KVM: x86/mmu: Revert "Revert "KVM: MMU: reclaim the zapped-obsolete page first""

Now that the fast invalidate mechanism has been reintroduced, restore
the performance tweaks for fast invalidation that existed prior to its
removal.

Paraphrashing the original changelog:

  Introduce a per-VM list to track obsolete shadow pages, i.e. pages
  which have been deleted from the mmu cache but haven't yet been freed.
  When page reclaiming is needed, zap/free the deleted pages first.

This reverts commit 52d5dedc79bdcbac2976159a172069618cf31be5.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 78f0a919173e68c7c51fbb01e3f4fe3d8d112ff5..53e0b956ed3c3edfd14a3eacf42a91c4c7e843a9 100644 (file)
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -865,6 +865,7 @@ struct kvm_arch {
         * Hash table of struct kvm_mmu_page.
         */
        struct list_head active_mmu_pages;
+       struct list_head zapped_obsolete_pages;
        struct kvm_page_track_notifier_node mmu_sp_tracker;
        struct kvm_page_track_notifier_head track_notifier_head;