[Qemu-devel] Re: [PATCH 10/21] always qemu_cpu_kick after unhalting a cpu

[Jan Kiszka <jan.kiszka@siemens.com>]

On 2011-02-21 09:43, Paolo Bonzini wrote:
> This ensures env->halt_cond is broadcast, and the loop in
> qemu_tcg_wait_io_event and qemu_kvm_wait_io_event is exited
> naturally rather than through a timeout.
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
>  hw/apic.c          |    1 +
>  hw/ppc.c           |    2 ++
>  hw/sun4m.c         |   10 ++++++++--
>  hw/sun4u.c         |    4 ++--
>  target-s390x/kvm.c |    1 +
>  5 files changed, 14 insertions(+), 4 deletions(-)
> 
> diff --git a/hw/apic.c b/hw/apic.c
> index 218d1bb..09fc61b 100644
> --- a/hw/apic.c
> +++ b/hw/apic.c
> @@ -544,6 +544,7 @@ void apic_sipi(DeviceState *d)
>          return;
>      cpu_x86_load_seg_cache_sipi(s->cpu_env, s->sipi_vector);
>      s->wait_for_sipi = 0;
> +    qemu_cpu_kick(s->cpu_env);

Meanwhile I realized that this call is also unneeded. apic_sipi is
invoked only synchronously over the respective VCPU. So please remove.

>  }
>  
>  static void apic_deliver(DeviceState *d, uint8_t dest, uint8_t dest_mode,
> diff --git a/hw/ppc.c b/hw/ppc.c
> index 968aec1..de02d33 100644
> --- a/hw/ppc.c
> +++ b/hw/ppc.c
> @@ -208,6 +208,7 @@ static void ppc970_set_irq (void *opaque, int pin, int level)
>              } else {
>                  LOG_IRQ("%s: restart the CPU\n", __func__);
>                  env->halted = 0;
> +                qemu_cpu_kick(env);
>              }
>              break;
>          case PPC970_INPUT_HRESET:
> @@ -300,6 +301,7 @@ static void ppc40x_set_irq (void *opaque, int pin, int level)
>              } else {
>                  LOG_IRQ("%s: restart the CPU\n", __func__);
>                  env->halted = 0;
> +                qemu_cpu_kick(env);
>              }
>              break;
>          case PPC40x_INPUT_DEBUG:
> diff --git a/hw/sun4m.c b/hw/sun4m.c
> index 30e8a21..df3aa32 100644
> --- a/hw/sun4m.c
> +++ b/hw/sun4m.c
> @@ -253,15 +253,21 @@ void cpu_check_irqs(CPUState *env)
>      }
>  }
>  
> +static void cpu_kick_irq(CPUState *env)
> +{
> +    env->halted = 0;
> +    cpu_check_irqs(env);
> +    qemu_cpu_kick(env);
> +}
> +
>  static void cpu_set_irq(void *opaque, int irq, int level)
>  {
>      CPUState *env = opaque;
>  
>      if (level) {
>          trace_sun4m_cpu_set_irq_raise(irq);
> -        env->halted = 0;
>          env->pil_in |= 1 << irq;
> -        cpu_check_irqs(env);
> +        cpu_kick_irq(env);
>      } else {
>          trace_sun4m_cpu_set_irq_lower(irq);
>          env->pil_in &= ~(1 << irq);
> diff --git a/hw/sun4u.c b/hw/sun4u.c
> index 90b1ce2..d282324 100644
> --- a/hw/sun4u.c
> +++ b/hw/sun4u.c
> @@ -298,6 +298,7 @@ static void cpu_kick_irq(CPUState *env)
>  {
>      env->halted = 0;
>      cpu_check_irqs(env);
> +    qemu_cpu_kick(env);
>  }
>  
>  static void cpu_set_irq(void *opaque, int irq, int level)
> @@ -306,9 +307,8 @@ static void cpu_set_irq(void *opaque, int irq, int level)
>  
>      if (level) {
>          CPUIRQ_DPRINTF("Raise CPU IRQ %d\n", irq);
> -        env->halted = 0;
>          env->pil_in |= 1 << irq;
> -        cpu_check_irqs(env);
> +        cpu_kick_irq(env);
>      } else {
>          CPUIRQ_DPRINTF("Lower CPU IRQ %d\n", irq);
>          env->pil_in &= ~(1 << irq);
> diff --git a/target-s390x/kvm.c b/target-s390x/kvm.c
> index b349812..6e94274 100644
> --- a/target-s390x/kvm.c
> +++ b/target-s390x/kvm.c
> @@ -194,6 +194,7 @@ static void kvm_s390_interrupt_internal(CPUState *env, int type, uint32_t parm,
>  
>      env->halted = 0;
>      env->exception_index = -1;
> +    qemu_cpu_kick(env);
>  
>      kvmint.type = type;
>      kvmint.parm = parm;

Otherwise, it looks good.

Jan

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