linux-kernel - [PATCH 32/33] KVM: MMU: Merge shadow level check in FNAME(fetch)

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Date:	Sun,  6 Jan 2008 16:39:38 +0200
From:	Avi Kivity <avi@...ranet.com>
To:	linux-kernel@...r.kernel.org, kvm-devel@...ts.sourceforge.net
Cc:	"Dong, Eddie" <eddie.dong@...el.com>
Subject: [PATCH 32/33] KVM: MMU: Merge shadow level check in FNAME(fetch)

From: Dong, Eddie <eddie.dong@...el.com>

Remove the redundant level check when fetching
shadow pte for present & non-present spte.

Signed-off-by: Yaozu (Eddie) Dong <eddie.dong@...el.com>
Signed-off-by: Avi Kivity <avi@...ranet.com>
---
 arch/x86/kvm/paging_tmpl.h |    7 ++-----
 1 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index 3499205..03ba860 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -300,16 +300,13 @@ static u64 *FNAME(fetch)(struct kvm_vcpu *vcpu, gva_t addr,
 		bool new_page = 0;
 
 		shadow_ent = ((u64 *)__va(shadow_addr)) + index;
+		if (level == PT_PAGE_TABLE_LEVEL)
+			break;
 		if (is_shadow_present_pte(*shadow_ent)) {
-			if (level == PT_PAGE_TABLE_LEVEL)
-				break;
 			shadow_addr = *shadow_ent & PT64_BASE_ADDR_MASK;
 			continue;
 		}
 
-		if (level == PT_PAGE_TABLE_LEVEL)
-			break;
-
 		if (level - 1 == PT_PAGE_TABLE_LEVEL
 		    && walker->level == PT_DIRECTORY_LEVEL) {
 			metaphysical = 1;
-- 
1.5.3.7

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