Re: [PATCH 3/7] KVM-HV: KVM Steal time implementation

Glauber Costa
2011-06-20T12:43:00Z

On 06/20/2011 05:02 AM, Avi Kivity wrote:
> On 06/20/2011 10:21 AM, Gleb Natapov wrote:
>> On Sun, Jun 19, 2011 at 04:02:22PM +0300, Avi Kivity wrote:
>> > On 06/19/2011 03:59 PM, Gleb Natapov wrote:
>> > >On Sun, Jun 19, 2011 at 03:35:58PM +0300, Avi Kivity wrote:
>> > >> On 06/15/2011 12:09 PM, Gleb Natapov wrote:
>> > >> >>
>> > >> >> Actually, I'd expect most read/writes to benefit from caching,
>> no?
>> > >> >> So why don't we just rename kvm_write_guest_cached() to
>> > >> >> kvm_write_guest(), and the few places - if any - that need to
>> force
>> > >> >> transversing of the gfn mappings, get renamed to
>> > >> >> kvm_write_guest_uncached ?
>> > >> >>
>> > >> >Good idea. I do not see any places where
>> kvm_write_guest_uncached is
>> > >> >needed from a brief look. Avi?
>> > >> >
>> > >>
>> > >> kvm_write_guest_cached() needs something to supply the cache, and
>> > >> needs recurring writes to the same location. Neither of these are
>> > >> common (for example, instruction emulation doesn't have either).
>> > >>
>> > >Correct. Missed that. So what about changing steal time to use
>> > >kvm_write_guest_cached()?
>> >
>> > Makes sense, definitely. Want to post read_guest_cached() as well?
>> >
>> Glauber can you write read_guest_cached() as part of your series (should
>> be trivial), or do you want me to do it? I do not have a code to test it
>> with though :)
>
> Yes.
>
> (you can write it, and Glauber can include it in the series)
>
Write it, handle me the patch, I'll include it and test it.