[Qemu-devel] Re: [PATCH 03/15] kvm: Install optimized interrupt handlers

[Marcelo Tosatti <mtosatti@redhat.com>]

On Fri, Mar 04, 2011 at 11:20:00AM +0100, Jan Kiszka wrote:
> KVM only requires to set the raised IRQ in CPUState and, if the user
> space irqchip is used, to kick the receiving vcpu if it is remote.
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
>  kvm-all.c |   17 +++++++++++++++++
>  1 files changed, 17 insertions(+), 0 deletions(-)
> 
> diff --git a/kvm-all.c b/kvm-all.c
> index 226843c..c460d45 100644
> --- a/kvm-all.c
> +++ b/kvm-all.c
> @@ -650,6 +650,20 @@ static CPUPhysMemoryClient kvm_cpu_phys_memory_client = {
>      .log_stop = kvm_log_stop,
>  };
>  
> +static void kvm_handle_interrupt(CPUState *env, int mask)
> +{
> +    env->interrupt_request |= mask;
> +

If the env->interrupt_request request is processed in userspace, such as
MCE, the kick is still necessary for irqchip case. CPU_INTERRUPT_DEBUG
is another example, no?

> +    if (!qemu_cpu_self(env)) {
> +        qemu_cpu_kick(env);
> +    }
> +}
> +
> +static void kvm_handle_interrupt_kernel_irqchip(CPUState *env, int mask)
> +{
> +    env->interrupt_request |= mask;
> +}
> +