From 76dfafd536730ef9b9d99b1cf596916d52be76d1 Mon Sep 17 00:00:00 2001
From: Paolo Bonzini <pbonzini@redhat.com>
Date: Mon, 19 Dec 2016 17:17:11 +0100
Subject: KVM: x86: do not scan IRR twice on APICv vmentry
Calls to apic_find_highest_irr are scanning IRR twice, once
in vmx_sync_pir_from_irr and once in apic_search_irr. Change
sync_pir_from_irr to get the new maximum IRR from kvm_apic_update_irr;
now that it does the computation, it can also do the RVI write.
In order to avoid complications in svm.c, make the callback optional.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
arch/x86/kvm/lapic.c | 8 +++++---
arch/x86/kvm/svm.c | 6 ------
arch/x86/kvm/vmx.c | 31 +++++++++++++++++++------------
arch/x86/kvm/x86.c | 9 +++------
4 files changed, 27 insertions(+), 27 deletions(-)
(limited to 'arch/x86/kvm')
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 8af6db9b64aa..7ed2400b2777 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -515,6 +515,7 @@ int kvm_lapic_find_highest_irr(struct kvm_vcpu *vcpu)
*/
return apic_find_highest_irr(vcpu->arch.apic);
}
+EXPORT_SYMBOL_GPL(kvm_lapic_find_highest_irr);
static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
int vector, int level, int trig_mode,
@@ -580,9 +581,10 @@ static void pv_eoi_clr_pending(struct kvm_vcpu *vcpu)
static int apic_has_interrupt_for_ppr(struct kvm_lapic *apic, u32 ppr)
{
int highest_irr;
- if (apic->vcpu->arch.apicv_active)
- kvm_x86_ops->sync_pir_to_irr(apic->vcpu);
- highest_irr = apic_find_highest_irr(apic);
+ if (kvm_x86_ops->sync_pir_to_irr && apic->vcpu->arch.apicv_active)
+ highest_irr = kvm_x86_ops->sync_pir_to_irr(apic->vcpu);
+ else
+ highest_irr = apic_find_highest_irr(apic);
if (highest_irr == -1 || (highest_irr & 0xF0) <= ppr)
return -1;
return highest_irr;
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index d0414f054bdf..13cd06220b19 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -4359,11 +4359,6 @@ static void svm_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
return;
}
-static void svm_sync_pir_to_irr(struct kvm_vcpu *vcpu)
-{
- return;
-}
-
static void svm_deliver_avic_intr(struct kvm_vcpu *vcpu, int vec)
{
kvm_lapic_set_irr(vec, vcpu->arch.apic);
@@ -5373,7 +5368,6 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
.get_enable_apicv = svm_get_enable_apicv,
.refresh_apicv_exec_ctrl = svm_refresh_apicv_exec_ctrl,
.load_eoi_exitmap = svm_load_eoi_exitmap,
- .sync_pir_to_irr = svm_sync_pir_to_irr,
.hwapic_irr_update = svm_hwapic_irr_update,
.hwapic_isr_update = svm_hwapic_isr_update,
.apicv_post_state_restore = avic_post_state_restore,
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 4ac9b484e244..d03cb62b70d2 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6649,8 +6649,10 @@ static __init int hardware_setup(void)
if (!cpu_has_vmx_ple())
ple_gap = 0;
- if (!cpu_has_vmx_apicv())
+ if (!cpu_has_vmx_apicv()) {
enable_apicv = 0;
+ kvm_x86_ops->sync_pir_to_irr = NULL;
+ }
if (cpu_has_vmx_tsc_scaling()) {
kvm_has_tsc_control = true;
@@ -8722,20 +8724,25 @@ static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
}
}
-static void vmx_sync_pir_to_irr(struct kvm_vcpu *vcpu)
+static int vmx_sync_pir_to_irr(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);
+ int max_irr;
- if (!pi_test_on(&vmx->pi_desc))
- return;
-
- pi_clear_on(&vmx->pi_desc);
- /*
- * IOMMU can write to PIR.ON, so the barrier matters even on UP.
- * But on x86 this is just a compiler barrier anyway.
- */
- smp_mb__after_atomic();
- kvm_apic_update_irr(vcpu, vmx->pi_desc.pir);
+ WARN_ON(!vcpu->arch.apicv_active);
+ if (pi_test_on(&vmx->pi_desc)) {
+ pi_clear_on(&vmx->pi_desc);
+ /*
+ * IOMMU can write to PIR.ON, so the barrier matters even on UP.
+ * But on x86 this is just a compiler barrier anyway.
+ */
+ smp_mb__after_atomic();
+ max_irr = kvm_apic_update_irr(vcpu, vmx->pi_desc.pir);
+ } else {
+ max_irr = kvm_lapic_find_highest_irr(vcpu);
+ }
+ vmx_hwapic_irr_update(vcpu, max_irr);
+ return max_irr;
}
static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 8f80da161e80..75b0f30d75ee 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2909,7 +2909,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
static int kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu *vcpu,
struct kvm_lapic_state *s)
{
- if (vcpu->arch.apicv_active)
+ if (kvm_x86_ops->sync_pir_to_irr && vcpu->arch.apicv_active)
kvm_x86_ops->sync_pir_to_irr(vcpu);
return kvm_apic_get_state(vcpu, s);
@@ -6659,7 +6659,7 @@ static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu)
if (irqchip_split(vcpu->kvm))
kvm_scan_ioapic_routes(vcpu, vcpu->arch.ioapic_handled_vectors);
else {
- if (vcpu->arch.apicv_active)
+ if (kvm_x86_ops->sync_pir_to_irr && vcpu->arch.apicv_active)
kvm_x86_ops->sync_pir_to_irr(vcpu);
kvm_ioapic_scan_entry(vcpu, vcpu->arch.ioapic_handled_vectors);
}
@@ -6822,11 +6822,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
* Update architecture specific hints for APIC
* virtual interrupt delivery.
*/
- if (vcpu->arch.apicv_active) {
+ if (kvm_x86_ops->sync_pir_to_irr && vcpu->arch.apicv_active)
kvm_x86_ops->sync_pir_to_irr(vcpu);
- kvm_x86_ops->hwapic_irr_update(vcpu,
- kvm_lapic_find_highest_irr(vcpu));
- }
}
if (kvm_check_request(KVM_REQ_EVENT, vcpu) || req_int_win) {
--
cgit