Commit 88810413 authored by David Matlack's avatar David Matlack Committed by Paolo Bonzini
Browse files

KVM: x86/mmu: Avoid memslot lookup in page_fault_handle_page_track 



Now that kvm_page_fault has a pointer to the memslot it can be passed
down to the page tracking code to avoid a redundant slot lookup.

No functional change intended.

Signed-off-by: default avatarDavid Matlack <dmatlack@google.com>
Message-Id: <20210813203504.2742757-5-dmatlack@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent e710c5f6

arch/x86/include/asm/kvm_page_track.h

+2 −0
Original line number Diff line number Diff line
@@ -61,6 +61,8 @@ void kvm_slot_page_track_remove_page(struct kvm *kvm, 
				     enum kvm_page_track_mode mode);

bool kvm_page_track_is_active(struct kvm_vcpu *vcpu, gfn_t gfn,

			      enum kvm_page_track_mode mode);

bool kvm_slot_page_track_is_active(struct kvm_memory_slot *slot, gfn_t gfn,

				   enum kvm_page_track_mode mode);



void

kvm_page_track_register_notifier(struct kvm *kvm,

arch/x86/kvm/mmu/mmu.c

+1 −1
Original line number Diff line number Diff line
@@ -3819,7 +3819,7 @@ static bool page_fault_handle_page_track(struct kvm_vcpu *vcpu, 
	 * guest is writing the page which is write tracked which can

	 * not be fixed by page fault handler.

	 */

	if (kvm_page_track_is_active(vcpu, fault->gfn, KVM_PAGE_TRACK_WRITE))

	if (kvm_slot_page_track_is_active(fault->slot, fault->gfn, KVM_PAGE_TRACK_WRITE))

		return true;



	return false;

arch/x86/kvm/mmu/page_track.c

+13 −7
Original line number Diff line number Diff line
@@ -136,19 +136,14 @@ void kvm_slot_page_track_remove_page(struct kvm *kvm, 
}

EXPORT_SYMBOL_GPL(kvm_slot_page_track_remove_page);



/*

 * check if the corresponding access on the specified guest page is tracked.

 */

bool kvm_page_track_is_active(struct kvm_vcpu *vcpu, gfn_t gfn,

bool kvm_slot_page_track_is_active(struct kvm_memory_slot *slot, gfn_t gfn,

				   enum kvm_page_track_mode mode)

{

	struct kvm_memory_slot *slot;

	int index;



	if (WARN_ON(!page_track_mode_is_valid(mode)))

		return false;



	slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);

	if (!slot)

		return false;
@@ -156,6 +151,17 @@ bool kvm_page_track_is_active(struct kvm_vcpu *vcpu, gfn_t gfn, 
	return !!READ_ONCE(slot->arch.gfn_track[mode][index]);

}



/*

 * check if the corresponding access on the specified guest page is tracked.

 */

bool kvm_page_track_is_active(struct kvm_vcpu *vcpu, gfn_t gfn,

			      enum kvm_page_track_mode mode)

{

	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);



	return kvm_slot_page_track_is_active(slot, gfn, mode);

}



void kvm_page_track_cleanup(struct kvm *kvm)

{

	struct kvm_page_track_notifier_head *head;