Re: [Qemu-devel] [PATCH 2/8] s390: autodetect map private

[Alexander Graf <agraf@suse.de>]

On 06/13/2012 01:41 PM, Jan Kiszka wrote:
> On 2012-06-13 13:27, Christian Borntraeger wrote:
>> On 13/06/12 12:58, Jan Kiszka wrote:
>>>> Thinking about this a bit more, how about
>>>>
>>>> } else if (!kvm_arch_vmalloc(size,&new_block->host)) {
>>>> <normal code>
>>>> }
>>>>
>> I like that. Of course, we have to have a generic kvm_arch_vmalloc implementation
>> then.
> Then better go for kvm_vmalloc calling kvm_arch_vmalloc (in the s390 case).
>
> However, I do not like the variation of parameters and return value
> compared to normal *alloc. Better:
>
> memory = kvm_vmalloc(size);
> if (!memory)
> 	memory = qemu_vmalloc(size);
>
> But more regular (when looking at the Xen block) is guarding the call
> with kvm_enabled() and embedding qemu_vmalloc in kvm_vmalloc.

So basically

#ifdef CONFIG_TARGET_S390X
   } else if (kvm_enabled()) {
     memory = kvm_vmalloc();
   } else {
#endif

or a generic

} else if (kvm_enabled()) {
   memory = kvm_vmalloc();
} else {

? Because that one would mean we always duplicate the common 
qemu_vmalloc case. But then again, that one's only a single call, so 
maybe it's ok. Meh - I'll let you decide :).


Alex