Re: [Qemu-devel] [PATCH v2 2/8] s390x/css: IO instr handler ending control

[Halil Pasic <pasic@linux.vnet.ibm.com>]

On 10/10/2017 01:39 PM, Cornelia Huck wrote:
> On Tue, 10 Oct 2017 12:28:35 +0200
> Thomas Huth <thuth@redhat.com> wrote:
> 
>> On 09.10.2017 17:00, Halil Pasic wrote:
>>>
>>>
>>> On 10/09/2017 01:07 PM, Thomas Huth wrote:  
> 
>>>> Then, in the follow up patches, you do something like this:
>>>>
>>>>    return (IOInstEnding){.cc = 0};
>>>>
>>>> ... and that just looks very, very ugly in my eyes. The more I look at  
>>>
>>> Interesting, I found this quite expressive.  
>>
>> C'mon, we're writing C code, not Java ;-)
> 
> Every time I read that construct, I die a little bit inside...
> 
>> Well, you already gave a description in your comment in the  struct
>> IOInstEnding, so maybe something similar? Or maybe this could even be
>> merged with the definitions for the SIGP status codes:
>>
>> #define SIGP_CC_ORDER_CODE_ACCEPTED 0
>> #define SIGP_CC_STATUS_STORED       1
>> #define SIGP_CC_BUSY                2
>> #define SIGP_CC_NOT_OPERATIONAL     3
> 
> I'd rather not reuse the definitions for a different instruction, even
> if they are similar in semantics.
> 
>>> Sorry, I may be a bit to persistent on this one: I don't think it's
>>> a huge difference, but I don't feel great about changing something to
>>> what I think is (slightly) worse without being first convinced that
>>> I was wrong.  
>>
>> In the end, the code has to be accepted by the maintainers, so let's
>> leave the decision up to them whether they like this typedef struct
>> IOInstEnding or not...
> 
> Here's a strong 'do not like' from me... using an enum or define is
> fine with me.
> 

Got the message. Could we first reach an agreement on the rest of the
series? As I've said, I might need to go back to indicating exceptions
too (depending on how do we like #3), and that would mean a changed
situation. If the price for getting this in is sacrificing my strongly
type checked condition code type I can live with that.

Halil
t