diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c index 4604e9accc65..ef84a803433e 100644 --- a/arch/s390/kvm/interrupt.c +++ b/arch/s390/kvm/interrupt.c @@ -909,9 +909,35 @@ int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) return ckc_irq_pending(vcpu) || cpu_timer_irq_pending(vcpu); } +static u64 __calculate_sltime(struct kvm_vcpu *vcpu) +{ + u64 now, cputm, sltime = 0; + + if (ckc_interrupts_enabled(vcpu)) { + now = kvm_s390_get_tod_clock_fast(vcpu->kvm); + sltime = tod_to_ns(vcpu->arch.sie_block->ckc - now); + /* already expired or overflow? */ + if (!sltime || vcpu->arch.sie_block->ckc <= now) + return 0; + if (cpu_timer_interrupts_enabled(vcpu)) { + cputm = kvm_s390_get_cpu_timer(vcpu); + /* already expired? */ + if (cputm >> 63) + return 0; + return min(sltime, tod_to_ns(cputm)); + } + } else if (cpu_timer_interrupts_enabled(vcpu)) { + sltime = kvm_s390_get_cpu_timer(vcpu); + /* already expired? */ + if (sltime >> 63) + return 0; + } + return sltime; +} + int kvm_s390_handle_wait(struct kvm_vcpu *vcpu) { - u64 now, sltime; + u64 sltime; vcpu->stat.exit_wait_state++; @@ -924,22 +950,20 @@ int kvm_s390_handle_wait(struct kvm_vcpu *vcpu) return -EOPNOTSUPP; /* disabled wait */ } - if (!ckc_interrupts_enabled(vcpu)) { + if (!ckc_interrupts_enabled(vcpu) && + !cpu_timer_interrupts_enabled(vcpu)) { VCPU_EVENT(vcpu, 3, "%s", "enabled wait w/o timer"); __set_cpu_idle(vcpu); goto no_timer; } - now = kvm_s390_get_tod_clock_fast(vcpu->kvm); - sltime = tod_to_ns(vcpu->arch.sie_block->ckc - now); - - /* underflow */ - if (vcpu->arch.sie_block->ckc < now) + sltime = __calculate_sltime(vcpu); + if (!sltime) return 0; __set_cpu_idle(vcpu); hrtimer_start(&vcpu->arch.ckc_timer, ktime_set (0, sltime) , HRTIMER_MODE_REL); - VCPU_EVENT(vcpu, 4, "enabled wait via clock comparator: %llu ns", sltime); + VCPU_EVENT(vcpu, 4, "enabled wait: %llu ns", sltime); no_timer: srcu_read_unlock(&vcpu->kvm->srcu, vcpu->srcu_idx); kvm_vcpu_block(vcpu); @@ -966,18 +990,16 @@ void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu) enum hrtimer_restart kvm_s390_idle_wakeup(struct hrtimer *timer) { struct kvm_vcpu *vcpu; - u64 now, sltime; + u64 sltime; vcpu = container_of(timer, struct kvm_vcpu, arch.ckc_timer); - now = kvm_s390_get_tod_clock_fast(vcpu->kvm); - sltime = tod_to_ns(vcpu->arch.sie_block->ckc - now); + sltime = __calculate_sltime(vcpu); /* * If the monotonic clock runs faster than the tod clock we might be * woken up too early and have to go back to sleep to avoid deadlocks. */ - if (vcpu->arch.sie_block->ckc > now && - hrtimer_forward_now(timer, ns_to_ktime(sltime))) + if (sltime && hrtimer_forward_now(timer, ns_to_ktime(sltime))) return HRTIMER_RESTART; kvm_s390_vcpu_wakeup(vcpu); return HRTIMER_NORESTART;