Re: [PATCH] Replace kvm io delay pv-ops with linux magic

[Jeremy Fitzhardinge <jeremy@goop.org>]

On 11/20/09 09:59, Alexander Graf wrote:
>
> On 20.11.2009, at 02:54, Jeremy Fitzhardinge wrote:
>
>> On 11/20/09 07:58, Alexander Graf wrote:
>>>
>>> Am 19.11.2009 um 23:55 schrieb Jeremy Fitzhardinge <jeremy@goop.org>:
>>>
>>>> On 11/18/09 20:56, Alexander Graf wrote:
>>>>> Currently we use pv-ops to tell linux not to do anything on io_delay.
>>>>>
>>>>> While the basic idea is good IMHO, I don't see why we would need
>>>>> pv-ops
>>>>> for that. The io delay function already has a switch that can do
>>>>> nothing
>>>>> if you're so inclined.
>>>>>
>>>>> So here's a patch (stacked on top of the previous pv-ops series) that
>>>>> removes the io delay pv-ops hook and just sets the native io delay
>>>>> variable instead.
>>>>>
>>>>
>>>> Can you just get rid of the io_delay op altogether?  If KVM doesn't
>>>> need
>>>> it, then nobody does.
>>>
>>> Sure, can do. That'd be a separate patch though.
>>
>> Yep.  A patch each for VMI and Xen to remove the dependency, and a final
>> patch to remove the op.  Hm, looks like VMI has a specific ROM call for
>> io_delay; I wonder what it does.
>
> Oh so it's actually using it? Feel like doing the removal then? I
> don't really want to mess with VMI code :-)

I would post the patch and see if Alok naks it.  But I somehow doubt
vmware is doing anything profound with that call.

    J