[PATCH 03/19] KVM: move slots_lock acquision down to vapic_exit

[Avi Kivity]

From: Marcelo Tosatti <mtosatti@xxxxxxxxxx>

There is no need to grab slots_lock if the vapic_page will not
be touched.

Signed-off-by: Marcelo Tosatti <mtosatti@xxxxxxxxxx>
Signed-off-by: Avi Kivity <avi@xxxxxxxxxxxx>
---
 arch/x86/kvm/x86.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 0fbc032..ef53d88 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2787,8 +2787,10 @@ static void vapic_exit(struct kvm_vcpu *vcpu)
 	if (!apic || !apic->vapic_addr)
 		return;
 
+	down_read(&vcpu->kvm->slots_lock);
 	kvm_release_page_dirty(apic->vapic_page);
 	mark_page_dirty(vcpu->kvm, apic->vapic_addr >> PAGE_SHIFT);
+	up_read(&vcpu->kvm->slots_lock);
 }
 
 static int __vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
@@ -2944,9 +2946,7 @@ out:
 
 	post_kvm_run_save(vcpu, kvm_run);
 
-	down_read(&vcpu->kvm->slots_lock);
 	vapic_exit(vcpu);
-	up_read(&vcpu->kvm->slots_lock);
 
 	return r;
 }
-- 
1.5.6.1

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