This patch makes sure that kvm_write_guest() is called at every guest enter. We do not, however, want to update all the structure at all times, so we add a flag that basically tells it whether or not to do the whole operation
Signed-off-by: Glauber Costa <[email protected]> --- arch/x86/kvm/x86.c | 10 ++++++++-- 1 files changed, 8 insertions(+), 2 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index e7e3b50..f4b77ea 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -895,7 +895,7 @@ static void kvm_set_time_scale(uint32_t tsc_khz, struct pvclock_vcpu_time_info * static DEFINE_PER_CPU(unsigned long, cpu_tsc_khz); -static void kvm_write_guest_time(struct kvm_vcpu *v) +static void kvm_write_guest_time(struct kvm_vcpu *v, bool update_time) { struct timespec ts; unsigned long flags; @@ -906,6 +906,9 @@ static void kvm_write_guest_time(struct kvm_vcpu *v) if ((!vcpu->time_page)) return; + if (!update_time) + return; + this_tsc_khz = get_cpu_var(cpu_tsc_khz); if (unlikely(vcpu->hv_clock_tsc_khz != this_tsc_khz)) { kvm_set_time_scale(this_tsc_khz, &vcpu->hv_clock); @@ -4671,6 +4674,7 @@ static void kvm_put_guest_xcr0(struct kvm_vcpu *vcpu) static int vcpu_enter_guest(struct kvm_vcpu *vcpu) { int r; + bool update_kvm_time = 0; bool req_int_win = !irqchip_in_kernel(vcpu->kvm) && vcpu->run->request_interrupt_window; @@ -4680,7 +4684,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) if (kvm_check_request(KVM_REQ_MIGRATE_TIMER, vcpu)) __kvm_migrate_timers(vcpu); if (kvm_check_request(KVM_REQ_KVMCLOCK_UPDATE, vcpu)) - kvm_write_guest_time(vcpu); + update_kvm_time = 1; if (kvm_check_request(KVM_REQ_MMU_SYNC, vcpu)) kvm_mmu_sync_roots(vcpu); if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu)) @@ -4701,6 +4705,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu) } } + kvm_write_guest_time(vcpu, update_kvm_time); + r = kvm_mmu_reload(vcpu); if (unlikely(r)) goto out; -- 1.6.2.2 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
