Re: [Qemu-devel] [PATCH v1 for-2.11 09/10] s390x/kvm: move KVM declarations and stubs to separate files

[David Hildenbrand]

On 17.08.2017 14:35, Thomas Huth wrote:
> On 17.08.2017 13:40, Philippe Mathieu-Daudé wrote:
>> Hi David,
>>
>> On 08/17/2017 06:22 AM, David Hildenbrand wrote:
>>> Let's do it just like the other architectures. Introduce kvm-stub.c
>>> for stubs and kvm_s390x.h for the declarations.
>>>
>>> Add a fake declaration of struct kvm_s390_irq so we don't need other
>>> ugly CONFIG_KVM checks.
>>
>> You can use an opaque pointer to avoid that ("bridge" design pattern).
>>
>> It involves few more changes but looks safer.
> 
> There is maybe even a simpler solution than that, see below ...
> 
> [...]
>>>   feat-src = $(SRC_PATH)/target/$(TARGET_BASE_ARCH)/
>>> diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
>>> index 74d5b35..aeb730c 100644
>>> --- a/target/s390x/cpu.h
>>> +++ b/target/s390x/cpu.h
>>> @@ -41,6 +41,7 @@
>>>   #include "exec/cpu-all.h"
>>>     #include "fpu/softfloat.h"
>>> +#include "kvm_s390x.h"
> 
> Do we still need that? cpu.h should theoretically be independent from
> kvm now, shouldn't it? And for the .c files, it's likely better to
> include kvm_s390x.h directly there if they require it.

It should work if:

a) we include "sysemu/kvm.h" in hw/s390x/s390-virtio-ccw.c
b) we include "target/s390x/kvm_s390x.h" in hw/intc/s390_flic_kvm.c
c) we include "kvm_s390x.h" in "internal.h"
d) we drop the "KVMState" parameter from kvm_s390_get_memslot_count()
(separate patch)

> 
> May I suggest to simply use this instead:
> 
> struct kvm_s390_irq;

That also seems to compile just fine.

> 
> No need to switch for a typedef here, you can simply use this anonymous
> struct declaration, I think.
> 
>  Thomas
> 


-- 

Thanks,

David