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| author | Joerg Roedel <joerg.roedel@amd.com> | 2010-07-01 16:00:11 +0200 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2010-08-01 10:47:30 +0300 |
| commit | 828554136bbacae6e39fc31b9cd7e7c660ad7530 (patch) | |
| tree | 4e2ec85ff33c9c1e7245e83ed8e4fa3791007ef7 /virt/kvm/kvm_main.c | |
| parent | 95c87e2b4460a488ec7ce42f273893e410ab385a (diff) | |
| download | linux-828554136bbacae6e39fc31b9cd7e7c660ad7530.tar.bz2 | |
KVM: Remove unnecessary divide operations
This patch converts unnecessary divide and modulo operations
in the KVM large page related code into logical operations.
This allows to convert gfn_t to u64 while not breaking 32
bit builds.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'virt/kvm/kvm_main.c')
| -rw-r--r-- | virt/kvm/kvm_main.c | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index ec2e3c6ac7ed..a60b6b053b6f 100644 --- 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; /* |