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-rw-r--r--virt/kvm/irqchip.c8
-rw-r--r--virt/kvm/kvm_main.c113
-rw-r--r--virt/kvm/vfio.c5
3 files changed, 106 insertions, 20 deletions
diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c
index 21c14244f4c4..d7ea8e20dae4 100644
--- a/virt/kvm/irqchip.c
+++ b/virt/kvm/irqchip.c
@@ -213,11 +213,15 @@ int kvm_set_irq_routing(struct kvm *kvm,
goto out;
r = -EINVAL;
- if (ue->flags)
+ if (ue->flags) {
+ kfree(e);
goto out;
+ }
r = setup_routing_entry(new, e, ue);
- if (r)
+ if (r) {
+ kfree(e);
goto out;
+ }
++ue;
}
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 8b8a44453670..eb4c9d2849dc 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -66,9 +66,18 @@
MODULE_AUTHOR("Qumranet");
MODULE_LICENSE("GPL");
-static unsigned int halt_poll_ns;
+/* halt polling only reduces halt latency by 5-7 us, 500us is enough */
+static unsigned int halt_poll_ns = 500000;
module_param(halt_poll_ns, uint, S_IRUGO | S_IWUSR);
+/* Default doubles per-vcpu halt_poll_ns. */
+static unsigned int halt_poll_ns_grow = 2;
+module_param(halt_poll_ns_grow, int, S_IRUGO);
+
+/* Default resets per-vcpu halt_poll_ns . */
+static unsigned int halt_poll_ns_shrink;
+module_param(halt_poll_ns_shrink, int, S_IRUGO);
+
/*
* Ordering of locks:
*
@@ -217,6 +226,7 @@ int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
vcpu->kvm = kvm;
vcpu->vcpu_id = id;
vcpu->pid = NULL;
+ vcpu->halt_poll_ns = 0;
init_waitqueue_head(&vcpu->wq);
kvm_async_pf_vcpu_init(vcpu);
@@ -387,6 +397,36 @@ static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
return young;
}
+static int kvm_mmu_notifier_clear_young(struct mmu_notifier *mn,
+ struct mm_struct *mm,
+ unsigned long start,
+ unsigned long end)
+{
+ struct kvm *kvm = mmu_notifier_to_kvm(mn);
+ int young, idx;
+
+ idx = srcu_read_lock(&kvm->srcu);
+ spin_lock(&kvm->mmu_lock);
+ /*
+ * Even though we do not flush TLB, this will still adversely
+ * affect performance on pre-Haswell Intel EPT, where there is
+ * no EPT Access Bit to clear so that we have to tear down EPT
+ * tables instead. If we find this unacceptable, we can always
+ * add a parameter to kvm_age_hva so that it effectively doesn't
+ * do anything on clear_young.
+ *
+ * Also note that currently we never issue secondary TLB flushes
+ * from clear_young, leaving this job up to the regular system
+ * cadence. If we find this inaccurate, we might come up with a
+ * more sophisticated heuristic later.
+ */
+ young = kvm_age_hva(kvm, start, end);
+ spin_unlock(&kvm->mmu_lock);
+ srcu_read_unlock(&kvm->srcu, idx);
+
+ return young;
+}
+
static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
struct mm_struct *mm,
unsigned long address)
@@ -419,6 +459,7 @@ static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
.invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
.invalidate_range_end = kvm_mmu_notifier_invalidate_range_end,
.clear_flush_young = kvm_mmu_notifier_clear_flush_young,
+ .clear_young = kvm_mmu_notifier_clear_young,
.test_young = kvm_mmu_notifier_test_young,
.change_pte = kvm_mmu_notifier_change_pte,
.release = kvm_mmu_notifier_release,
@@ -1906,6 +1947,35 @@ void kvm_vcpu_mark_page_dirty(struct kvm_vcpu *vcpu, gfn_t gfn)
}
EXPORT_SYMBOL_GPL(kvm_vcpu_mark_page_dirty);
+static void grow_halt_poll_ns(struct kvm_vcpu *vcpu)
+{
+ int old, val;
+
+ old = val = vcpu->halt_poll_ns;
+ /* 10us base */
+ if (val == 0 && halt_poll_ns_grow)
+ val = 10000;
+ else
+ val *= halt_poll_ns_grow;
+
