linux-kernel - [PATCH 03/10] KVM: x86: Drop local pvclock_flags variable in kvm_guest_time

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Message-ID: <20250118005552.2626804-4-seanjc@google.com>
Date: Fri, 17 Jan 2025 16:55:45 -0800
From: Sean Christopherson <seanjc@...gle.com>
To: Sean Christopherson <seanjc@...gle.com>, Paolo Bonzini <pbonzini@...hat.com>, 
	David Woodhouse <dwmw2@...radead.org>, Paul Durrant <paul@....org>
Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org, 
	syzbot+352e553a86e0d75f5120@...kaller.appspotmail.com, 
	Paul Durrant <pdurrant@...zon.com>, David Woodhouse <dwmw@...zon.co.uk>, 
	Vitaly Kuznetsov <vkuznets@...hat.com>
Subject: [PATCH 03/10] KVM: x86: Drop local pvclock_flags variable in kvm_guest_time_update()

Drop the local pvclock_flags in kvm_guest_time_update(), the local variable
is immediately shoved into the per-vCPU "cache", i.e. the local variable
serves no purpose.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/x86.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ef21158ec6b2..d8ee37dd2b57 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3178,7 +3178,6 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
 	struct kvm_arch *ka = &v->kvm->arch;
 	s64 kernel_ns;
 	u64 tsc_timestamp, host_tsc;
-	u8 pvclock_flags;
 	bool use_master_clock;
 #ifdef CONFIG_KVM_XEN
 	/*
@@ -3261,11 +3260,9 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
 	vcpu->last_guest_tsc = tsc_timestamp;
 
 	/* If the host uses TSC clocksource, then it is stable */
-	pvclock_flags = 0;
+	vcpu->hv_clock.flags = 0;
 	if (use_master_clock)
-		pvclock_flags |= PVCLOCK_TSC_STABLE_BIT;
-
-	vcpu->hv_clock.flags = pvclock_flags;
+		vcpu->hv_clock.flags |= PVCLOCK_TSC_STABLE_BIT;
 
 	if (vcpu->pv_time.active)
 		kvm_setup_guest_pvclock(v, &vcpu->pv_time, 0, false);
-- 
2.48.0.rc2.279.g1de40edade-goog