commit 0061d53daf26f introduced a mechanism to execute a global clock update for a vm. We can apply this periodically in order to propagate host NTP corrections. Also, if all vcpus of a vm are pinned, then without an additional trigger, no guest NTP corrections can propagate either, as the current trigger is only vcpu cpu migration. Signed-off-by: Andrew Jones <drjones@xxxxxxxxxx> --- v2: greatly simplify things by creating per vm sync work, and not worrying about vms making simultaneous update requests. arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/x86.c | 20 ++++++++++++++++++++ 2 files changed, 21 insertions(+) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 9aa09d330a4b5..85be627ef5de2 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -599,6 +599,7 @@ struct kvm_arch { u64 master_kernel_ns; cycle_t master_cycle_now; struct delayed_work kvmclock_update_work; + struct delayed_work kvmclock_sync_work; struct kvm_xen_hvm_config xen_hvm_config; diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index e656719750fdf..17c57c1ed1835 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1660,6 +1660,20 @@ static void kvm_gen_kvmclock_update(struct kvm_vcpu *v) KVMCLOCK_UPDATE_DELAY); } +#define KVMCLOCK_SYNC_PERIOD (300 * HZ) + +static void kvmclock_sync_fn(struct work_struct *work) +{ + struct delayed_work *dwork = to_delayed_work(work); + struct kvm_arch *ka = container_of(dwork, struct kvm_arch, + kvmclock_sync_work); + struct kvm *kvm = container_of(ka, struct kvm, arch); + + schedule_delayed_work(&kvm->arch.kvmclock_update_work, 0); + schedule_delayed_work(&kvm->arch.kvmclock_sync_work, + KVMCLOCK_SYNC_PERIOD); +} + static bool msr_mtrr_valid(unsigned msr) { switch (msr) { @@ -6733,6 +6747,7 @@ int kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) { int r; struct msr_data msr; + struct kvm *kvm = vcpu->kvm; r = vcpu_load(vcpu); if (r) @@ -6743,6 +6758,9 @@ int kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) kvm_write_tsc(vcpu, &msr); vcpu_put(vcpu); + schedule_delayed_work(&kvm->arch.kvmclock_sync_work, + KVMCLOCK_SYNC_PERIOD); + return r; } @@ -7036,6 +7054,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) pvclock_update_vm_gtod_copy(kvm); INIT_DELAYED_WORK(&kvm->arch.kvmclock_update_work, kvmclock_update_fn); + INIT_DELAYED_WORK(&kvm->arch.kvmclock_sync_work, kvmclock_sync_fn); return 0; } @@ -7074,6 +7093,7 @@ static void kvm_free_vcpus(struct kvm *kvm) void kvm_arch_sync_events(struct kvm *kvm) { + cancel_delayed_work_sync(&kvm->arch.kvmclock_sync_work); cancel_delayed_work_sync(&kvm->arch.kvmclock_update_work); kvm_free_all_assigned_devices(kvm); kvm_free_pit(kvm); -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html