+ vcpu->halt_poll_ns = val;
+ trace_kvm_halt_poll_ns_grow(vcpu->vcpu_id, val, old);
+}
+
+static void shrink_halt_poll_ns(struct kvm_vcpu *vcpu)
+{
+ int old, val;
+
+ old = val = vcpu->halt_poll_ns;
+ if (halt_poll_ns_shrink == 0)
+ val = 0;
+ else
+ val /= halt_poll_ns_shrink;
+
+ vcpu->halt_poll_ns = val;
+ trace_kvm_halt_poll_ns_shrink(vcpu->vcpu_id, val, old);
+}
+
static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu)
{
if (kvm_arch_vcpu_runnable(vcpu)) {
@@ -1928,10 +1998,11 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu)
ktime_t start, cur;
DEFINE_WAIT(wait);
bool waited = false;
+ u64 block_ns;
start = cur = ktime_get();
- if (halt_poll_ns) {
- ktime_t stop = ktime_add_ns(ktime_get(), halt_poll_ns);
+ if (vcpu->halt_poll_ns) {
+ ktime_t stop = ktime_add_ns(ktime_get(), vcpu->halt_poll_ns);
do {
/*
@@ -1960,7 +2031,22 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu)
cur = ktime_get();
out:
- trace_kvm_vcpu_wakeup(ktime_to_ns(cur) - ktime_to_ns(start), waited);
+ block_ns = ktime_to_ns(cur) - ktime_to_ns(start);
+
+ if (halt_poll_ns) {
+ if (block_ns <= vcpu->halt_poll_ns)
+ ;
+ /* we had a long block, shrink polling */
+ else if (vcpu->halt_poll_ns && block_ns > halt_poll_ns)
+ shrink_halt_poll_ns(vcpu);
+ /* we had a short halt and our poll time is too small */
+ else if (vcpu->halt_poll_ns < halt_poll_ns &&
+ block_ns < halt_poll_ns)
+ grow_halt_poll_ns(vcpu);
+ } else
+ vcpu->halt_poll_ns = 0;
+
+ trace_kvm_vcpu_wakeup(block_ns, waited);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_block);
@@ -2206,6 +2292,11 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
}
kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu;
+
+ /*
+ * Pairs with smp_rmb() in kvm_get_vcpu. Write kvm->vcpus
+ * before kvm->online_vcpu's incremented value.
+ */
smp_wmb();
atomic_inc(&kvm->online_vcpus);
@@ -2618,9 +2709,6 @@ static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
case KVM_CAP_USER_MEMORY:
case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
-#ifdef CONFIG_KVM_APIC_ARCHITECTURE
- case KVM_CAP_SET_BOOT_CPU_ID:
-#endif
case KVM_CAP_INTERNAL_ERROR_DATA:
#ifdef CONFIG_HAVE_KVM_MSI
case KVM_CAP_SIGNAL_MSI:
@@ -2716,17 +2804,6 @@ static long kvm_vm_ioctl(struct file *filp,
r = kvm_ioeventfd(kvm, &data);
break;
}
-#ifdef CONFIG_KVM_APIC_ARCHITECTURE
- case KVM_SET_BOOT_CPU_ID:
- r = 0;
- mutex_lock(&kvm->lock);
- if (atomic_read(&kvm->online_vcpus) != 0)
- r = -EBUSY;
- else
- kvm->bsp_vcpu_id = arg;
- mutex_unlock(&kvm->lock);
- break;
-#endif
#ifdef CONFIG_HAVE_KVM_MSI
case KVM_SIGNAL_MSI: {
struct kvm_msi msi;
diff --git a/virt/kvm/vfio.c b/virt/kvm/vfio.c
index 620e37f741b8..1dd087da6f31 100644
--- a/virt/kvm/vfio.c
+++ b/virt/kvm/vfio.c
@@ -155,6 +155,8 @@ static int kvm_vfio_set_group(struct kvm_device *dev, long attr, u64 arg)
list_add_tail(&kvg->node, &kv->group_list);
kvg->vfio_group = vfio_group;
+ kvm_arch_start_assignment(dev->kvm);
+
mutex_unlock(&kv->lock);
kvm_vfio_update_coherency(dev);
@@ -190,6 +192,8 @@ static int kvm_vfio_set_group(struct kvm_device *dev, long attr, u64 arg)
break;
}
+ kvm_arch_end_assignment(dev->kvm);
+
mutex_unlock(&kv->lock);
kvm_vfio_group_put_external_user(vfio_group);
@@ -239,6 +243,7 @@ static void kvm_vfio_destroy(struct kvm_device *dev)
kvm_vfio_group_put_external_user(kvg->vfio_group);
list_del(&kvg->node);
kfree(kvg);
+ kvm_arch_end_assignment(dev->kvm);
}
kvm_vfio_update_coherency(dev);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-23 11:23:28 +0000