KVM: introduce a table to map slot id to index in memslots array
The operation of getting dirty log is frequent when framebuffer-based
displays are used(for example, Xwindow), so, we introduce a mapping table
to speed up id_to_memslot()
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 6e8eb15..e289486 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -446,7 +446,7 @@
struct kvm_memslots *slots = kvm->memslots;
for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
- slots->memslots[i].id = i;
+ slots->id_to_index[i] = slots->memslots[i].id = i;
}
static struct kvm *kvm_create_vm(void)
@@ -674,8 +674,13 @@
*/
static void sort_memslots(struct kvm_memslots *slots)
{
+ int i;
+
sort(slots->memslots, KVM_MEM_SLOTS_NUM,
sizeof(struct kvm_memory_slot), cmp_memslot, NULL);
+
+ for (i = 0; i < KVM_MEM_SLOTS_NUM; i++)
+ slots->id_to_index[slots->memslots[i].id] = i;
}
void update_memslots(struct kvm_memslots *slots, struct kvm_memory_slot *new)