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
virt-p2v converts physical machines to virtual machines.  Boot with a
live CD or over the network (PXE) and turn machines into Xen guests.
http://et.redhat.com/~rjones/virt-p2v