[patch 2/4] KVM: x86: wake up waitqueue before calling get_cpu()

[mtosatti@redhat.com]

[-- Attachment #1: vcpu-kick-rt --]
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From: Jan Blunck <jblunck@suse.de>
 
This moves the get_cpu() call down to be called after we wake up the
waiters. Therefore the waitqueue locks can savely be rt mutex.
 
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Sven-Thorsten Dietrich <sven@thebigcorporation.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

Index: kvm/arch/x86/kvm/x86.c
===================================================================
--- kvm.orig/arch/x86/kvm/x86.c
+++ kvm/arch/x86/kvm/x86.c
@@ -4544,7 +4544,7 @@ static void vcpu_kick_intr(void *info)
 void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
 {
 	int ipi_pcpu = vcpu->cpu;
-	int cpu = get_cpu();
+	int cpu;
 
 	if (waitqueue_active(&vcpu->wq)) {
 		wake_up_interruptible(&vcpu->wq);
@@ -4554,6 +4554,7 @@ void kvm_vcpu_kick(struct kvm_vcpu *vcpu
 	 * We may be called synchronously with irqs disabled in guest mode,
 	 * So need not to call smp_call_function_single() in that case.
 	 */
+	cpu = get_cpu();
 	if (vcpu->guest_mode && vcpu->cpu != cpu)
 		smp_call_function_single(ipi_pcpu, vcpu_kick_intr, vcpu, 0);
 	put_cpu();