[PATCH V2] ARM: KVM: Allow host virt timer irq to be different from guest timer virt irq

Anup Patel anup.patel at linaro.org
Tue Apr 30 01:27:31 EDT 2013


On 29 April 2013 22:05, Christoffer Dall <cdall at cs.columbia.edu> wrote:
> On Mon, Apr 29, 2013 at 12:25 AM, Anup Patel <anup.patel at linaro.org> wrote:
>> The arch_timer irq numbers (or PPI numbers) are implementation dependent
>> so, the host virtual timer irq number can be different from guest virtual
>> timer irq number.
>
> nit: move comma before 'so'

Ok.

>
>>
>> This patch ensures that host virtual timer irq number is read from DTB and
>> guest virtual timer irq is determined based on vcpu target type.
>>
>> Signed-off-by: Anup Patel <anup.patel at linaro.org>
>> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar at linaro.org>
>> ---
>>  arch/arm/include/asm/kvm_arch_timer.h |    4 ++++
>>  arch/arm/kvm/arch_timer.c             |   27 ++++++++++++++++++++-------
>>  arch/arm/kvm/reset.c                  |   11 +++++++++++
>>  3 files changed, 35 insertions(+), 7 deletions(-)
>>
>> diff --git a/arch/arm/include/asm/kvm_arch_timer.h b/arch/arm/include/asm/kvm_arch_timer.h
>> index 68cb9e1..eeb2a3f 100644
>> --- a/arch/arm/include/asm/kvm_arch_timer.h
>> +++ b/arch/arm/include/asm/kvm_arch_timer.h
>> @@ -61,6 +61,8 @@ struct arch_timer_cpu {
>>  #ifdef CONFIG_KVM_ARM_TIMER
>>  int kvm_timer_hyp_init(void);
>>  int kvm_timer_init(struct kvm *kvm);
>> +void kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
>> +                         const struct kvm_irq_level *irq);
>>  void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu);
>>  void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu);
>>  void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu);
>> @@ -76,6 +78,8 @@ static inline int kvm_timer_init(struct kvm *kvm)
>>         return 0;
>>  }
>>
>> +static inline void kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
>> +                                       const struct kvm_irq_level *irq) {}
>>  static inline void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu) {}
>>  static inline void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu) {}
>>  static inline void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu) {}
>> diff --git a/arch/arm/kvm/arch_timer.c b/arch/arm/kvm/arch_timer.c
>> index 49a7516..c64b597 100644
>> --- a/arch/arm/kvm/arch_timer.c
>> +++ b/arch/arm/kvm/arch_timer.c
>> @@ -30,7 +30,7 @@
>>
>>  static struct timecounter *timecounter;
>>  static struct workqueue_struct *wqueue;
>> -static struct kvm_irq_level timer_irq = {
>> +static struct kvm_irq_level host_timer_irq = {
>>         .level  = 1,
>>  };
>
> there is no need for this to be a struct kvm_irq_level anymore, this
> has nothing to do with a VM, it is just a number, so an unsigned int
> would be more appropriate.

Oke, will make it unsigned int.

>
>>
>> @@ -67,8 +67,8 @@ static void kvm_timer_inject_irq(struct kvm_vcpu *vcpu)
>>
>>         timer->cntv_ctl |= ARCH_TIMER_CTRL_IT_MASK;
>>         kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id,
>> -                           vcpu->arch.timer_cpu.irq->irq,
>> -                           vcpu->arch.timer_cpu.irq->level);
>> +                           timer->irq->irq,
>> +                           timer->irq->level);
>>  }
>>
>>  static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id)
>> @@ -156,6 +156,20 @@ void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu)
>>         timer_arm(timer, ns);
>>  }
>>
>> +void kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
>> +                         const struct kvm_irq_level *irq)
>> +{
>> +       struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
>> +
>> +       /*
>> +        * The vcpu timer irq number cannot be determined in
>> +        * kvm_timer_vcpu_init() because it is called much before
>> +        * kvm_vcpu_set_target(). To handle this, we determine
>> +        * vcpu timer irq number when the vcpu is resetted.
>
> s/resetted/reset/

Ok.

