From: Joerg Roedel <joerg.roedel@amd.com>
Date: Wed, 18 Feb 2009 13:08:59 +0000 (+0100)
Subject: KVM: MMU: remove redundant check in mmu_set_spte
X-Git-Tag: v2.6.30-rc1~664^2~20
X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=commitdiff_plain;h=6bed6b9e84bf5e6b468847a50c0751389fdd01d4

KVM: MMU: remove redundant check in mmu_set_spte

The following code flow is unnecessary:

	if (largepage)
		was_rmapped = is_large_pte(*shadow_pte);
	 else
	 	was_rmapped = 1;

The is_large_pte() function will always evaluate to one here because the
(largepage && !is_large_pte) case is already handled in the first
if-clause. So we can remove this check and set was_rmapped to one always
here.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Acked-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index ef060ec..c90b4b2 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -1791,12 +1791,8 @@ static void mmu_set_spte(struct kvm_vcpu *vcpu, u64 *shadow_pte,
 			pgprintk("hfn old %lx new %lx\n",
 				 spte_to_pfn(*shadow_pte), pfn);
 			rmap_remove(vcpu->kvm, shadow_pte);
-		} else {
-			if (largepage)
-				was_rmapped = is_large_pte(*shadow_pte);
-			else
-				was_rmapped = 1;
-		}
+		} else
+			was_rmapped = 1;
 	}
 	if (set_spte(vcpu, shadow_pte, pte_access, user_fault, write_fault,
 		      dirty, largepage, global, gfn, pfn, speculative, true)) {