On 05/03/20 03:48, linmiaohe wrote: > From: Miaohe Lin <linmiaohe@xxxxxxxxxx> > > We can get is_mtrr_mask by calculating (msr - 0x200) % 2 directly. > > Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> > --- > arch/x86/kvm/mtrr.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/x86/kvm/mtrr.c b/arch/x86/kvm/mtrr.c > index 7f0059aa30e1..a98701d9f2bf 100644 > --- a/arch/x86/kvm/mtrr.c > +++ b/arch/x86/kvm/mtrr.c > @@ -348,7 +348,7 @@ static void set_var_mtrr_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data) > int index, is_mtrr_mask; > > index = (msr - 0x200) / 2; > - is_mtrr_mask = msr - 0x200 - 2 * index; > + is_mtrr_mask = (msr - 0x200) % 2; > cur = &mtrr_state->var_ranges[index]; > > /* remove the entry if it's in the list. */ > @@ -424,7 +424,7 @@ int kvm_mtrr_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata) > int is_mtrr_mask; > > index = (msr - 0x200) / 2; > - is_mtrr_mask = msr - 0x200 - 2 * index; > + is_mtrr_mask = (msr - 0x200) % 2; > if (!is_mtrr_mask) > *pdata = vcpu->arch.mtrr_state.var_ranges[index].base; > else > If you're going to do that, might as well use ">> 1" for index instead of "/ 2", and "msr & 1" for is_mtrr_mask. Paolo
