[RFC v2 03/10] KVM: arm/arm64: Decouple kvm timer functions from virtual timer

Jintack Lim jintack at cs.columbia.edu
Mon Jan 30 09:17:53 PST 2017


On Sun, Jan 29, 2017 at 7:01 AM, Marc Zyngier <marc.zyngier at arm.com> wrote:
> On Fri, Jan 27 2017 at 01:04:53 AM, Jintack Lim <jintack at cs.columbia.edu> wrote:
>> Now that we have a separate structure for timer context, make functions
>> general so that they can work with any timer context, not just the
>
>   generic?

yes, thanks!

>
>> virtual timer context.  This does not change the virtual timer
>> functionality.
>>
>> Signed-off-by: Jintack Lim <jintack at cs.columbia.edu>
>> ---
>>  arch/arm/kvm/arm.c           |  2 +-
>>  include/kvm/arm_arch_timer.h |  3 ++-
>>  virt/kvm/arm/arch_timer.c    | 55 ++++++++++++++++++++++----------------------
>>  3 files changed, 30 insertions(+), 30 deletions(-)
>>
>> diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
>> index 9d74464..9a34a3c 100644
>> --- a/arch/arm/kvm/arm.c
>> +++ b/arch/arm/kvm/arm.c
>> @@ -301,7 +301,7 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
>>
>>  int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
>>  {
>> -     return kvm_timer_should_fire(vcpu);
>> +     return kvm_timer_should_fire(vcpu, vcpu_vtimer(vcpu));
>>  }
>>
>>  void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu)
>> diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h
>> index 1b9c988..d921d20 100644
>> --- a/include/kvm/arm_arch_timer.h
>> +++ b/include/kvm/arm_arch_timer.h
>> @@ -67,7 +67,8 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
>>  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);
>> +bool kvm_timer_should_fire(struct kvm_vcpu *vcpu,
>> +                        struct arch_timer_context *timer_ctx);
>>  void kvm_timer_schedule(struct kvm_vcpu *vcpu);
>>  void kvm_timer_unschedule(struct kvm_vcpu *vcpu);
>>
>> diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c
>> index fa4c042..f72005a 100644
>> --- a/virt/kvm/arm/arch_timer.c
>> +++ b/virt/kvm/arm/arch_timer.c
>> @@ -98,13 +98,13 @@ static void kvm_timer_inject_irq_work(struct work_struct *work)
>>       kvm_vcpu_kick(vcpu);
>>  }
>>
>> -static u64 kvm_timer_compute_delta(struct kvm_vcpu *vcpu)
>> +static u64 kvm_timer_compute_delta(struct kvm_vcpu *vcpu,
>> +                                struct arch_timer_context *timer_ctx)
>>  {
>>       u64 cval, now;
>> -     struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
>>
>> -     cval = vtimer->cnt_cval;
>> -     now = kvm_phys_timer_read() - vtimer->cntvoff;
>> +     cval = timer_ctx->cnt_cval;
>> +     now = kvm_phys_timer_read() - timer_ctx->cntvoff;
>>
>>       if (now < cval) {
>>               u64 ns;
>> @@ -133,7 +133,7 @@ static enum hrtimer_restart kvm_timer_expire(struct hrtimer *hrt)
>>        * PoV (NTP on the host may have forced it to expire
>>        * early). If we should have slept longer, restart it.
>>        */
>> -     ns = kvm_timer_compute_delta(vcpu);
>> +     ns = kvm_timer_compute_delta(vcpu, vcpu_vtimer(vcpu));
>>       if (unlikely(ns)) {
>>               hrtimer_forward_now(hrt, ns_to_ktime(ns));
>>               return HRTIMER_RESTART;
>> @@ -143,42 +143,40 @@ static enum hrtimer_restart kvm_timer_expire(struct hrtimer *hrt)
>>       return HRTIMER_NORESTART;
>>  }
>>
>> -static bool kvm_timer_irq_can_fire(struct kvm_vcpu *vcpu)
>> +static bool kvm_timer_irq_can_fire(struct arch_timer_context *timer_ctx)
>>  {
>> -     struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
>> -
>> -     return !(vtimer->cnt_ctl & ARCH_TIMER_CTRL_IT_MASK) &&
>> -             (vtimer->cnt_ctl & ARCH_TIMER_CTRL_ENABLE);
