Re: [PATCHv5 0/4] improve speed of "rep ins" emulation

["Richard W.M. Jones" <rjones@redhat.com>]

On Mon, Jul 30, 2012 at 05:38:17PM +0300, Gleb Natapov wrote:
> And now for something completely different.
> 
> So this series (or rather the last patch of it) takes different approach
> to "rep ins" optimization. Instead of writing separate fast path for
> it do the fast path inside emulator itself. This way nobody can say the
> code is not reused!
> 
> Patch 1,2 are now, strictly speaking, not needed, but I think this is still
> nice cleanup and, in case of patch 1, eliminates some ifs at each KVM_RUN ioctl.
>  
> Gleb Natapov (4):
>   Provide userspace IO exit completion callback.
>   KVM: emulator: make x86 emulation modes enum instead of defines
>   KVM: emulator: string_addr_inc() cleanup
>   KVM: emulator: optimize "rep ins" handling.
> 
>  arch/x86/include/asm/kvm_emulate.h |   26 +++++-----
>  arch/x86/include/asm/kvm_host.h    |    1 +
>  arch/x86/kvm/emulate.c             |   48 ++++++++++++++-----
>  arch/x86/kvm/x86.c                 |   92 +++++++++++++++++++++---------------
>  4 files changed, 104 insertions(+), 63 deletions(-)

I tested this patch series and it really helped to improve the
performance of loading the libguestfs -kernel and -initrd:

  https://bugzilla.redhat.com/show_bug.cgi?id=847546

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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