Re: [PATCH v2 5/5] KVM: refactor asynchronous vcpu ioctl dispatch

[Christian Borntraeger <borntraeger@de.ibm.com>]

Am 05.08.2015 um 18:33 schrieb Radim Krčmář:
> I find the switch easier to read and modify.

yes.

> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
> ---
>  v2: new
> 
>  virt/kvm/kvm_main.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
> index d7ffe6090520..71598554deed 100644
> --- a/virt/kvm/kvm_main.c
> +++ b/virt/kvm/kvm_main.c
> @@ -2252,12 +2252,15 @@ static long kvm_vcpu_ioctl(struct file *filp,
>  	 * Special cases: vcpu ioctls that are asynchronous to vcpu execution,
>  	 * so vcpu_load() would break it.
>  	 */
> +	switch (ioctl) {
>  #if defined(CONFIG_S390) || defined(CONFIG_PPC) || defined(CONFIG_MIPS)
> -	if (ioctl == KVM_S390_INTERRUPT || ioctl == KVM_S390_IRQ || ioctl == KVM_INTERRUPT)
> -		return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
> +	case KVM_S390_INTERRUPT:
> +	case KVM_S390_IRQ:
> +	case KVM_INTERRUPT:

When you are it you might want to put the KVM_S390* withing CONFIG_S390 and
KVM_INTERRUPT within CONFIG_PPC || CONFIG_MIPS

This might speed up the switch statement for s390/ppc/mips a tiny bit. It will add
another ifdef, though. Paolo?



>  #endif
> -	if (ioctl == KVM_USER_EXIT)
> +	case KVM_USER_EXIT:
>  		return kvm_arch_vcpu_ioctl(filp, ioctl, arg);
> +	}
> 
>  	r = vcpu_load(vcpu);
>  	if (r)
>