[PATCH] KVM: x86: small optimization for is_mtrr_mask calculation

[linmiaohe]

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
-- 
2.19.1