From 31fc4f95dddc4ebc9f9596a2720662e15e5d444e Mon Sep 17 00:00:00 2001 From: Wei Yang Date: Wed, 22 Aug 2018 21:57:11 +0800 Subject: [PATCH] KVM: leverage change to adjust slots->used_slots in update_memslots() update_memslots() is only called by __kvm_set_memory_region(), in which "change" is calculated and indicates how to adjust slots->used_slots * increase by one if it is KVM_MR_CREATE * decrease by one if it is KVM_MR_DELETE * not change for others This patch adjusts slots->used_slots in update_memslots() based on "change" value instead of re-calculate those states again. Signed-off-by: Wei Yang Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 587e1a0a8715..acc951cc2663 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -805,20 +805,25 @@ static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot) * sorted array and known changed memslot position. */ static void update_memslots(struct kvm_memslots *slots, - struct kvm_memory_slot *new) + struct kvm_memory_slot *new, + enum kvm_mr_change change) { int id = new->id; int i = slots->id_to_index[id]; struct kvm_memory_slot *mslots = slots->memslots; WARN_ON(mslots[i].id != id); - if (!new->npages) { - WARN_ON(!mslots[i].npages); - if (mslots[i].npages) - slots->used_slots--; - } else { - if (!mslots[i].npages) - slots->used_slots++; + switch (change) { + case KVM_MR_CREATE: + slots->used_slots++; + WARN_ON(mslots[i].npages || !new->npages); + break; + case KVM_MR_DELETE: + slots->used_slots--; + WARN_ON(new->npages || !mslots[i].npages); + break; + default: + break; } while (i < KVM_MEM_SLOTS_NUM - 1 && @@ -1054,7 +1059,7 @@ int __kvm_set_memory_region(struct kvm *kvm, memset(&new.arch, 0, sizeof(new.arch)); } - update_memslots(slots, &new); + update_memslots(slots, &new, change); old_memslots = install_new_memslots(kvm, as_id, slots); kvm_arch_commit_memory_region(kvm, mem, &old, &new, change);