[Qemu-devel] Re: [PATCH 17/22] kvm: Move irqchip event processing out of inner loop

[Avi Kivity <avi@redhat.com>]

On 01/27/2011 03:10 PM, Jan Kiszka wrote:
> Align with qemu-kvm and prepare for IO exit fix: There is no need to run
> kvm_arch_process_irqchip_events in the inner VCPU loop. Any state change
> this service processes will first cause an exit from kvm_cpu_exec
> anyway. And we will have to reenter the kernel on IO exits
> unconditionally, something that the current logic prevents.
>
> Signed-off-by: Jan Kiszka<jan.kiszka@siemens.com>
> ---
>   kvm-all.c |   11 ++++++-----
>   1 files changed, 6 insertions(+), 5 deletions(-)
>
> diff --git a/kvm-all.c b/kvm-all.c
> index 5bfa8c0..46ecc1c 100644
> --- a/kvm-all.c
> +++ b/kvm-all.c
> @@ -892,6 +892,12 @@ int kvm_cpu_exec(CPUState *env)
>
>       DPRINTF("kvm_cpu_exec()\n");
>
> +    if (kvm_arch_process_irqchip_events(env)) {
> +        env->exit_request = 0;
> +        env->exception_index = EXCP_HLT;
> +        return 0;
> +    }
> +
>       do {
>   #ifndef CONFIG_IOTHREAD
>           if (env->exit_request) {
> @@ -901,11 +907,6 @@ int kvm_cpu_exec(CPUState *env)
>           }

We check for ->exit_request here

>   #endif
>
> -        if (kvm_arch_process_irqchip_events(env)) {
> -            ret = 0;
> -            break;
> -        }
> -

But this checks for ->interrupt_request.  What ensures that we exit when 
->interrupt_request is set?

>           if (env->kvm_vcpu_dirty) {
>               kvm_arch_put_registers(env, KVM_PUT_RUNTIME_STATE);
>               env->kvm_vcpu_dirty = 0;


-- 
error compiling committee.c: too many arguments to function