>> +     return !(timer_ctx->cnt_ctl & ARCH_TIMER_CTRL_IT_MASK) &&
>> +             (timer_ctx->cnt_ctl & ARCH_TIMER_CTRL_ENABLE);
>>  }
>>
>> -bool kvm_timer_should_fire(struct kvm_vcpu *vcpu)
>> +bool kvm_timer_should_fire(struct kvm_vcpu *vcpu,
>> +                        struct arch_timer_context *timer_ctx)
>>  {
>> -     struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
>>       u64 cval, now;
>>
>> -     if (!kvm_timer_irq_can_fire(vcpu))
>> +     if (!kvm_timer_irq_can_fire(timer_ctx))
>>               return false;
>>
>> -     cval = vtimer->cnt_cval;
>> -     now = kvm_phys_timer_read() - vtimer->cntvoff;
>> +     cval = timer_ctx->cnt_cval;
>> +     now = kvm_phys_timer_read() - timer_ctx->cntvoff;
>>
>>       return cval <= now;
>>  }
>>
>> -static void kvm_timer_update_irq(struct kvm_vcpu *vcpu, bool new_level)
>> +static void kvm_timer_update_mapped_irq(struct kvm_vcpu *vcpu, bool new_level,
>> +                                     struct arch_timer_context *timer_ctx)
>>  {
>>       int ret;
>> -     struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
>>
>>       BUG_ON(!vgic_initialized(vcpu->kvm));
>>
>> -     vtimer->active_cleared_last = false;
>> -     vtimer->irq.level = new_level;
>> -     trace_kvm_timer_update_irq(vcpu->vcpu_id, vtimer->irq.irq,
>> -                                vtimer->irq.level);
>> +     timer_ctx->active_cleared_last = false;
>> +     timer_ctx->irq.level = new_level;
>> +     trace_kvm_timer_update_irq(vcpu->vcpu_id, timer_ctx->irq.irq,
>> +                                timer_ctx->irq.level);
>>       ret = kvm_vgic_inject_mapped_irq(vcpu->kvm, vcpu->vcpu_id,
>> -                                      vtimer->irq.irq,
>> -                                      vtimer->irq.level);
>> +                                      timer_ctx->irq.irq,
>> +                                      timer_ctx->irq.level);
>>       WARN_ON(ret);
>>  }
>>
>> @@ -200,8 +198,8 @@ static int kvm_timer_update_state(struct kvm_vcpu *vcpu)
>>       if (!vgic_initialized(vcpu->kvm) || !timer->enabled)
>>               return -ENODEV;
>>
>> -     if (kvm_timer_should_fire(vcpu) != vtimer->irq.level)
>> -             kvm_timer_update_irq(vcpu, !vtimer->irq.level);
>> +     if (kvm_timer_should_fire(vcpu, vtimer) != vtimer->irq.level)
>> +             kvm_timer_update_mapped_irq(vcpu, !vtimer->irq.level, vtimer);
>>
>>       return 0;
>>  }
>> @@ -214,6 +212,7 @@ static int kvm_timer_update_state(struct kvm_vcpu *vcpu)
>>  void kvm_timer_schedule(struct kvm_vcpu *vcpu)
>>  {
>>       struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
>> +     struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
>>
>>       BUG_ON(timer_is_armed(timer));
>>
>> @@ -222,18 +221,18 @@ void kvm_timer_schedule(struct kvm_vcpu *vcpu)
>>        * already expired, because kvm_vcpu_block will return before putting
>>        * the thread to sleep.
>>        */
>> -     if (kvm_timer_should_fire(vcpu))
>> +     if (kvm_timer_should_fire(vcpu, vtimer))
>>               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))
>> +     if (!kvm_timer_irq_can_fire(vtimer))
>>               return;
>>
>>       /*  The timer has not yet expired, schedule a background timer */
>> -     timer_arm(timer, kvm_timer_compute_delta(vcpu));
>> +     timer_arm(timer, kvm_timer_compute_delta(vcpu, vtimer));
>>  }
>>
>>  void kvm_timer_unschedule(struct kvm_vcpu *vcpu)
>
> Acked-by: Marc Zyngier <marc.zyngier at arm.com>
>
>           M.
> --
> Jazz is not dead. It just smells funny.
>




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