KVM: Remove unnecessary divide operations

[lisovros/linux_canprio.git] / virt / kvm / kvm_main.c

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index ec2e3c6ac7ed9985cc7505a502c6c1c357d3fc33..a60b6b053b6fca12cb33056752d69e5fee2805fa 100644 (file)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -626,9 +626,9 @@ int __kvm_set_memory_region(struct kvm *kvm,
                if (new.lpage_info[i])
                        continue;
 
-               lpages = 1 + (base_gfn + npages - 1) /
-                            KVM_PAGES_PER_HPAGE(level);
-               lpages -= base_gfn / KVM_PAGES_PER_HPAGE(level);
+               lpages = 1 + ((base_gfn + npages - 1)
+                            >> KVM_HPAGE_GFN_SHIFT(level));
+               lpages -= base_gfn >> KVM_HPAGE_GFN_SHIFT(level);
 
                new.lpage_info[i] = vmalloc(lpages * sizeof(*new.lpage_info[i]));
 
@@ -638,9 +638,9 @@ int __kvm_set_memory_region(struct kvm *kvm,
                memset(new.lpage_info[i], 0,
                       lpages * sizeof(*new.lpage_info[i]));
 
-               if (base_gfn % KVM_PAGES_PER_HPAGE(level))
+               if (base_gfn & (KVM_PAGES_PER_HPAGE(level) - 1))
                        new.lpage_info[i][0].write_count = 1;
-               if ((base_gfn+npages) % KVM_PAGES_PER_HPAGE(level))
+               if ((base_gfn+npages) & (KVM_PAGES_PER_HPAGE(level) - 1))
                        new.lpage_info[i][lpages - 1].write_count = 1;
                ugfn = new.userspace_addr >> PAGE_SHIFT;
                /*