[PATCH] KVM: x86/mmu: move reused pages to the top of active_mmu_pages

[Hamza Mahfooz]

Move reused shadow pages to the head of active_mmu_pages in
__kvm_mmu_get_shadow_page(). This will allow us to move towards more of
a LRU approximation eviction strategy instead of just straight FIFO.

Signed-off-by: Hamza Mahfooz <someguy@xxxxxxxxxxxxxxxxxxx>
---
 arch/x86/kvm/mmu/mmu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 02c450686b4a..2fe04e01863d 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -2395,7 +2395,8 @@ static struct kvm_mmu_page *__kvm_mmu_get_shadow_page(struct kvm *kvm,
 	if (!sp) {
 		created = true;
 		sp = kvm_mmu_alloc_shadow_page(kvm, caches, gfn, sp_list, role);
-	}
+	} else if (!list_is_head(&sp->link, &kvm->arch.active_mmu_pages))
+		list_move(&sp->link, &kvm->arch.active_mmu_pages);
 
 	trace_kvm_mmu_get_page(sp, created);
 	return sp;
-- 
2.52.0