diff options
| -rw-r--r-- | arch/arm/include/asm/kvm_host.h | 3 | ||||
| -rw-r--r-- | arch/arm/kvm/arm.c | 10 | ||||
| -rw-r--r-- | arch/arm64/include/asm/kvm_host.h | 3 | ||||
| -rw-r--r-- | include/kvm/arm_arch_timer.h | 2 | ||||
| -rw-r--r-- | virt/kvm/arm/arch_timer.c | 94 |
5 files changed, 72 insertions, 40 deletions
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index 84da97901f1f..c4072d9f32c7 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -234,7 +234,4 @@ static inline void kvm_arm_setup_debug(struct kvm_vcpu *vcpu) {} static inline void kvm_arm_clear_debug(struct kvm_vcpu *vcpu) {} static inline void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu) {} -static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {} -static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {} - #endif /* __ARM_KVM_HOST_H__ */ diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 78b286994577..7ed4d475d83a 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -271,6 +271,16 @@ int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) return kvm_timer_should_fire(vcpu); } +void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) +{ + kvm_timer_schedule(vcpu); +} + +void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) +{ + kvm_timer_unschedule(vcpu); +} + int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) { /* Force users to call KVM_ARM_VCPU_INIT */ diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index e4f4d65f7d2b..ed039688c221 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -255,7 +255,4 @@ void kvm_arm_setup_debug(struct kvm_vcpu *vcpu); void kvm_arm_clear_debug(struct kvm_vcpu *vcpu); void kvm_arm_reset_debug_ptr(struct kvm_vcpu *vcpu); -static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {} -static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {} - #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h index e1e4d7c38dda..ef14cc1f1f26 100644 --- a/include/kvm/arm_arch_timer.h +++ b/include/kvm/arm_arch_timer.h @@ -71,5 +71,7 @@ u64 kvm_arm_timer_get_reg(struct kvm_vcpu *, u64 regid); int kvm_arm_timer_set_reg(struct kvm_vcpu *, u64 regid, u64 value); bool kvm_timer_should_fire(struct kvm_vcpu *vcpu); +void kvm_timer_schedule(struct kvm_vcpu *vcpu); +void kvm_timer_unschedule(struct kvm_vcpu *vcpu); #endif diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c index b9d3a32cbc04..32095fbb5d7c 100644 --- a/virt/kvm/arm/arch_timer.c +++ b/virt/kvm/arm/arch_timer.c @@ -111,14 +111,21 @@ static enum hrtimer_restart kvm_timer_expire(struct hrtimer *hrt) return HRTIMER_NORESTART; } +static bool kvm_timer_irq_can_fire(struct kvm_vcpu *vcpu) +{ + struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; + + return !(timer->cntv_ctl & ARCH_TIMER_CTRL_IT_MASK) && + (timer->cntv_ctl & ARCH_TIMER_CTRL_ENABLE) && + !kvm_vgic_get_phys_irq_active(timer->map); +} + bool kvm_timer_should_fire(struct kvm_vcpu *vcpu) { struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; cycle_t cval, now; - if ((timer->cntv_ctl & ARCH_TIMER_CTRL_IT_MASK) || - !(timer->cntv_ctl & ARCH_TIMER_CTRL_ENABLE) || - kvm_vgic_get_phys_irq_active(timer->map)) + if (!kvm_timer_irq_can_fire(vcpu)) return false; cval = timer->cntv_cval; @@ -127,12 +134,57 @@ bool kvm_timer_should_fire(struct kvm_vcpu *vcpu) return cval <= now; } +/* + * Schedule the background timer before calling kvm_vcpu_block, so that this + * thread is removed from its waitqueue and made runnable when there's a timer + * interrupt to handle. + */ +void kvm_timer_schedule(struct kvm_vcpu *vcpu) +{ + struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; + u64 ns; + cycle_t cval, now; + + BUG_ON(timer_is_armed(timer)); + + /* + * No need to schedule a background timer if the guest timer has + * already expired, because kvm_vcpu_block will return before putting + * the thread to sleep. + */ + if (kvm_timer_should_fire(vcpu)) + return; + + /* + * If the timer is not capable of raising interrupts (disabled or + * masked), then there's no more work for us to do. + */ + if (!kvm_timer_irq_can_fire(vcpu)) + return; + + /* The timer has not yet expired, schedule a background timer */ + cval = timer->cntv_cval; + now = kvm_phys_timer_read() - vcpu->kvm->arch.timer.cntvoff; + + ns = cyclecounter_cyc2ns(timecounter->cc, + cval - now, + timecounter->mask, + &timecounter->frac); + timer_arm(timer, ns); +} + +void kvm_timer_unschedule(struct kvm_vcpu *vcpu) +{ + struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; + timer_disarm(timer); +} + /** * kvm_timer_flush_hwstate - prepare to move the virt timer to the cpu * @vcpu: The vcpu pointer * - * Disarm any pending soft timers, since the world-switch code will write the - * virtual timer state back to the physical CPU. + * Check if the virtual timer has expired while we were running in the host, + * and inject an interrupt if that was the case. */ void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu) { @@ -140,17 +192,6 @@ void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu) bool phys_active; int ret; - /* - * We're about to run this vcpu again, so there is no need to - * keep the background timer running, as we're about to - * populate the CPU timer again. - */ - timer_disarm(timer); - - /* - * If the timer expired while we were not scheduled, now is the time - * to inject it. - */ if (kvm_timer_should_fire(vcpu)) kvm_timer_inject_irq(vcpu); @@ -176,32 +217,17 @@ void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu) * kvm_timer_sync_hwstate - sync timer state from cpu * @vcpu: The vcpu pointer * - * Check if the virtual timer was armed and either schedule a corresponding - * soft timer or inject directly if already expired. + * Check if the virtual timer has expired while we were running in the guest, + * and inject an interrupt if that was the case. */ void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu) { struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; - cycle_t cval, now; - u64 ns; BUG_ON(timer_is_armed(timer)); - if (kvm_timer_should_fire(vcpu)) { - /* - * Timer has already expired while we were not - * looking. Inject the interrupt and carry on. - */ + if (kvm_timer_should_fire(vcpu)) kvm_timer_inject_irq(vcpu); - return; - } - - cval = timer->cntv_cval; - now = kvm_phys_timer_read() - vcpu->kvm->arch.timer.cntvoff; - - ns = cyclecounter_cyc2ns(timecounter->cc, cval - now, timecounter->mask, - &timecounter->frac); - timer_arm(timer, ns); } int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu, |