From 90cac1f52ad1db73b6ed99143ce7ad473bd90a95 Mon Sep 17 00:00:00 2001
From: Christoffer Dall <cdall@linaro.org>
Date: Tue, 21 Mar 2017 21:16:12 +0100
Subject: [PATCH] KVM: arm/arm64: vgic: Only set underflow when actually out of
LRs
We currently assume that all the interrupts in our AP list will be
queued to LRs, but that's not necessarily the case, because some of them
could have been migrated away to different VCPUs and only the VCPU
thread itself can remove interrupts from its AP list.
Therefore, slightly change the logic to only setting the underflow
interrupt when we actually run out of LRs.
As it turns out, this allows us to further simplify the handling in
vgic_sync_hwstate in later patches.
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
---
virt/kvm/arm/vgic/vgic.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c
index 104329139f24b..442f7df2a46a1 100644
--- a/virt/kvm/arm/vgic/vgic.c
+++ b/virt/kvm/arm/vgic/vgic.c
@@ -601,10 +601,8 @@ static void vgic_flush_lr_state(struct kvm_vcpu *vcpu)
DEBUG_SPINLOCK_BUG_ON(!spin_is_locked(&vgic_cpu->ap_list_lock));
- if (compute_ap_list_depth(vcpu) > kvm_vgic_global_state.nr_lr) {
- vgic_set_underflow(vcpu);
+ if (compute_ap_list_depth(vcpu) > kvm_vgic_global_state.nr_lr)
vgic_sort_ap_list(vcpu);
- }
list_for_each_entry(irq, &vgic_cpu->ap_list_head, ap_list) {
spin_lock(&irq->irq_lock);
@@ -623,8 +621,12 @@ static void vgic_flush_lr_state(struct kvm_vcpu *vcpu)
next:
spin_unlock(&irq->irq_lock);
- if (count == kvm_vgic_global_state.nr_lr)
+ if (count == kvm_vgic_global_state.nr_lr) {
+ if (!list_is_last(&irq->ap_list,
+ &vgic_cpu->ap_list_head))
+ vgic_set_underflow(vcpu);
break;
+ }
}
vcpu->arch.vgic_cpu.used_lrs = count;
--
GitLab