Hi Alex,
    I tested your code changes for two problems
1. MSIX vectors allocation for FreeBSD Guest
    Tested the allocation of MSI-X allocation happening for both
FreeBSD-9.0 (also tested 8.2) and Linux guest.
     Also tried multiple restart of the guests to see if the hosts
still maintains those allocations. With Linux
     as guest I could pass traffic. Though interrupt allocation worked
the FreeBSD could to pass traffic. The FreeBSD
     driver seems to be broken(atleast when running in guest).

2. Guest MSI-X smp_affinity fix.
     The smp_affinity configured in guest is honoured. The traffic
distribution is uniform. When smp affinity is configured
     in host and guest properly this fix provides multi queue and
hence multi core traffic distribution in both host and
     guest. The result is good packet throughput.

Thanks for the the much needed fixes.

-Shashidhar

On Mon, Feb 6, 2012 at 10:59 PM, Alex Williamson
<alex.william...@redhat.com> wrote:
> On Mon, 2012-02-06 at 21:25 +0530, Shashidhar Patil wrote:
>> HI Alex,
>>      I can give it a try. Please send me all patches as one file if possible.
>> I was about to report yet another problem with Guest MSI-X smp affinity
>> not being honoured by KVM while injecting interrupts. Its again in the 
>> context
>> of 82599 device (tried with Linux as guest). I had a hunch that the MSI-X 
>> vector
>> data which gets modified when SMP affinity is not tracked by the qemu_kvm.
>> So the interrupt injection was done in load balancing fashion. Because of 
>> this
>> interrupt LB in guest VCPUs I saw that packets for all the queues were 
>> processed
>> by one VCPU instead 2 or 4 available.
>> Anyway I will test the the MSI-X affinity fix also and get back with results.
>> And I hope 82599 send/receive works. Thanks for your help.
>
> I pushed the v2 version to github, so you can grab it from here for
> testing:
>
> git://github.com/awilliam/qemu-kvm.git
>
> Branch pci-assign-msix.  Thanks,
>
> Alex
>
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