[PATCH 0/6] KVM: Optimize MMU notifier's THP page invalidation -v3

[Takuya Yoshikawa <yoshikawa.takuya@xxxxxxxxxxxxx>]

Updated patch 3 and 6 so that unmap handler be called with exactly same
rmap arguments as before, even if kvm_handle_hva_range() is called with
unaligned [start, end).

Please see the comments I added there.

	Takuya


Takuya Yoshikawa (6):
  KVM: MMU: Use __gfn_to_rmap() to clean up kvm_handle_hva()
  KVM: Introduce hva_to_gfn_memslot() for kvm_handle_hva()
  KVM: MMU: Make kvm_handle_hva() handle range of addresses
  KVM: Introduce kvm_unmap_hva_range() for kvm_mmu_notifier_invalidate_range_start()
  KVM: Separate rmap_pde from kvm_lpage_info->write_count
  KVM: MMU: Avoid handling same rmap_pde in kvm_handle_hva_range()


 arch/powerpc/include/asm/kvm_host.h |    2 +
 arch/powerpc/kvm/book3s_64_mmu_hv.c |   47 +++++++++++++++----
 arch/x86/include/asm/kvm_host.h     |    3 +-
 arch/x86/kvm/mmu.c                  |   83 +++++++++++++++++++++++------------
 arch/x86/kvm/x86.c                  |   11 +++++
 include/linux/kvm_host.h            |    8 +++
 virt/kvm/kvm_main.c                 |    3 +-
 7 files changed, 116 insertions(+), 41 deletions(-)


>From v2:

I added further optimization based on Avi's advice and my rmap_pde work.
 - patch [5-6]

The new test result was impressively good, see below, and THP page
invalidation was more than 5 times faster on my x86 machine.

Before:
  ...
  19.852 us  |  __mmu_notifier_invalidate_range_start();
  28.033 us  |  __mmu_notifier_invalidate_range_start();
  19.066 us  |  __mmu_notifier_invalidate_range_start();
  44.715 us  |  __mmu_notifier_invalidate_range_start();
  31.613 us  |  __mmu_notifier_invalidate_range_start();
  20.659 us  |  __mmu_notifier_invalidate_range_start();
  19.979 us  |  __mmu_notifier_invalidate_range_start();
  20.416 us  |  __mmu_notifier_invalidate_range_start();
  20.632 us  |  __mmu_notifier_invalidate_range_start();
  22.316 us  |  __mmu_notifier_invalidate_range_start();
  ...

After:
  ...
  4.089 us   |  __mmu_notifier_invalidate_range_start();
  4.096 us   |  __mmu_notifier_invalidate_range_start();
  3.560 us   |  __mmu_notifier_invalidate_range_start();
  3.376 us   |  __mmu_notifier_invalidate_range_start();
  3.772 us   |  __mmu_notifier_invalidate_range_start();
  3.353 us   |  __mmu_notifier_invalidate_range_start();
  3.332 us   |  __mmu_notifier_invalidate_range_start();
  3.332 us   |  __mmu_notifier_invalidate_range_start();
  3.332 us   |  __mmu_notifier_invalidate_range_start();
  3.337 us   |  __mmu_notifier_invalidate_range_start();
  ...
-- 
1.7.5.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/