lkml.org 
[lkml]   [2011]   [Feb]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 7/7] KVM: MMU: cache guest page number to guest frame number
On 02/23/2011 03:38 AM, Xiao Guangrong wrote:
> On 02/22/2011 10:32 PM, Avi Kivity wrote:
> > On 02/22/2011 10:16 AM, Xiao Guangrong wrote:
> >> Cache guest page number to guest frame number to avoid walk guest page table
> >> frequently, the 'vtlb' idea is from Xen.
> >>
> >> Note:
> >> we can't use vtlb in ept guests since the guest tlb invalid operation is not
> >> intercept(reload CR3, invlpg), also can't used in L2 nnpt guest for the same
> >> reason, but we can used it to cache L1's npt page table.
> >>
> >
> > I'm not so hot about introducing a new mechanism strictly for older hosts... EPT exists in three generations of Intel processors now (Sandy Bridge, Westmere, and Nehalem), and NPT is significantly older.
> >
>
> Um...so, do we should stop the new features for softmmu, only bug fix is welcome? :-)

No. There is always a tradeoff between features and complexity. What
I'm saying is that I want to shift the tradeoff, for older processors,
towards reducing complexity. An improvement that is very simple, or
gives very large gains, will be accepted. A complex improvement that
gives small gains may be rejected (but if it's for newer processors, it
may be accepted). It's a way for the maintainers to manage the ever
growing complexity.

--
error compiling committee.c: too many arguments to function



\
 
 \ /
  Last update: 2011-02-23 10:31    [W:0.384 / U:1.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site