linux-kernel - [PATCH 08/19] KVM: SVM: Remove redundant cluster calculation that also creates a shadow

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Message-ID: <20220831003506.4117148-9-seanjc@google.com>
Date:   Wed, 31 Aug 2022 00:34:55 +0000
From:   Sean Christopherson <seanjc@...gle.com>
To:     Sean Christopherson <seanjc@...gle.com>,
        Paolo Bonzini <pbonzini@...hat.com>
Cc:     kvm@...r.kernel.org, linux-kernel@...r.kernel.org,
        Suravee Suthikulpanit <suravee.suthikulpanit@....com>,
        Maxim Levitsky <mlevitsk@...hat.com>,
        Li RongQing <lirongqing@...du.com>
Subject: [PATCH 08/19] KVM: SVM: Remove redundant cluster calculation that
 also creates a shadow

Drop the redundant "cluster" calculation and its horrific shadowing in
the x2avic logical mode path.  The "cluster" that is declared at an outer
scope is derived using the exact same calculation and has performed the
left-shift.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/svm/avic.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
index 14f567550a1e..8c9cad96008e 100644
--- a/arch/x86/kvm/svm/avic.c
+++ b/arch/x86/kvm/svm/avic.c
@@ -410,10 +410,9 @@ static int avic_kick_target_vcpus_fast(struct kvm *kvm, struct kvm_lapic *source
 			 * For x2APIC logical mode, cannot leverage the index.
 			 * Instead, calculate physical ID from logical ID in ICRH.
 			 */
-			int cluster = (icrh & 0xffff0000) >> 16;
 			int apic = ffs(bitmap) - 1;
 
-			l1_physical_id = (cluster << 4) + apic;
+			l1_physical_id = cluster + apic;
 		}
 	}
 
-- 
2.37.2.672.g94769d06f0-goog