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Diffstat (limited to 'arch/x86/kvm/lapic.c')
-rw-r--r--arch/x86/kvm/lapic.c45
1 files changed, 38 insertions, 7 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index fbb0e6df121b..3cd227ff807f 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -70,6 +70,11 @@
#define APIC_BROADCAST 0xFF
#define X2APIC_BROADCAST 0xFFFFFFFFul
+static bool lapic_timer_advance_adjust_done = false;
+#define LAPIC_TIMER_ADVANCE_ADJUST_DONE 100
+/* step-by-step approximation to mitigate fluctuation */
+#define LAPIC_TIMER_ADVANCE_ADJUST_STEP 8
+
static inline int apic_test_vector(int vec, void *bitmap)
{
return test_bit(VEC_POS(vec), (bitmap) + REG_POS(vec));
@@ -955,14 +960,14 @@ bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src,
map = rcu_dereference(kvm->arch.apic_map);
ret = kvm_apic_map_get_dest_lapic(kvm, &src, irq, map, &dst, &bitmap);
- if (ret)
+ if (ret) {
+ *r = 0;
for_each_set_bit(i, &bitmap, 16) {
if (!dst[i])
continue;
- if (*r < 0)
- *r = 0;
*r += kvm_apic_set_irq(dst[i]->vcpu, irq, dest_map);
}
+ }
rcu_read_unlock();
return ret;
@@ -1472,7 +1477,7 @@ static bool lapic_timer_int_injected(struct kvm_vcpu *vcpu)
void wait_lapic_expire(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
- u64 guest_tsc, tsc_deadline;
+ u64 guest_tsc, tsc_deadline, ns;
if (!lapic_in_kernel(vcpu))
return;
@@ -1492,6 +1497,24 @@ void wait_lapic_expire(struct kvm_vcpu *vcpu)
if (guest_tsc < tsc_deadline)
__delay(min(tsc_deadline - guest_tsc,
nsec_to_cycles(vcpu, lapic_timer_advance_ns)));
+
+ if (!lapic_timer_advance_adjust_done) {
+ /* too early */
+ if (guest_tsc < tsc_deadline) {
+ ns = (tsc_deadline - guest_tsc) * 1000000ULL;
+ do_div(ns, vcpu->arch.virtual_tsc_khz);
+ lapic_timer_advance_ns -= min((unsigned int)ns,
+ lapic_timer_advance_ns / LAPIC_TIMER_ADVANCE_ADJUST_STEP);
+ } else {
+ /* too late */
+ ns = (guest_tsc - tsc_deadline) * 1000000ULL;
+ do_div(ns, vcpu->arch.virtual_tsc_khz);
+ lapic_timer_advance_ns += min((unsigned int)ns,
+ lapic_timer_advance_ns / LAPIC_TIMER_ADVANCE_ADJUST_STEP);
+ }
+ if (abs(guest_tsc - tsc_deadline) < LAPIC_TIMER_ADVANCE_ADJUST_DONE)
+ lapic_timer_advance_adjust_done = true;
+ }
}
static void start_sw_tscdeadline(struct kvm_lapic *apic)
@@ -2621,17 +2644,25 @@ int kvm_hv_vapic_msr_read(struct kvm_vcpu *vcpu, u32 reg, u64 *data)
return 0;
}
-int kvm_lapic_enable_pv_eoi(struct kvm_vcpu *vcpu, u64 data)
+int kvm_lapic_enable_pv_eoi(struct kvm_vcpu *vcpu, u64 data, unsigned long len)
{
u64 addr = data & ~KVM_MSR_ENABLED;
+ struct gfn_to_hva_cache *ghc = &vcpu->arch.pv_eoi.data;
+ unsigned long new_len;
+
if (!IS_ALIGNED(addr, 4))
return 1;
vcpu->arch.pv_eoi.msr_val = data;
if (!pv_eoi_enabled(vcpu))
return 0;
- return kvm_gfn_to_hva_cache_init(vcpu->kvm, &vcpu->arch.pv_eoi.data,
- addr, sizeof(u8));
+
+ if (addr == ghc->gpa && len <= ghc->len)
+ new_len = ghc->len;
+ else
+ new_len = len;
+
+ return kvm_gfn_to_hva_cache_init(vcpu->kvm, ghc, addr, new_len);
}
void kvm_apic_accept_events(struct kvm_vcpu *vcpu)