diff mbox

[v4,01/11] arm/arm64: KVM: Fix ordering of timer/GIC on guest entry

Message ID 1438962347-17541-2-git-send-email-marc.zyngier@arm.com
State New
Headers show

Commit Message

Marc Zyngier Aug. 7, 2015, 3:45 p.m. UTC 
As we now inject the timer interrupt when we're about to enter
the guest, it makes a lot more sense to make sure this happens
before the vgic code queues the pending interrupts.

Otherwise, we get the interrupt on the following exit, which is
not great for latency (and leads to all kind of bizarre issues
when using with active interrupts at the HW level).

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
---
 arch/arm/kvm/arm.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)
diff mbox

Patch

diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 9ce5cf0..1141d21 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -523,8 +523,8 @@  int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		if (vcpu->arch.pause)
 			vcpu_pause(vcpu);
 
-		kvm_vgic_flush_hwstate(vcpu);
 		kvm_timer_flush_hwstate(vcpu);
+		kvm_vgic_flush_hwstate(vcpu);
 
 		preempt_disable();
 		local_irq_disable();
@@ -540,8 +540,8 @@  int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		if (ret <= 0 || need_new_vmid_gen(vcpu->kvm)) {
 			local_irq_enable();
 			preempt_enable();
-			kvm_timer_sync_hwstate(vcpu);
 			kvm_vgic_sync_hwstate(vcpu);
+			kvm_timer_sync_hwstate(vcpu);
 			continue;
 		}
 
@@ -587,9 +587,8 @@  int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
 		trace_kvm_exit(kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
 		preempt_enable();
 
-
-		kvm_timer_sync_hwstate(vcpu);
 		kvm_vgic_sync_hwstate(vcpu);
+		kvm_timer_sync_hwstate(vcpu);
 
 		ret = handle_exit(vcpu, run, ret);
 	}