linux-kernel - [PATCH] KVM: X86: avoid meaningless kvm_apicv

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Date:   Tue, 25 Feb 2020 10:21:19 +0800
From:   linmiaohe <linmiaohe@...wei.com>
To:     <pbonzini@...hat.com>, <rkrcmar@...hat.com>,
        <sean.j.christopherson@...el.com>, <vkuznets@...hat.com>,
        <wanpengli@...cent.com>, <jmattson@...gle.com>, <joro@...tes.org>,
        <tglx@...utronix.de>, <mingo@...hat.com>, <bp@...en8.de>,
        <hpa@...or.com>
CC:     <linmiaohe@...wei.com>, <kvm@...r.kernel.org>,
        <linux-kernel@...r.kernel.org>, <x86@...nel.org>
Subject: [PATCH] KVM: X86: avoid meaningless kvm_apicv_activated() check

From: Miaohe Lin <linmiaohe@...wei.com>

After test_and_set_bit() for kvm->arch.apicv_inhibit_reasons, we will
always get false when calling kvm_apicv_activated() because it's sure
apicv_inhibit_reasons do not equal to 0.

Signed-off-by: Miaohe Lin <linmiaohe@...wei.com>
---
 arch/x86/kvm/x86.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ddcc51b89e2c..fa62dcb0ed0c 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8018,8 +8018,7 @@ void kvm_request_apicv_update(struct kvm *kvm, bool activate, ulong bit)
 		    !kvm_apicv_activated(kvm))
 			return;
 	} else {
-		if (test_and_set_bit(bit, &kvm->arch.apicv_inhibit_reasons) ||
-		    kvm_apicv_activated(kvm))
+		if (test_and_set_bit(bit, &kvm->arch.apicv_inhibit_reasons))
 			return;
 	}
 
-- 
2.19.1