal OpenPOWER system and
>>> acts as an hypervisor (L0). Supporting emulation of KVM to run guests
>>> (L1) requires a few more extensions, among which guest support for the
>>> XIVE interrupt controller on POWER9 processor.
>>>
>>> The following changes add new per-CPU PowerNV machines and extend the
>>> XIVE models with the new XiveFabric and XivePresenter interfaces to
>>> provide support for XIVE escalations and interrupt resend. This
>>> mechanism is used by XIVE to notify the hypervisor that a vCPU is not
>>> dispatched on a HW thread. Tested on a QEMU PowerNV machine and a
>>> simple QEMU pseries guest doing network on a local bridge.
>>>
>>> The XIVE interrupt controller offers a way to increase the XIVE
>>> resources per chip by configuring multiple XIVE blocks on a chip. This
>>> is not currently supported by the model. However, some configurations,
>>> such as OPAL/skiboot, use one block-per-chip configuration with some
>>> optimizations. One of them is to override the hardwired chip ID by the
>>> block id in the PowerBUS operations and for CAM line compares. This
>>> patchset improves the support for this setup. Tested with 4 chips.
>>
>> David,
>>
>> Do you want me to resend this patchset ? or you just didn't have time
>> to look at it ?  
> 
> Mostly, I just haven't had time.  I'm also finding the patches pretty
> difficult to read and review.  I don't think that's an indication
> they're bad, just that what they're doing is necessarily complex, but
> it's still made it hard to tackle them.

I will try to split the initial patches on the presenter a little more.


>> Patch 16 has changed a little since. The get_block_id() handler has 
>> moved to the XiveRouterClass.
> 
> You, might as well repost, so I'm looking at the latest stuff.  I
> can't promise I'll be able to look at the new set terribly soon
> though.

ok.

thanks,

C.