Re: [PATCH] x86: svm: make wbinvd faster

[Radim KrÄmÃÅ]

2015-03-09 20:28-0300, Marcelo Tosatti:
> On Fri, Feb 27, 2015 at 06:19:18PM -0600, Joel Schopp wrote:
> > From: David Kaplan <David.Kaplan@xxxxxxx>
> > No need to re-decode WBINVD since we know what it is from the intercept.
> > 
> > Signed-off-by: David Kaplan <David.Kaplan@xxxxxxx>
> > [extracted from larger unlrelated patch, forward ported, tested]
> > Signed-off-by: Joel Schopp <joel.schopp@xxxxxxx>
> 
> Can't you disable the intercept if need_emulate_wbinvd(vcpu) == false? 

I don't think we want to:  it should be faster to intercept and ignore
than to invalidate all caches.  The exit doesn't affect other physical
cores and costs just about 10(?) L3 cache misses.
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