Re: [PATCH 2/2] Arm32: tidy the memset() macro

[Jan Beulich <jbeulich@xxxxxxxx>]

On 19.08.2022 10:24, Julien Grall wrote:
> On 19/08/2022 09:11, Jan Beulich wrote:
>> On 19.08.2022 10:06, Julien Grall wrote:
>>> On 19/08/2022 09:02, Jan Beulich wrote:
>>>> On 19.08.2022 09:58, Julien Grall wrote:
>>>>> On 19/08/2022 08:50, Jan Beulich wrote:
>>>>>> - add parentheses where they were missing (MISRA)
>>>>>> - make sure to evaluate also v exactly once (MISRA)
>>>>>> - remove excess parentheses
>>>>>> - rename local variables to not have leading underscores
>>>>>> - apply Xen coding style
>>>>>
>>>>> This code has been taken from Linux. From you write above, I don't see
>>>>> any strong reason for us to modify it (even if it is small).
>>>>
>>>> At least the MISRA issues want addressing, I suppose. Plus I wasn't
>>>> able to spot the macro in Linux anymore (nor __memzero()), so to me
>>>> there seemed to be little point to consider keeping anything "in sync"
>>>> here.
>>> I read the last part as we want a re-sync of the code (we haven't done
>>> one in the past couple of years).
>>
>> I'm afraid I'm now really confused: Which last part? I don't see how
>> any of what I have said could be read that way. Quite the opposite:
>> By stating that Linux doesn't have this macro anymore, isn't it quite
>> clear that there's nothing to re-sync against?
> Your view here if we will never re-sync the code. This is incorrect, we 
> still want to keep it close so we can benefit from improvement in the 
> Linux code. So if you start tweaking the code just for coding style 
> purpose, it will just make it more difficult for us (I appreciate this 
> is limited here).
> 
> In this case, Linux has removed __memzero() is patch ff5fdafc9e97 "ARM: 
> 8745/1: get rid of __memzero()" because the performance difference with 
> memset() was limited. For Xen, I think we should also remove the function.
> 
> With that, this patch becomes pointless.

Of course. I could have named this as an alternative in a post-commit-
message remark ... Looking forward to the re-syncing to be done then,
at which point I'll happily drop this patch.

Jan