>
>> +        */
>> +       timer->irq = irq;
>> +}
>> +
>>  void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
>>  {
>>         struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
>> @@ -163,12 +177,11 @@ void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
>>         INIT_WORK(&timer->expired, kvm_timer_inject_irq_work);
>>         hrtimer_init(&timer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
>>         timer->timer.function = kvm_timer_expire;
>> -       timer->irq = &timer_irq;
>>  }
>>
>>  static void kvm_timer_init_interrupt(void *info)
>>  {
>> -       enable_percpu_irq(timer_irq.irq, 0);
>> +       enable_percpu_irq(host_timer_irq.irq, 0);
>>  }
>>
>>
>> @@ -182,7 +195,7 @@ static int kvm_timer_cpu_notify(struct notifier_block *self,
>>                 break;
>>         case CPU_DYING:
>>         case CPU_DYING_FROZEN:
>> -               disable_percpu_irq(timer_irq.irq);
>> +               disable_percpu_irq(host_timer_irq.irq);
>>                 break;
>>         }
>>
>> @@ -230,7 +243,7 @@ int kvm_timer_hyp_init(void)
>>                 goto out;
>>         }
>>
>> -       timer_irq.irq = ppi;
>> +       host_timer_irq.irq = ppi;
>>
>>         err = register_cpu_notifier(&kvm_timer_cpu_nb);
>>         if (err) {
>> diff --git a/arch/arm/kvm/reset.c b/arch/arm/kvm/reset.c
>> index b80256b..0b49ad7 100644
>> --- a/arch/arm/kvm/reset.c
>> +++ b/arch/arm/kvm/reset.c
>> @@ -26,6 +26,7 @@
>>  #include <asm/cputype.h>
>>  #include <asm/kvm_arm.h>
>>  #include <asm/kvm_coproc.h>
>> +#include <asm/kvm_arch_timer.h>
>>
>>  /******************************************************************************
>>   * Cortex-A15 Reset Values
>> @@ -37,6 +38,11 @@ static struct kvm_regs a15_regs_reset = {
>>         .usr_regs.ARM_cpsr = SVC_MODE | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT,
>>  };
>>
>> +static const struct kvm_irq_level a15_vtimer_irq = {
>> +       .irq = 27,
>> +       .level = 1,
>> +};
>> +
>>
>>  /*******************************************************************************
>>   * Exported reset function
>> @@ -52,6 +58,7 @@ static struct kvm_regs a15_regs_reset = {
>>  int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
>>  {
>>         struct kvm_regs *cpu_reset;
>> +       const struct kvm_irq_level *cpu_vtimer_irq;
>>
>>         switch (vcpu->arch.target) {
>>         case KVM_ARM_TARGET_CORTEX_A15:
>> @@ -59,6 +66,7 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
>>                         return -EINVAL;
>>                 cpu_reset = &a15_regs_reset;
>>                 vcpu->arch.midr = read_cpuid_id();
>> +               cpu_vtimer_irq = &a15_vtimer_irq;
>>                 break;
>>         default:
>>                 return -ENODEV;
>> @@ -70,5 +78,8 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
>>         /* Reset CP15 registers */
>>         kvm_reset_coprocs(vcpu);
>>
>> +       /* Reset arch_timer context */
>> +       kvm_timer_vcpu_reset(vcpu, cpu_vtimer_irq);
>> +
>>         return 0;
>>  }
>> --
>> 1.7.9.5
>>
>> _______________________________________________
>> kvmarm mailing list
>> kvmarm at lists.cs.columbia.edu
>> https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm

Regards,
Anup



More information about the linux-arm-kernel mailing list